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Sample search results for: palapa b2r satellite

 

1

Modeling And Simulation Of Prolate Dual-Spin Satellite Dynamics In An Inclined Elliptical Orbit: Case Study Of Palapa B2R Satellite

  CERN Preprints

Summary: In response to the interest to re-use Palapa B2R satellite nearing its End of Life (EOL) time, an idea to incline the satellite orbit in order to cover a new region has emerged in the recent years. As a prolate dual-spin vehicle, Palapa B2R has to be stabilized against its internal energy dissipation effect. This work is focused on analyzing the dynamics of the reusable satellite in its inclined orbit. The study discusses in particular the stability of the prolate dual-spin satellite under the effect of perturbed field of gravitation due to the inclination of its elliptical orbit. Palapa B2R physical data was substituted into the dual-spin's equation of motion. The coefficient of zonal harmonics J2 was induced into the gravity-gradient moment term that affects the satellite attitude. The satellite's motion and attitude were then simulated in the perturbed gravitational field by J2, with the variation of orbit's eccentricity and inclination. The analysis of the satellite dynamics and its stability was conducte...

Muliadi, J; Budiyono, A
2008-01-01

2

Solutions to Home-work 11 1. (a) Notice that if B2(R3) and x, y R3 are arbitrary, and

  Mathematics Websites

Summary: define ij = (ei, ej), then (x, y) = (x, 3 j=1 ej (y)ej) = 3 j=1 ej (y)(x, ej) = 3 j=1 ej (y)( 3 i=1 ei (x)ei, ej) = 3 i=1 3 j=1 ei (x)ej (y)(ei, ej) = 3 i=1 3 j=1 (ei, ej)ei ej (x, y) , thereby showing that {ei ej : 1 i, j 3} is a spanning set for B2(R3). The above string of equations can also be used

Sunder, V S

3

Causal continuity in degenerate spacetimes A.Borde a;1 , H.F.Dowker b;2 , R.S.Garcia c;2 , R.D.Sorkin d;3 , S.Surya e;4

  Physics Websites

Summary: Causal continuity in degenerate spacetimes #3; A.Borde a;1 , H.F.Dowker b;2 , R.S.Garcia c;2 , R.D.Sorkin d;3 , S.Surya e;4 1 Institute of Cosmology, Department of Physics and Astronomy Tufts University SW7 2BZ, United Kingdom 3 Physics Department, Syracuse University, Syracuse, N.Y., 13244-1130, USA 4

Sorkin, Rafael Dolnick

4

SATELLITE METEOROLOGY Guosheng Liu

  Geosciences Websites

Summary: SATELLITE METEOROLOGY Guosheng Liu Department of Meteorology, Florida State University, Florida sensing, scattering, sounding channel, window channel. Contents 1. Introduction 2. Principles of Satellite 2.7 Ocean Surface Wind Measurements by Scatterometers 3. Applications of Satellite Observations

Wang, Yuqing

5

Correspondence Satellites: make data

  Environmental Sciences and Ecology Websites

Summary: Correspondence Satellites: make data freely accessible The cost of accessing satellite data governments do not have a free-access policy for their satellite images. One solution would be to combine data all the data free to access online. Data from NASA's MODIS and all of their Earth-observation imagery

Courchamp, Franck

6

EUROPE'S GEOSTATIONARY METEOROLOGICAL SATELLITES

  Geosciences Websites

Summary: METEOSAT EUROPE'S GEOSTATIONARY METEOROLOGICAL SATELLITES MONITORING WEATHER AND CLIMATE FROM SPACE, 6 July 2010 Paul de Valk Koninklijk nederlands Meteorologisch instituut (KnMi) "you need satellites for a country to have its own satellites so it is very beneficial to share costs in Europe, as we do through Eu

Stoffelen, Ad

7

Equalizers for communications satellites

  MIT - DSpace

Summary: This thesis investigates equalization for advanced protected satellite communications systems in development at MIT Lincoln Laboratory. Equalizers facilitate high data rate communication by correcting dispersion in the ...

Fay, Leon
2008-01-01

8

SPRING 2013 SATELLITE TUTORING CENTERS

  Biology and Medicine Websites

Summary: SPRING 2013 SATELLITE TUTORING CENTERS Satellite Tutoring Centers will not operate on the following dates: Monday, 1/21/13 Sunday, 3/3/13 -- Sunday, 3/10/13 Satellite Tutoring Center services end Tuesday

Plotkin, Joshua B.

9

Experimental Satellite Quantum Communications

  Quantum Physics (arXiv)

Summary: Quantum Communications on planetary scale require complementary channels including ground and satellite links. The former have progressed up to commercial stage using fiber-cables, while for satellite links, the absence of terminals in orbit has impaired theirs development. However, the demonstration of the feasibility of such links is crucial for designing space payloads and to eventually enable the realization of protocols such as quantum-key-distribution (QKD) and quantum teleportation along satellite-to-ground or intersatellite links. We demonstrated the faithful transmission of qubits from space to ground by exploiting satellite corner cube retroreflectors acting as transmitter in orbit, obtaining a low error rate suitable for QKD. We also propose a two-way QKD protocol exploiting modulated retroreflectors that necessitates a minimal payload on satellite, thus facilitating the expansion of Space Quantum Communications.

Giuseppe Vallone; Davide Bacco; Daniele Dequal; Simone Gaiarin; Vincenza Luceri; Giuseppe Bianco; Paolo Villoresi
2014-06-16

10

Satellite Products and Services Review Board ATBD: Satellite-Derived

  Environmental Sciences and Ecology Websites

Summary: Satellite Products and Services Review Board ATBD: Satellite-Derived Ocean Heat Content Version 1.0 July 2012 ___________________________________ #12;NOAA /RSMAS ATBD : Satellite-Derived Ocean Heat/STAR) #12;NOAA /RSMAS ATBD : Satellite-Derived Ocean Heat Content Product Page 3 of 32 TABLE OF CONTENTS

Miami, University of

11

Destriping Satellite Images

  MIT - DSpace

Summary: Before satellite images obtained with multiple image sensors can be used in image analysis, corrections must be introduced for the differences in transfer functions on these sensors. Methods are here presented for ...

Horn, B.K.P.
1978-03-01

12

Satellite Radio: Its Global Impact

  Biology and Medicine Websites

Summary: Satellite Radio: Its Global Impact TIFR Alumni Lecture By S.Rangarajan #12;1 A wonder called RADIO Broadcast Station 1950: First FM Broadcast 1999: First Satellite Radio Broadcast #12;3 Science of Radio "One (Aug 1930) #12;4 Satellite Orbits decided by Applications Types: LEO,GEO,HEO..... In a geostationary

Udgaonkar, Jayant B.

13

Dynamical friction on satellite galaxies

  Astrophysics (arXiv)

Summary: For a rigid model satellite, Chandrasekhar's dynamical friction formula describes the orbital evolution quite accurately, when the Coulomb logarithm is chosen appropriately. However, it is not known if the orbital evolution of a real satellite with the internal degree of freedom can be described by the dynamical friction formula. We performed N-body simulation of the orbital evolution of a self-consistent satellite galaxy within a self-consistent parent galaxy. We found that the orbital decay of the simulated satellite is significantly faster than the estimate from the dynamical friction formula. The main cause of this discrepancy is that the stars stripped out of the satellite are still close to the satellite, and increase the drag force on the satellite through two mechanisms. One is the direct drag force from particles in the trailing tidal arm, a non-axisymmetric force that slows the satellite down. The other is the indirect effect that is caused by the particles remaining close to the satellite after escape. The force from them enhances the wake caused in the parent galaxy by dynamical friction, and this larger wake in turn slows the satellite down more than expected from the contribution of its bound mass. We found these two have comparable effects, and the combined effect can be as large as 20% of the total drag force on the satellite.

Michiko Fujii; Yoko Funato; Junichiro Makino
2006-06-23

14

Binary Satellite Galaxies

  CERN Preprints

Summary: Suggestions have appeared in the literature that the following five pairs of Milky Way and Andromeda satellite galaxies are gravitationally bound: Draco and Ursa Minor, Leo IV and V, Andromeda I and III, NGC 147 and 185, and the Magellanic clouds. Under the assumption that a given pair is gravitationally bound, the Virial theorem provides an estimate of its total mass and so its instantaneous tidal radius. For all of these pairs except for the Magellanic clouds the resulting total mass is 2 to 4 orders of magnitude higher than that within the half light radius. Furthermore in the case of each pair except for Leo IV and Leo V, the estimated tidal radius is inferior to the separation between the two satellites. Therefore all or almost all of these systems are not gravitationally bound. We note several possible explanations for the proximities and similar radial velocities of the satellites in each pair, for example they may have condensed from the same infalling structure or they may be bound by a nongravitatio...

Evslin, Jarah
2013-01-01

15

Interferometric Observations of Geosynchronous Satellites

  CERN Preprints

Summary: In recent years, a large number of geosynchronous satellites are being planned to provide augmentation services for enhancing the precision to global positioning systems, e.g., GPS, in applications such as aircraft landing. In this paper, we present a scheme for co-locating passive satellite observational facilities with a radio astronomy facility to open a new possibility of providing valuable data for radio astronomical imaging, ionospheric studies and satellite orbit estimation.

Subrahmanya, C R; Somashekar, R
2011-01-01

16

REZA RABIEI, PhD 2444 Benny Crescent ~ Montreal, Quebec H4B 2R3

  Engineering Websites

Summary: .rabiei@mail.mcgill.ca EDUCATION PhD, Mechanical Engineering Sep. 2007 ­ May 2011 McGill University, Montreal, GPA: 4.0/4.0 University of Science and Technology, Tehran, Iran, GPA: 3.74/4.0 Dissertation: Optimum design of composite Engineering Sep. 2000 ­ Sep. 2004 Tehran Polytechnic, Tehran, Iran, GPA: 3.63/4.0 Dissertation: Mechanical

Barthelat, Francois

17

5, 98619906, 2005 Satellite surface

  Physics Websites

Summary: ACPD 5, 9861­9906, 2005 Satellite surface parameters for mesoscale modelling B. de Foy et al. Title and Physics Discussions Satellite-derived land surface parameters for mesoscale modelling of the Mexico City for mesoscale modelling B. de Foy et al. Title Page Abstract Introduction Conclusions References Tables Figures

Paris-Sud XI, Université de

18

2, 135, 2005 Satellite observations

  Physics Websites

Summary: -year satellite observations of instability waves in the Tropical Atlantic Ocean A. C. V. Caltabiano1 , I. SOSD 2, 1­35, 2005 Satellite observations of TIW in the Atlantic Ocean A. C. V. Caltabiano et al Print Version Interactive Discussion EGU Ocean Science Discussions, 2, 1­35, 2005 www.ocean

Paris-Sud XI, Université de

19

6, 79457958, 2006 Satellite monitoring

  Physics Websites

Summary: ACPD 6, 7945­7958, 2006 Satellite monitoring of vegetation by DOAS T. Wagner et al. Title Page Chemistry and Physics Discussions Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS) in the red spectral range T. Wagner, S. Beirle, M. Grzegorski, and U. Platt

Paris-Sud XI, Université de

20

Research Councils UK Satellites and

  Computer Technologies and Information Sciences Websites

Summary: Research Councils UK Satellites and commercial applications of space #12;Research funded data and energy-efficient computing; Satellites and commercial applications of space; Robotics, the UK space industry is strong and growing, with a favourable balance of commercial and public sector

Berzins, M.

21

Modelling and control of satellite formations 

  Texas A&M University - TxSpace

Summary: Formation flying is a new paradigm in space mission design, aimed at replacing large satellites with multiple small satellites. Some of the proposed benefits of formation flying satellites are: (i) Reduced mission costs and (ii) Multi mission...

Vaddi, Veera Venkata Sesha Sai
2004-09-30

22

ORIGINAL PAPER Satellite telemetry reveals individual variation

  Physics Websites

Summary: ORIGINAL PAPER Satellite telemetry reveals individual variation in juvenile Bonelli's eagle by satellite telemetry. Three distinct phases during the juveniles' first year of life were detected, namely

Paris-Sud XI, Université de

23

The tidal stripping of satellites

  Astrophysics (arXiv)

Summary: We present an improved analytic calculation for the tidal radius of satellites and test our results against N-body simulations. The tidal radius in general depends upon four factors: the potential of the host galaxy, the potential of the satellite, the orbit of the satellite and {\\it the orbit of the star within the satellite}. We demonstrate that this last point is critical and suggest using {\\it three tidal radii} to cover the range of orbits of stars within the satellite. In this way we show explicitly that prograde star orbits will be more easily stripped than radial orbits; while radial orbits are more easily stripped than retrograde ones. This result has previously been established by several authors numerically, but can now be understood analytically. For point mass, power-law (which includes the isothermal sphere), and a restricted class of split power law potentials our solution is fully analytic. For more general potentials, we provide an equation which may be rapidly solved numerically. Over short times ($\\simlt 1-2$ Gyrs $\\sim 1$ satellite orbit), we find excellent agreement between our analytic and numerical models. Over longer times, star orbits within the satellite are transformed by the tidal field of the host galaxy. In a Hubble time, this causes a convergence of the three limiting tidal radii towards the prograde stripping radius. Beyond the prograde stripping radius, the velocity dispersion will be tangentially anisotropic.

J. I. Read; M. I. Wilkinson; N. W. Evans; G. Gilmore; Jan T. Kleyna
2005-11-15

24

Redefining the Missing Satellites Problem

  Astrophysics (arXiv)

Summary: Numerical simulations of Milky-Way size Cold Dark Matter (CDM) halos predict a steeply rising mass function of small dark matter subhalos and a substructure count that greatly outnumbers the observed satellites of the Milky Way. Several proposed explanations exist, but detailed comparison between theory and observation in terms of the maximum circular velocity (Vmax) of the subhalos is hampered by the fact that Vmax for satellite halos is poorly constrained. We present comprehensive mass models for the well-known Milky Way dwarf satellites, and derive likelihood functions to show that their masses within 0.6 kpc (M_0.6) are strongly constrained by the present data. We show that the M_0.6 mass function of luminous satellite halos is flat between ~ 10^7 and 10^8 M_\\odot. We use the ``Via Lactea'' N-body simulation to show that the M_0.6 mass function of CDM subhalos is steeply rising over this range. We rule out the hypothesis that the 11 well-known satellites of the Milky Way are hosted by the 11 most massive subhalos. We show that models where the brightest satellites correspond to the earliest forming subhalos or the most massive accreted objects both reproduce the observed mass function. A similar analysis with the newly-discovered dwarf satellites will further test these scenarios and provide powerful constraints on the CDM small-scale power spectrum and warm dark matter models.

Louis E. Strigari; James S. Bullock; Manoj Kaplinghat; Juerg Diemand; Michael Kuhlen; Piero Madau
2007-10-24

25

Biogeography based Satellite Image Classification

  CERN Preprints

Summary: Biogeography is the study of the geographical distribution of biological organisms. The mindset of the engineer is that we can learn from nature. Biogeography Based Optimization is a burgeoning nature inspired technique to find the optimal solution of the problem. Satellite image classification is an important task because it is the only way we can know about the land cover map of inaccessible areas. Though satellite images have been classified in past by using various techniques, the researchers are always finding alternative strategies for satellite image classification so that they may be prepared to select the most appropriate technique for the feature extraction task in hand. This paper is focused on classification of the satellite image of a particular land cover using the theory of Biogeography based Optimization. The original BBO algorithm does not have the inbuilt property of clustering which is required during image classification. Hence modifications have been proposed to the original algorithm and...

Panchal, V K; Kaur, Navdeep; Kundra, Harish
2009-01-01

26

Shape Alignments of Satellite Galaxies

  Astrophysics (arXiv)

Summary: We test a sample of satellites of isolated primary galaxies, extracted from the 2dF Galaxy Redshift Survey (2dFGRS), for any tendency to be aligned along (or against) the primary-to-satellite radius vector. If tidal effects induce such an alignment, it would contaminate recent measurements of galaxy halo masses which use the coherent alignment induced on background galaxies by gravitational lensing. The mean tangential ellipticity of 1819 satellites within 500 kpc projected radius is = +0.004+-0.008, so no tidal alignment is detected. This implies at 95% confidence that satellite alignment is less than a 20% contamination of the alignment signal attributed to galaxy-galaxy lensing by Smith et al. (2001) and McKay et al. (2001).

G. M. Bernstein; P. Norberg
2002-05-29

27

Satellites of Isolated Elliptical Galaxies

  Astrophysics (arXiv)

Summary: Using well-defined selection criteria applied to the LEDA galaxy catalogue we have derived a sample of elliptical galaxies that can be classified as isolated. From this we have investigated the neighbourhood of these galaxies to determine the frequency and radial distribution of faint galaxies around them and hence derive an estimate of their surrounding satellite population. The results are compared and contrasted to the satellite population around isolated spiral galaxies.

Rodney M. Smith; Vicent J. Martinez
2003-09-30

28

Modern Digital Satellite Television: How It Works

  Computer Technologies and Information Sciences Websites

Summary: Modern Digital Satellite Television: How It Works Matthew C. Valenti Lane Department of Computer #12;Outline 1 Satellite Television Standards 2 DVB-S2 Modulation 3 LDPC Coding 4 Constellation Shaping Virginia UniverLDPC Codes Nov, 1, 2011 2 / 58 #12;Satellite Television Standards Outline 1 Satellite

Valenti, Matthew C.

29

MFR PAPER 1230 Finding Fish With Satellites

  Environmental Sciences and Ecology Websites

Summary: MFR PAPER 1230 Finding Fish With Satellites ANDREW J. KEMMERER and JOHNNY A. BUTLER ABSTRACT-The LANDSA T (Land Satellite) Investigation began in April 1975 to determine if satellites can be used scanners in LANDSA T satellites to measure certain ocean features for locating fishing areas for menhaden


30

Want to Install A Satellite Dish ?

  Environmental Sciences and Ecology Websites

Summary: Want to Install A Satellite Dish ? Good News! Satellite dishes are allowed in Family & Graduate of units to allow for installation of satellite dishes are not permitted. If damage oc- curs to Family damage to satellite dish equipment. 3. Residents are expected to maintain the grounds/area surrounding

Maxwell, Bruce D.

31

A networking perspective on satellite constellations

  Engineering Websites

Summary: A networking perspective on satellite constellations Ecole d'Hiver des Télécommunications de Sophia networking perspective on satellite constellations - Lloyd Wood 2 We aim to build up a picture of satellite constellations and how we can simulate them as networks. To do that, we'll cover: · orbital geometry of satellite

Wood, Lloyd

32

Realizing Future Broadband Satellite Network Services

  Computer Technologies and Information Sciences Websites

Summary: @cis.ohio-state.edu ABSTRACT Future satellite communication systems proposed use geosynchronous (GEO) satellites, medium earth challenges before telecommunications industry in the 21st century. Satellite communication networks canRealizing Future Broadband Satellite Network Services Sastri Kota Arjan Durresi, Raj Jain Lockheed

Jain, Raj

33

More Satellites of Spiral Galaxies

  Astrophysics (arXiv)

Summary: We present a revised and expanded catalog of satellite galaxies of a set of isolated spiral galaxies similar in luminosity to the Milky Way. This sample of 115 satellites, 69 of which were discovered in our multifiber redshift survey, is used to further probe the results obtained from the original sample (Zaritsky et al. 1993). The satellites are, by definition, at projected separations <~ 500 kpc, have absolute recessional velocity differences with respect to the parent spiral of less than 500 km/s and are at least 2.2 mag fainter than their associated primary galaxy. A key characteristic of this survey is the strict isolation of these systems, which simplifies any dynamical analysis. We find no evidence for a decrease in the velocity dispersion of the satellite system as a function of radius out to galactocentric radii of 400 kpc, suggesting that the halo extends well beyond 200 kpc. Furthermore, the new sample affirms our previous conclusions (Zaritsky et al. 1993) that (1) the velocity difference between a satellite and its primary is not strongly correlated with the rotation speed of the primary, (2) the system of satellites has a slight net rotation (34 \\pm 14 km\\s) in the same sense as the primary's disk, and (3) that the halo mass of an ~ L* spiral galaxy is in excess of 2 x 10^{12} solar masses.

Dennis Zaritsky; Rodney Smith; Carlos Frenk; Simon D. M. White
1996-11-24

34

Satellite Luminosities in Galaxy Groups

  Astrophysics (arXiv)

Summary: Halo model interpretations of the luminosity dependence of galaxy clustering assume that there is a central galaxy in every sufficiently massive halo, and that this central galaxy is very different from all the others in the halo. The halo model decomposition makes the remarkable prediction that the mean luminosity of the non-central galaxies in a halo should be almost independent of halo mass: the predicted increase is about 20% while the halo mass increases by a factor of more than 20. In contrast, the luminosity of the central object is predicted to increase approximately linearly with halo mass at low to intermediate masses, and logarithmically at high masses. We show that this weak, almost non-existent mass-dependence of the satellites is in excellent agreement with the satellite population in group catalogs constructed by two different collaborations. This is remarkable, because the halo model prediction was made without ever identifying groups and clusters. The halo model also predicts that the number of satellites in a halo is drawn from a Poisson distribution with mean which depends on halo mass. This, combined with the weak dependence of satellite luminosity on halo mass, suggests that the Scott effect, such that the luminosities of very bright galaxies are merely the statistically extreme values of a general luminosity distribution, may better apply to the most luminous satellite galaxy in a halo than to BCGs. If galaxies are identified with halo substructure at the present time, then central galaxies should be about 4 times more massive than satellite galaxies of the same luminosity, whereas the differences between the stellar M/L ratios should be smaller. Therefore, a comparison of the weak lensing signal from central and satellite galaxies should provide useful constraints. [abridged

Ramin A. Skibba; Ravi K. Sheth; Matthew C. Martino
2008-05-05

35

Gaussian Entanglement Distribution via Satellite

  Quantum Physics (arXiv)

Summary: In this work we analyse three quantum communication schemes for the generation of Gaussian entanglement between two ground stations. Communication occurs via a satellite over two independent atmospheric fading channels dominated by turbulence-induced beam wander. In our first scheme the engineering complexity remains largely on the ground transceivers, with the satellite acting simply as a reflector. Although the channel state information of the two atmospheric channels remains unknown in this scheme, the Gaussian entanglement generation between the ground stations can still be determined. On the ground, distillation and Gaussification procedures can be applied, leading to a refined Gaussian entanglement generation rate between the ground stations. We compare the rates produced by this first scheme with two competing schemes in which quantum complexity is added to the satellite, thereby illustrating the trade-off between space-based engineering complexity and the rate of ground-station entanglement generation.

Nedasadat Hosseinidehaj; Robert Malaney
2015-02-05

36

The Stromlo Missing Satellites Survey

  Astrophysics (arXiv)

Summary: The Stromlo Missing Satellites (SMS) program is a critical endeavor to investigate whether cold dark matter cosmology is flawed in its ability to describe the matter distribution on galaxy scales or proves itself once again as a powerful theory to make observational predictions. The project will deliver unprecedented results on Milky Way satellite numbers, their distribution and physical properties. It is the deepest, most extended survey for optically elusive dwarf satellite galaxies to date, covering the entire 20,000 sq deg of the Southern hemisphere. 150TB of CCD images will be analysed in six photometric bands, 0.5-1.0 mag fainter than SDSS produced by the ANU SkyMapper telescope over the next five years. (For more details see: http://msowww.anu.edu.au/~jerjen/SMS_Survey.html)

Helmut Jerjen
2008-11-06

37

The Stromlo Missing Satellites Survey

  CERN Preprints

Summary: The Stromlo Missing Satellites (SMS) program is a critical endeavor to investigate whether cold dark matter cosmology is flawed in its ability to describe the matter distribution on galaxy scales or proves itself once again as a powerful theory to make observational predictions. The project will deliver unprecedented results on Milky Way satellite numbers, their distribution and physical properties. It is the deepest, most extended survey for optically elusive dwarf satellite galaxies to date, covering the entire 20,000 sq deg of the Southern hemisphere. 150TB of CCD images will be analysed in six photometric bands, 0.5-1.0 mag fainter than SDSS produced by the ANU SkyMapper telescope over the next five years. (For more details see: http://msowww.anu.edu.au/~jerjen/SMS_Survey.html)

Jerjen, Helmut
2008-01-01

38

Gaussian Entanglement Distribution via Satellite

  CERN Preprints

Summary: In this work we analyse three quantum communication schemes for the generation of Gaussian entanglement between two ground stations. Communication occurs via a satellite over two independent atmospheric fading channels dominated by turbulence-induced beam wander. In our first scheme the engineering complexity remains largely on the ground transceivers, with the satellite acting simply as a reflector. Although the channel state information of the two atmospheric channels remains unknown in this scheme, the Gaussian entanglement generation between the ground stations can still be determined. On the ground, distillation and Gaussification procedures can be applied, leading to a refined Gaussian entanglement generation rate between the ground stations. We compare the rates produced by this first scheme with two competing schemes in which quantum complexity is added to the satellite, thereby illustrating the trade-off between space-based engineering complexity and the rate of ground-station entanglement generation...

Hosseinidehaj, Nedasadat
2014-01-01

39

Chameleon gravity and satellite geodesy

  CERN Preprints

Summary: We consider the possibility of the detection of a chameleon effect by an earth orbiting satellite such as LAGEOS, and possible constraints that might be placed on chameleon model parameters. Approximate constraints presented here result from using a simple monopole approximation for the gravitational field of the earth, along with results from the Khoury-Weltman chameleon model, solar system constraints obtained from the Cassini mission, and parameter bounds obtained from the LAGEOS satellite. It is furthermore suggested that a comparison of ground-based and space-based multipole moments of the geopotential could reveal a possible chameleon effect.

Morris, J R
2014-01-01

40

Chameleon gravity and satellite geodesy

  HEP - Theory (arXiv)

Summary: We consider the possibility of the detection of a chameleon effect by an earth orbiting satellite such as LAGEOS, and possible constraints that might be placed on chameleon model parameters. Approximate constraints presented here result from using a simple monopole approximation for the gravitational field of the earth, along with results from the Khoury-Weltman chameleon model, solar system constraints obtained from the Cassini mission, and parameter bounds obtained from the LAGEOS satellite. It is furthermore suggested that a comparison of ground-based and space-based multipole moments of the geopotential could reveal a possible chameleon effect.

J. R. Morris
2014-09-29

41

Satellite altimeter remote sensing of ice caps 

  Edinburgh, University of - Research Archive

Summary: This thesis investigates the use of satellite altimetry techniques for measuring surface elevation changes of ice caps. Two satellite altimeters, Radar Altimeter 2 (RA-2) and Geoscience Laser Altimeter System (GLAS) are ...

Rinne, Eero Juhani
2011-11-24

42

Are rotating planes of satellite galaxies ubiquitous?

  CERN Preprints

Summary: We compare the dynamics of satellite galaxies in the Sloan Digital Sky Survey to simple models in order to test the hypothesis that a large fraction of satellites co-rotate in coherent planes. We confirm the previously-reported excess of co-rotating satellite pairs located near diametric opposition with respect to the host, but show that this signal is unlikely to be due to rotating discs (or planes) of satellites. In particular, no overabundance of co-rotating satellites pairs is observed within $\\sim 20^{\\circ}-50^{\\circ}$ of direct opposition, as would be expected for planar distributions inclined relative to the line-of-sight. Instead, the excess co-rotation for satellite pairs within $\\sim 10^{\\circ}$ of opposition is consistent with random noise associated with undersampling of an underlying isotropic velocity distribution. We conclude that at most $10\\%$ of the hosts in our sample harbor co-rotating satellite planes (as traced by the luminous satellite population).

Phillips, John I; Bullock, James S; Boylan-Kolchin, Michael
2015-01-01

43

Transmission scheduling for wireless and satellite systems

  MIT - DSpace

Summary: We study queuing systems with time-varying service rates, as a natural model of satellite and wireless communication systems. Packets arrive at a satellite to be transmitted to one of the sub-regions (channels) in a service ...

Ganti, Anand, 1975-
2003-01-01

44

Figure 1. Satellite image before neural net Figure 5. Satellite image after

  Computer Technologies and Information Sciences Websites

Summary: Figure 1. Satellite image before neural net processing Figure 5. Satellite image after processing. Satellite image after processing for identification of land and water (Water is colored as jet black regions of New England. Figure 7. Satellite image after registering with the map of all the water resources

Michel, Howard E.

45

SATELLITE SURVEILLANCE OF TROPICAL AND SUBTROPICAL CYCLONES 6.1. Satellites.

  Environmental Sciences and Ecology Websites

Summary: CHAPTER 6 SATELLITE SURVEILLANCE OF TROPICAL AND SUBTROPICAL CYCLONES 6.1. Satellites. 6.1.1. Geostationary Operational Environmental Satellite (GOES). Using modern 3-axis stabilization for orbit control satellite data coverage is extensive, stretching from the central Pacific through the Americas


46

Advanced hybrid satellite andAdvanced hybrid satellite and terrestrial system architecture forterrestrial system architecture for

  Engineering Websites

Summary: Advanced hybrid satellite andAdvanced hybrid satellite and terrestrial system architecture Iapichino 1st phase of Ph.D. research on ``Ad hoc mobility in satellite-based networks for security communications: Satellite links Mobile ad-hoc mesh network Conclusions Future work Main achievements Bibliography

Gesbert, David

47

PERFORMANCE EVALUATION OF LEO SATELLITE CONSTELLATIONS WITH INTER-SATELLITE LINKS

  Computer Technologies and Information Sciences Websites

Summary: 1 PERFORMANCE EVALUATION OF LEO SATELLITE CONSTELLATIONS WITH INTER-SATELLITE LINKS UNDER SELF orbit (LEO) satellite constellations, used for the interconnection of high-speed networks, is presented for the establishment of inter-satellite links (ISLs) and the design of the terrestrial and space segments is presented

Papapetrou, Evaggelos

48

Reliable Multicast Transport by Satellite: a Hybrid Satellite/Terrestrial Solution with Erasure Codes

  Computer Technologies and Information Sciences Websites

Summary: multipoint communication service. In the context of reliable multicast communications, a new hybrid satellite/terrestrial approach is proposed. It aims at reducing the overall communication cost using satellite broadcasting onlyReliable Multicast Transport by Satellite: a Hybrid Satellite/Terrestrial Solution with Erasure

Mailhes, Corinne

49

Satellite Transport Protocol (STP): An SSCOPbased Transport Protocol for Datagram Satellite Networks

  Computer Technologies and Information Sciences Websites

Summary: challenges of data communications over satellite networks is the efficient transport of data over connections1 Satellite Transport Protocol (STP): An SSCOP­based Transport Protocol for Datagram Satellite in a datagram­based satellite data network. This protocol operates with high throughput and efficiency over

California at Berkeley, University of

50

Unicast-Multicast Bridging for CDEEP EDUSAT Satellite Network

  Computer Technologies and Information Sciences Websites

Summary: Unicast-Multicast Bridging for CDEEP EDUSAT Satellite Network Thesis submitted in partial #12;Abstract Satellite communication networks today are used for educational purposes. These networks interested in joining the educational programmes through the satellite must setup a satellite transceiver

Iyer, Sridhar

51

CIRES/NGDC Research Associate Satellite Sensor Systems Engineer

  Multidisciplinary Databases and Resources Websites

Summary: CIRES/NGDC Research Associate Satellite Sensor Systems Engineer The Cooperative Institute, Boulder, CO. This position is for a Satellite Sensor Systems Engineer within the NGDC Solar on the Geostationary Operational Environmental Satellites (GOES), Polar-orbiting Operational Environmental Satellites

Colorado at Boulder, University of

52

Optimal Energy Allocation and Admission Control for Communications Satellites

  Computer Technologies and Information Sciences Websites

Summary: 1 Optimal Energy Allocation and Admission Control for Communications Satellites Alvin Fu, Eytan control for communications satellites in earth orbit. These satellites receive requests for transmis- sion allocation problems in wireless commu- nications. Keywords-- Satellite, Communication, Resource Alloca- tion

Modiano, Eytan

53

Information Delivery Through Broadcasting in Satellite Communication Networks

  Engineering Websites

Summary: Information Delivery Through Broadcasting in Satellite Communication Networks Leandros Tassiulas­range multicasting capability of satellites and the asymmetry of satellite communications (high bandwidth downlink. We consider a data broadcasting model that is encountered in most asymmetric satellite communication

Tassiulas, Leandros

54

4, 39794004, 2007 Snow satellite images

  Physics Websites

Summary: HESSD 4, 3979­4004, 2007 Snow satellite images for calibration of snow dynamic C. Corbari et al System Sciences Snow satellite images for calibration of snow dynamic in a continuous distributed. Corbari (chiara.corbari@mail.polimi.it) 3979 #12;HESSD 4, 3979­4004, 2007 Snow satellite images

Paris-Sud XI, Université de

55

COORDINATED CONTROL OF SATELLITES: THE ATTITUDE CASE

  Engineering Websites

Summary: -controller structure for attitude synchronization of a satellite formation is presented. The design applies methodsCOORDINATED CONTROL OF SATELLITES: THE ATTITUDE CASE Thomas R. Krogstad Department of Engineering from mechanical synchronization to design a nonlinear observer and controller for satellites actuated

Gravdahl, Jan Tommy

56

Thursday, March 15, 2007 ICY SATELLITE SURFACES

  Physics Websites

Summary: Thursday, March 15, 2007 ICY SATELLITE SURFACES 1:30 p.m. Crystal Ballroom B Chairs: A. R. Hendrix L. M. Prockter 1:30 p.m. Dalton J. B. * Icy Saturnian Satellite Surface Compositions: Mapping and Modeling [#2415] The icy saturnian satellites are slowly, if grudgingly, beginning to give up the secrets

Rathbun, Julie A.

57

7, 1386113882, 2007 ACE-FTS satellite

  Physics Websites

Summary: ACPD 7, 13861­13882, 2007 ACE-FTS satellite validation in the UTLS M. I. Hegglin et al. Title Page Chemistry and Physics Discussions Validation of ACE-FTS satellite data in the upper troposphere #12;ACPD 7, 13861­13882, 2007 ACE-FTS satellite validation in the UTLS M. I. Hegglin et al. Title Page

Paris-Sud XI, Université de

58

Dynamics and Control of Electromagnetic Satellite Formations

  Engineering Websites

Summary: Dynamics and Control of Electromagnetic Satellite Formations Umair Ahsun, David W. Miller June 2007 SSL # 12-07 #12;2 #12;Dynamics and Control of Electromagnetic Satellite Formations by Umair Ahsun B page] #12;3 Dynamics and Control of Electromagnetic Satellite Formations by Umair Ahsun Abstract


59

7, 60376075, 2007 Balloon and satellite

  Physics Websites

Summary: ACPD 7, 6037­6075, 2007 Balloon and satellite H2O measurements in the tropical UTLS N. Montoux et a Creative Commons License. Atmospheric Chemistry and Physics Discussions Evaluation of balloon and satellite Balloon and satellite H2O measurements in the tropical UTLS N. Montoux et al. Title Page Abstract

Paris-Sud XI, Université de

60

Satellite Navigation Integrity Assurance: Lessons Learned

  Engineering Websites

Summary: Satellite Navigation Integrity Assurance: Lessons Learned from Hurricane Katrina ION GNSS 2008 by the FAA Satellite Navigation Program Office #12;17 September 2008 Lessons Learned from Hurricane Katrina 2 ­ Failure to adapt to model changes after 1965 · Lessons for Satellite Navigation Integrity Design ­ Need

Stanford University

61

PERFORMANCE EVALUATION OF NEMO IN SATELLITE NETWORKS

  Computer Technologies and Information Sciences Websites

Summary: Ivancic Satellite Networks and Architectures Branch NASA Glenn Research Center, Cleveland, OH 44135) satellites will contain multiple IP-enabled devices that are accessible through ground stations fromPERFORMANCE EVALUATION OF NEMO IN SATELLITE NETWORKS Abu Zafar M. Shahriar Mohammed Atiquzzaman

Atiquzzaman, Mohammed

62

Using Satellite Data for AQ Applications

  Environmental Sciences and Ecology Websites

Summary: and resources for end-users on data access and applications (http://airquality.gsfc.nasa.gov) TENTATIVE OUTLINEUsing Satellite Data for AQ Applications #12;AQ User's Guide Satellite Data for Air Quality for AQ applications NO2, SO2, CO, NMVOC (HCHO proxy), NH3, AOD (PM) Successful applications of satellite

Jacob, Daniel J.

63

A Satellite LO system B. G. Clark

  Physics Websites

Summary: system was that the satellite beacons being used for the purpose are actually very good oscillators on the satellite carrying the beacon. The analysis below ignores the dispersive e#11;ects of the ionosphere, which, looking at the satellite beacon. The beacon is radiating at frequency (angular) f : exp(if t

Groppi, Christopher

64

Opportunities and Challenges of Nano Satellites

  Plasma Physics and Fusion Websites

Summary: Opportunities and Challenges of Nano Satellites August, 2010 Rei Kawashima AXELSPACE Corporation #12;2 AXELSPACE - Who are we? Space venture company specialized in nano-satellites. Developer of nano but Experienced Engineers (who have built 2-3 nano-satellites at their universities) Collaborative research


65

Numerical Homotopy Algorithms for Satellite Trajectory Control

  Mathematics Websites

Summary: Numerical Homotopy Algorithms for Satellite Trajectory Control by Pole Placement 1 Jan Verschelde 2 is to illustrate the application of numerical homotopy algorithms to control the trajectory of a satellite. We words and phrases. numerical homotopy algorithms, pole placement, satellite trajectory control. 1

Verschelde, Jan

66

Satellite Infrared Soundings From NOAA Spacecraft

  Environmental Sciences and Ecology Websites

Summary: NOAA Tec / Satellite Infrared Soundings From NOAA Spacecraft #12;U.S. DEPARTMENT OF COMMERCE NATIONAL ENVIRONMENTAL SATELLITE SERVICE David S. Johnson, Director NOAA Technical Report NESS 65 Satellite Meteorology Methods of observation and computation Upper air data computation Instrument carriers


67

Satellite Eye for Galathea 3 -Slutrapport

  Multidisciplinary Databases and Resources Websites

Summary: Satellite Eye for Galathea 3 - Slutrapport Charlotte Bay Hasager, Peter Brøgger Sørensen, Jacob L Abstract (in English) (max. 2000 char.): The Satellite Eye for Galathea 3 project started on the 10th March Fonden kindly supported the Satellite Eye project with 3.890.551 DKK in the period from the 10th March


68

ATS 351, Spring 2010 Satellite 50 points

  Geosciences Websites

Summary: ATS 351, Spring 2010 Lab #8 Satellite ­ 50 points 1. (3 points) What is the polarization temperature measured by a satellite. What are some factors that affect the emissivity of a surface? 5. (5 visible and infrared satellite imagery? Explain. Give an advantage and a disadvantage for each. #12;7. (7

Rutledge, Steven

69

Instant Active Positioning with One LEO Satellite

  Engineering Websites

Summary: Instant Active Positioning with One LEO Satellite NADAV LEVANON Tel Aviv University, Tel Aviv in the Globalstar satellite communication system is discussed. ( )The two-way communication between a user terminal on the earth's surface and a single low earth orbit LEO satellite makes it possible to derive range and range

Levanon, Nadav

70

INTRODUCTION Satellites contain onboard equipment for sens-

  Computer Technologies and Information Sciences Websites

Summary: INTRODUCTION Satellites contain onboard equipment for sens- ing Earth and space, and communications, satellites are classified into three types: geosyn- chronous Earth orbit (GEO), medium Earth orbit (MEO), and low Earth orbit (LEO). LEO satellites have several advantages, such as low propagation delay and low

Atiquzzaman, Mohammed

71

Relations between Kauffman and Homfly satellite invariants

  Mathematics Websites

Summary: Relations between Kauffman and Homfly satellite invariants H. R. Morton and N. D. A. Ryder, to the general Kauffman and Homfly satellite invariants. 1 Introduction The result of Rudolph [5] relating. In this paper we show how Rudolph's result can be extended to general Kauffman satellite invariants. Our results

Morton, Hugh

72

Propagation Effects Handbook for Satellite Systems Design

  Energy Storage, Conversion and Utilization Websites

Summary: Propagation Effects Handbook for Satellite Systems Design Fifth Edition Section 1 Background Dr for Satellite Systems Design continues the long process of a continuing NASA commitment to provide and how they impact satellite communications system design and performance. The First Edition

Pulfrey, David L.

73

An Algorithm to Estimate Satellite Rainfall Rate

  Geosciences Websites

Summary: An Algorithm to Estimate Satellite Rainfall Rate Joan Manuel Castro Sánchez Advisor: Dr. Nazario the operational satellite rainfall algorithm of National Environmental Satellite Data and Information Services algorithm was implemented over Puerto Rico and it was found that some warm clouds were not detected

Gilbes, Fernando

74

Satellite Data in Meteorology Spring Semester, 2008

  Geosciences Websites

Summary: 1 ATMO-441 Satellite Data in Meteorology Spring Semester, 2008 Prerequisites: ATMO 324 & MATH 308: Satellite Meteorology--An Introduction. Academic Press, San Diego, CA. Homework Assignments: Reading from Transfer (~2.5 weeks) Chapter 4 Meteorological Satellite Instrumentation (~ 0.5 week) Chapter 5 Image


75

NASA Launches Next-Generation Communications Satellite

  Physics Websites

Summary: NASA Launches Next-Generation Communications Satellite Pg 3 Triumph Over Tragedy: Columbia's Last in Florida. "TDRS-K bolsters our network of satellites that provides essential communications to support Goddard View The Weekly ­ 2 NASA Launches Next-Generation Communications Satellite ­ 3 Dinosaur Footprints

Christian, Eric

76

Broadband satellite communication ... -Google Livros Descrio geral

  Computer Technologies and Information Sciences Websites

Summary: Broadband satellite communication ... - Google Livros Descrição geral > Pré-visualização Críticas satellite communication ... - Google Livros Esta é uma pré-visualização. O total de páginas apresentadasC&printsec=frontcover&hl=pt-PT&source=gbs_v2_summary_r&cad=0 (2 of 28) [12-08-2009 11:21:11] #12;Broadband satellite communication ... - Google

Monteiro, Edmundo

77

SCTP over Satellite Networks Shaojian Fu

  Computer Technologies and Information Sciences Websites

Summary: of SCTP for data communications over satellite links. We describe SCTP features that allow SCTP to betSCTP over Satellite Networks Shaojian Fu Mohammed Atiquzzaman School of Computer Science University of Oklahoma, Norman, OK 73019-6151. William Ivancic Satellite Networks & Architectures Branch NASA Glenn

Atiquzzaman, Mohammed

78

ORIGINAL ARTICLE Satellite clock bias estimation for iGPS

  Geosciences Websites

Summary: ORIGINAL ARTICLE Satellite clock bias estimation for iGPS John Pratt · Penina Axelrad · Kristine M is key to performance. An approach is presented for estimating the bias of each Iridium satellite clock using satellite-to-ground and satellite-to-satellite measurements. The satellite clock bias estimates

Larson, Kristine

79

Satellite decay in flattened dark matter haloes

  Astrophysics (arXiv)

Summary: We carry out a set of self-consistent N-body calculations to compare the decay rates of satellite dwarf galaxies orbiting a disc galaxy embedded in a dark matter halo (DMH). We consider both spherical and oblate axisymmetric DMHs of aspect ratio q_h=0.6. The satellites are given different initial orbital inclinations, orbital periods and mass. The live flattened DMHs with embedded discs and bulges are set-up using a new fast algorithm, MaGalie (Boily, Kroupa and Pe\\~{n}arrubia 2001). We find that the range of survival times of satellites within a flattened DMH becomes of the order of 100% larger than the same satellites within a spherical DMH. In the oblate DMH, satellites on polar orbits have the longest survival time, whereas satellites on coplanar prograde orbits are destroyed most rapidly. The orbital plane of a satellite tilts as a result of anisotropic dynamical friction, causing the satellite's orbit to align with the plane of symmetry of the DMH. Polar orbits are not subjected to alignment. Therefore the decay of a satellites in an axisymmetric DMH may provide a natural explanation for the observed lack of satellites within (0-30) degrees of their host galaxy's disc (Holmberg 1969; Zaritsky and Gonz\\'alez 1999). The computations furthermore indicate that the evolution of the orbital eccentricity $e$ is highly dependent of its initial value e(t=0) and the DMH's shape. We also discuss some implications of flattened DMHs for satellite debris streams.

Jorge Penarrubia; Pavel Kroupa; Christian M. Boily
2002-02-13

80

Star Formation in Satellite Galaxies

  Astrophysics (arXiv)

Summary: The study of satellite galaxies can provide information on the merging and aggregation processes which, according to the hierarchical clustering models, form the larger spiral galaxies we observe. With the aim of testing hierarchical models of galaxy formation, we have conducted an observational program which comprises H$\\alpha$ imaging for both the parent and the satellite galaxies, taken from the compilation by Zaritsky et al. (1997) that contains 115 galaxies orbiting 69 primary isolated spiral galaxies. We have observed a subsample of 37 spiral and irregular galaxies taken from the compilation mentioned above. The aim of this study is to determine star formation properties of the sample galaxies. In this work we present the preliminary results of this program that we have carried out with the 1.8-m Vatican Telescope (VATT).

Jose G. Funes SJ; Carlos M. Gutierrez; Francisco Prada; Marco Azzaro; Marcelo B. Ribeiro
2003-09-22

81

Star Formation in Satellite Galaxies

  CERN Preprints

Summary: The study of satellite galaxies can provide information on the merging and aggregation processes which, according to the hierarchical clustering models, form the larger spiral galaxies we observe. With the aim of testing hierarchical models of galaxy formation, we have conducted an observational program which comprises H$\\alpha$ imaging for both the parent and the satellite galaxies, taken from the compilation by Zaritsky et al. (1997) that contains 115 galaxies orbiting 69 primary isolated spiral galaxies. We have observed a subsample of 37 spiral and irregular galaxies taken from the compilation mentioned above. The aim of this study is to determine star formation properties of the sample galaxies. In this work we present the preliminary results of this program that we have carried out with the 1.8-m Vatican Telescope (VATT).

Funes, S J; Prada, F; Azzaro, M; Ribeiro, M B; SJ, Jose G. Funes; Gutierrez, Carlos M.; Prada, Francisco; Azzaro, Marco; Ribeiro, Marcelo B.
2003-01-01

82

Sweeping and shaking dwarf satellites

  Astrophysics (arXiv)

Summary: We present the first high-resolution N-Body/SPH simulations that follow the evolution of low surface brightness disk satellites in a primary halo containing both dark matter and a hot gas component. Tidal shocks turn the stellar disk into a spheroid with low $v/\\sigma$ and remove most of the outer dark and baryonic mass. In addition, by weakening the potential well of the dwarf, tides enhance the effect of ram pressure, and the gas is stripped down to radius three times smaller than the stellar component A very low gas/stars ratio results after several Gyr, similarly to what seen in dwarf spheroidal satellites of the Milky Way and M31.

Lucio Mayer; James Wadsley
2003-09-02

83

Picard satellite for solar astrometry

  CERN Preprints

Summary: The Picard solar satellite has been launched on June 15, 2010. This mission is dedicated to the measurement of the solar diameter with an expected accuracy of milliarcseconds of arc. The radiometer onboard is to measure the total solar irradiance. The final goal is the evaluation of the W, the logarithmic ratio of radius and luminosity. This parameter will help the climatologists to recover past values of the solar luminosity when the radius is available from ancient eclipses data.

Sigismondi, Costantino
2011-01-01

84

Asteroseismology with the WIRE satellite

  Astrophysics (arXiv)

Summary: I give a summary of results from the WIRE satellite, which has been used to observe bright stars from 1999-2000 and 2003-2006. The WIRE targets are monitored for up to five weeks with a duty cycle of 30-40%. The aim has been to characterize the flux variation of stars across the Hertzsprung-Russell diagram. I present an overview of the results for solar-like stars, delta Scuti stars, giant stars, and eclipsing binaries.

H. Bruntt
2007-02-01

85

The orbital poles of Milky Way satellite galaxies: a rotationally supported disc-of-satellites

  Astrophysics (arXiv)

Summary: Available proper motion measurements of Milky Way (MW) satellite galaxies are used to calculate their orbital poles and projected uncertainties. These are compared to a set of recent cold dark-matter (CDM) simulations, tailored specifically to solve the MW satellite problem. We show that the CDM satellite orbital poles are fully consistent with being drawn from a random distribution, while the MW satellite orbital poles indicate that the disc-of-satellites of the Milky Way is rotationally supported. Furthermore, the bootstrapping analysis of the spatial distribution of theoretical CDM satellites also shows that they are consistent with being randomly drawn. The theoretical CDM satellite population thus shows a significantly different orbital and spatial distribution than the MW satellites, most probably indicating that the majority of the latter are of tidal origin rather than being DM dominated sub-structures. A statistic is presented that can be used to test a possible correlation of satellite galaxy orbits with their spatial distribution.

Manuel Metz; Pavel Kroupa; Noam I. Libeskind
2008-02-26

86

Satellite-based quantum clock synchronization

  CERN Preprints

Summary: We propose a practical satellite-based quantum clock synchronization scheme with dispersion cancellation and by taking into account effects of gravitational frequency shift of the Earth. Two frequency entangled pulses are employed to synchronize two clocks, one at a ground station and the other at a satellite. The time discrepancy of the two clocks is introduced into the pulses by moving mirrors and is extracted by measuring the coincidence rate of the pulses in the interferometer. We find that the pulses are distorted due to effects of the gravitational frequency shift when they propagate between the Earth and the satellite. It is shown that the coincidence rate as well as precision of the time discrepancy are remarkably affected by gravitational frequency shift effects both for the low earth orbits satellite and geostationary earth orbits satellite cases. We also find that the precision of the clock synchronization are sensitive to the source parameters and the altitude of the satellite. Our proposal can be...

Wang, Jieci; Jing, Jiliang; Fan, Heng
2015-01-01

87

A Search for Satellite around Ceres

  CERN Preprints

Summary: We conducted a satellite search around the dwarf planet 1 Ceres using Hubble Space Telescope and ground-based Palomar data. No candidate objects were found orbiting Ceres in its entire stability region down to ~500km from the surface of Ceres. Assuming a satellite would have the same albedo as Ceres, which has a visual geometric albedo of 0.07-0.10, our detection limit is sensitive to satellites larger than 1-2 km in diameter.

Bieryla, A; Young, E F; McFadden, L A; Russell, C T; Stern, S A; Sykes, M V; Gladman, B
2011-01-01

88

Satellite Ecology: The Dearth of Environment Dependence

  Astrophysics (arXiv)

Summary: Using the Sloan Digital Sky Survey (SDSS) galaxy group catalogue of Yang et al. (2007), we study the average colour and average concentration of satellite galaxies as function of (i) their stellar mass, (ii) their group mass, and (iii) their group-centric radius. We find that the colours and concentrations of satellite galaxies are (almost) completely determined by their stellar mass. In particular, at fixed stellar mass, the average colours and concentrations of satellite galaxies are independent of either halo mass or halo-centric radius. We find clear evidence for mass segregation of satellite galaxies in haloes of all masses, and argue that this explains why satellites at smaller halo-centric radii are somewhat redder and somewhat more concentrated. In addition, the weak colour and concentration dependence of satellite galaxies on halo mass is simply a reflection of the fact that more massive haloes host, on average, more massive satellites. Combining these results with the fact that satellite galaxies are, on average, redder and somewhat more concentrated than central galaxies of the same stellar mass, the following picture emerges: galaxies become redder and somewhat more concentrated once they fall into a bigger halo (i.e., once they become a satellite galaxy). This is a clear manifestation of environment dependence. However, there is no indication that the magnitude of the transformation (or its timescale) depends on environment; a galaxy undergoes a transition when it becomes a satellite, but it does not matter whether it becomes a satellite of a small (Milky Way sized) halo, or of a massive cluster. We discuss the implication of this `dearth' of environment dependence for the physical processes responsible for transforming satellite galaxies.

Frank C. van den Bosch; Anna Pasquali; Xiaohu Yang; H. J. Mo; Simone Weinmann; Daniel H. McIntosh; Daniel Aquino
2008-05-01

89

SaVi: satellite constellation visualization

  CERN Preprints

Summary: SaVi, a program for visualizing satellite orbits, movement, and coverage, is maintained at the University of Surrey. This tool has been used for research in academic papers, and by industry companies designing and intending to deploy satellite constellations. It has also proven useful for demonstrating aspects of satellite constellations and their geometry, coverage and movement for educational and teaching purposes. SaVi is introduced and described briefly here.

Wood, Lloyd
2012-01-01

90

Origin of Europa and the Galilean Satellites

  CERN Preprints

Summary: Europa is believed to have formed near the very end of Jupiter's own accretion, within a circumplanetary disk of gas and solid particles. We review the formation of the Galilean satellites in the context of current constraints and understanding of giant planet formation, focusing on recent models of satellite growth within a circumjovian accretion disk produced during the final stages of gas inflow to Jupiter. In such a disk, the Galilean satellites would have accreted slowly, in more than 10^5 yr, and in a low pressure, low gas density environment. Gravitational interactions between the satellites and the gas disk lead to inward orbital migration and loss of satellites to Jupiter. Such effects tend to select for a maximum satellite mass and a common total satellite system mass compared to the planet's mass. One implication is that multiple satellite systems may have formed and been lost during the final stages of Jupiter's growth, with the Galilean satellites being the last generation that survived as gas in...

Canup, Robin M
2008-01-01

91

Satellites of the largest Kuiper belt objects

  Astrophysics (arXiv)

Summary: We have searched the four brightest objects in the Kuiper belt for the presence of satellites using the newly commissioned Keck Observatory Laser Guide Star Adaptive Optics system. Satellites are seen around three of the four objects: Pluto (whose satellite Charon is well-known), 2003 EL61, and 2003 UB313. The object 2005 FY9, the brightest Kuiper belt object after Pluto, does not have a satellite detectable within 0.4 arcseconds with a brightness of more than 0.5% of the primary. The presence of satellites to 3 of the 4 brightest Kuiper belt objects is inconsistent with the fraction of satellites in the Kuiper belt at large at the 99.1% confidence level, suggesting a different formation mechanism for these largest KBO satellites. The satellites of 2003 EL61 and 2003 UB313, with fractional brightnesses of 5% and 2% of their primaries, respectively, are significantly fainter relative to their primaries than other known Kuiper belt object satellites, again pointing to possible differences in their origin.

M. E. Brown; M. A. van Dam; A. H. Bouchez; D. Le Mignant; R. D. Campbell; J. C. Y. Chin; A. Conrad; S. K. Hartman; E. M. Johansson; R. E. Lafon; D. L. Rabinowitz; P. J. Stomski, Jr.; D. M. Summers; C. A. Trujillo; P. L. Wizinowich
2005-10-03

92

Origin of Europa and the Galilean Satellites

  Astrophysics (arXiv)

Summary: Europa is believed to have formed near the very end of Jupiter's own accretion, within a circumplanetary disk of gas and solid particles. We review the formation of the Galilean satellites in the context of current constraints and understanding of giant planet formation, focusing on recent models of satellite growth within a circumjovian accretion disk produced during the final stages of gas inflow to Jupiter. In such a disk, the Galilean satellites would have accreted slowly, in more than 10^5 yr, and in a low pressure, low gas density environment. Gravitational interactions between the satellites and the gas disk lead to inward orbital migration and loss of satellites to Jupiter. Such effects tend to select for a maximum satellite mass and a common total satellite system mass compared to the planet's mass. One implication is that multiple satellite systems may have formed and been lost during the final stages of Jupiter's growth, with the Galilean satellites being the last generation that survived as gas inflow to Jupiter ended. We conclude by discussing open issues and implications for Europa's conditions of formation.

Robin M. Canup; William R. Ward
2008-12-30

93

Satellites of the largest Kuiper belt objects

  CERN Preprints

Summary: We have searched the four brightest objects in the Kuiper belt for the presence of satellites using the newly commissioned Keck Observatory Laser Guide Star Adaptive Optics system. Satellites are seen around three of the four objects: Pluto (whose satellite Charon is well-known), 2003 EL61, and 2003 UB313. The object 2005 FY9, the brightest Kuiper belt object after Pluto, does not have a satellite detectable within 0.4 arcseconds with a brightness of more than 0.5% of the primary. The presence of satellites to 3 of the 4 brightest Kuiper belt objects is inconsistent with the fraction of satellites in the Kuiper belt at large at the 99.1% confidence level, suggesting a different formation mechanism for these largest KBO satellites. The satellites of 2003 EL61 and 2003 UB313, with fractional brightnesses of 5% and 2% of their primaries, respectively, are significantly fainter relative to their primaries than other known Kuiper belt object satellites, again pointing to possible differences in their origin.

Brown, M E; Bouchez, A H; Le Mignant, D; Campbell, R D; Chin, J C Y; Conrad, A; Hartman, S K; Johansson, E M; Lafon, R E; Rabinowitz, D L; Stomski, P J; Summers, D M; Trujillo, C A; Wizinowich, P L
2006-01-01

94

Characterizing switching problems in low earth orbit satellite constellations with satellite failures 

  Texas A&M University - TxSpace

Summary: CHARACTERIZING SWITCHING PROBLEMS IN LOW EARTH ORBIT SATELLITE CONSTELLATIONS WITH SATELLITE FAILURES A Thesis by BRANDON SCOTT WADSWORTH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1999 Major Subject: Computer Science CHARACTERIZING SWITCHING PROBLEMS IN LOW EARTH ORBIT SATELLITE CONSTELLATIONS WITH SATELLITE FAILURES A Thesis By BRANDON SCOTT WADSWORTH Submitted to Texas...

Wadsworth, Brandon Scott
1999-01-01

95

Satellite Services Rate Schedule Effective March 26, 2014

  Computer Technologies and Information Sciences Websites

Summary: Satellite Services Rate Schedule Effective March 26, 2014 SCPS offers satellite communications Satellite Services email satellite@virginia.edu or call 434-982-5268. Services UVa/State Regular* UVa Studio to Vyvx $335 $500 $400 $600 IFB & PL $15 $20 $20 $30 Tape Playback $65 $100 $85 $125 Satellite

Acton, Scott

96

National Satellite Technology Program Dr. Turki Al-Saud

  Engineering Websites

Summary: National Satellite Technology Program Dr. Turki Al-Saud KACST #12;National Satellite Technology Program Nano Satellites Program Remote Sensing Satellites Program Going big in size, weight and ambition (The GEO Program) #12;National Satellite Technology Program Space Research Institute (SRI

Stanford University

97

Secure Floating-Point Arithmetic and Private Satellite Collision Analysis

  Mathematics Websites

Summary: strategic satellites. On the other hand, satellites are a big investment and it is in every satellite owner of satellites is avail- able. These data can be analysed to predict collisions and hopefully react to the more objects and satellite This research was, in part, funded by the U.S. Government. The views and conclu


98

Ravens satellite mission concept study

  CERN Preprints

Summary: The concept for Ravens satellite mission was proposed in response to a CSA AO for potential Canadian mission contributions to the International Living With a Star (ILWS) program. Ravens was conceived of to fill an important gap in the ILWS program: global imaging. Ravens will build on the heritage of world-class global imaging carried out in Canada. It would do much more than provide global observations to complete the system level capabilities of ILWS. Ravens would be comprised of two satellites on elliptical polar orbits, relatively phased on those orbits to provide the first-ever continuous (ie., 24 hours per day 7 days per week) global imaging of the northern hemisphere auroral and polar cap regions. This would provide the first-ever unbroken sequences of global images of the auroral response during long duration geomagnetic processes like storms and steady magnetospheric convection events. Ravens could track the spatio-temporal evolution of the global electron and proton auroral distribution, and would o...

Donovan, Eric F
2011-01-01

99

Dynamics of the Galaxy's Satellites

  Astrophysics (arXiv)

Summary: The Milky Way's satellites provide unique information about the density of the Galactic halo at large radii. The inclusion of even a few rather inaccurate proper motions resolves an ambiguity in older mass estimates in favour of higher values. Many of the satellites are concentrated into streams. The dynamics of the Magellanic Stream provided an early indication that the halo reaches out to beyond 100 kpc. Tidal forces between the Clouds are currently disturbing the Clouds' internal dynamics. One would expect this damage to worsen rapidly as the tidal field of the MW excites the eccentricity of the Clouds' mutual orbit. This process, which has yet to be completely modelled, is important for understanding the degree of self-lensing in searches for gravitational lensing events. The Sagittarius Dwarf galaxy very likely contributes significantly to the Galactic warp. The direction of the warp's line of nodes is incorrectly predicted by the simplest models of the Dwarf's orbit. More sophisticated models, in which a complex distribution of stripped dark matter is predicted, may be more successful.

James Binney
2000-06-28

100

Fig.1. A hybrid network of MANET-satellite-Internet. Adaptive Hierarchical Resource Management for Satellite Channel in Hybrid MANET-

  Engineering Websites

Summary: MANET MANET MANET Service center Internet Satellite MANET MANET MANET Service center Internet Satellite Fig.1. A hybrid network of MANET-satellite-Internet. Adaptive Hierarchical Resource Management for Satellite Channel in Hybrid MANET- Satellite-Internet Network Nelson X. Liu Xiaoming Zhou John S. Baras

Baras, John S.

101

Using Satellite Data to Forecast . Bleaching Events

  Geosciences Websites

Summary: 1 Using Satellite Data to Forecast . Bleaching Events . By Tyler Christensen . NOAA Coral Reef Watch Satellite Imagery Worksheet The main condition that is linked to coral bleaching is unusually high for the warmest month. One degree above that is the threshold temperature for coral bleaching, shown as the solid


102

1, 337378, 2001 Modeling of satellite

  Computer Technologies and Information Sciences Websites

Summary: in monitoring of the chemical composition of the troposphere. The Total Ozone Mapping Spectrometer (TOMSACPD 1, 337­378, 2001 Modeling of satellite derived tropospheric ozone W. Peters et al. Title Page-transport modeling of the satellite observed distribution of tropical tropospheric ozone W. Peters1, M. Krol1, F

Boyer, Edmond

103

Modern Digital Satellite Television: How It Works

  Computer Technologies and Information Sciences Websites

Summary: diverse range of services. HDTV broadcast television. Backhaul applications, e.g., electronic newsModern Digital Satellite Television: How It Works Matthew C. Valenti Lane Department of Computer #12;Outline 1 Satellite Television Standards 2 DVB-S2 Modulation 3 LDPC Coding 4 Tricks for Improving

Valenti, Matthew C.

104

4, 68236836, 2004 A global satellite view

  Physics Websites

Summary: ACPD 4, 6823­6836, 2004 A global satellite view of aerosol cloud interactions C. Luo Title Page and Physics Discussions A global satellite view of aerosol cloud interactions C. Luo Institute for Computational Earth System Science, University of California, Santa Barbara, California 6832 Ellison Hall

Paris-Sud XI, Université de

105

Offshore wind resource assessment through satellite images

  Multidisciplinary Databases and Resources Websites

Summary: 1 Slide no. 4 Offshore wind resource assessment through satellite images Charlotte Bay Hasager Rev wind farm ·Demo of the Risø Wemsar Tool (RWT) #12;3 Slide no. Objective To use satellite SAR images for offshore wind ressource assessment in lieu of in-situ mast observations #12;4 Slide no


106

Numerical Homotopy Algorithms for Satellite Trajectory Control

  Mathematics Websites

Summary: Numerical Homotopy Algorithms for Satellite Trajectory Control by Pole Placement1 Jan Verschelde2 is to illustrate the application of numerical homotopy algorithms to control the trajectory of a satellite. We design output feedback laws via pole place- ment. The output feedback laws are computed by numerical

Verschelde, Jan

107

NASA Launches New Earth Observation Satellite

  Physics Websites

Summary: NASA Launches New Earth Observation Satellite Pg 3 Deciphering the Mysterious Math of the Solar Goddard View The Weekly ­ 2 NASA Launches New Earth Observation Satellite ­ 3 3-D printing Creates Complex Administration www.nasa.gov Volume 9 Issue 2 March 2013 #12;N ASA's Landsat Data Continuity Mission (LDCM) roared

Christian, Eric

108

Satellite Eye for Galathea 3 Annual Report 2006

  Multidisciplinary Databases and Resources Websites

Summary: .: 841-1124 Group's own reg. no.: 1130317-01 Environmental monitoring from satellite is among the most in satellite remote sensing. The satellite images reveal conditions and dynamical processes in the oceans


109

Cooperative Institute for Meteorological Satellite Studies University of Wisconsin -Madison

  Geosciences Websites

Summary: Cooperative Institute for Meteorological Satellite Studies University of Wisconsin - Madison Clouds from Satellites: from SMONEX to MODIS Steven A. Ackerman University of Wisconsin #12;Cooperative Institute for Meteorological Satellite Studies

Collett Jr., Jeffrey L.

110

Jupiter's Outer Satellites and Trojans David C. Jewitt

  Physics Websites

Summary: 12 Jupiter's Outer Satellites and Trojans David C. Jewitt Institute for Astronomy, University Institute 12.1 INTRODUCTION Jupiter's irregular satellites possess large, eccentric and highly inclined orbits. They are conventionally considered separately from the temporarily captured satellites

Jewitt, David C.

111

Stephen Volz Assistant Administrator for Satellite & Information Services

  Environmental Sciences and Ecology Websites

Summary: Stephen Volz Assistant Administrator for Satellite & Information Services National Oceanic and Atmospheric Administration (NOAA) Dr. Stephen Volz is the NOAA Assistant Administrator for Satellite and Information Services. NOAA's Satellite and Information Service is dedicated to providing timely access


112

A Feedback Implosion Suppression Algorithm for Satellite Reliable Multicast

  Engineering Websites

Summary: A Feedback Implosion Suppression Algorithm for Satellite Reliable Multicast Gun Akkor, John S. Baras, and Michael Hadjitheodosiou Center for Satellite and Hybrid Communication Networks, Institute multicast transport protocols operating over a satellite network. A reliable transport protocol needs

Baras, John S.

113

Earthquake Damage Identification using High-Resolution Satellite

  Engineering Websites

Summary: Earthquake Damage Identification using High-Resolution Satellite Images from the 2003 Northern & evaluation · High-resolution satellite imagery · Images from Boumerdes, Algeria · Semi-automated damage" for damage, maps, etc. · Satellite images can provide critical information to plan response

Shinozuka, Masanobu

114

Turbo-Coded APSK Modulations Design for Satellite Broadband Communications

  Computer Technologies and Information Sciences Websites

Summary: Turbo-Coded APSK Modulations Design for Satellite Broadband Communications Riccardo De Gaudenzi with application to satellite broad- band communications. APSK represents an attractive modulation format systems. 1 Introduction Satellite communication systems strength lies in their ability to efficiently

Guillén i Fàbregas, Albert

115

Capture of Irregular Satellites at Jupiter

  CERN Preprints

Summary: The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early Solar System instability when encounters between the outer planets occurred (Nesvorny, Vokrouhlicky & Morbidelli 2007, AJ 133; hereafter NVM07). NVM07 already showed that the irregular satellites of Saturn, Uranus and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary d...

Nesvorny, D; Deienno, R
2014-01-01

116

Sinking Satellites and Tilting Disk Galaxies

  Astrophysics (arXiv)

Summary: The infall of a satellite galaxy onto a galactic disk generally brings in angular momentum that is not aligned with the axis of the disk. The main dynamical issues addressed are what fraction of the orbital angular momentum of the satellite and the associated energy is added to the disk, as opposed to being left in the halo, and whether the absorbed fraction is added coherently or thermalized in the disk. By employing fully self-consistent disk+halo+satellite N-body simulations, we study the particular case of the satellite and main halo having similar density profiles, with internal velocities having the ``cosmological'' scaling $\\sigma\\propto M^{1/3}$. We find that most of the orbital angular momentum of the infalling satellite is left in the tidally stripped satellite remnants, with only $2\\%$, $6\\%$ and $9\\%$ of the orbital angular momentum being transferred to disks and halos for $10\\%$, $20\\%$ and $30\\%$ disk-mass satellites respectively. Because the disks are tilted by the infall of $10\\%$, $20\\%$ and $30\\%$ disk-mass satellites by angles of $(2.9\\pm0.3)^\\circ$, $(6.3\\pm0.1)^\\circ$ and $(9.7\\pm0.2)^\\circ$ respectively, the kinetic energy associated with the vertical motion in the initial coordinate frame of the three disks is respectively increased by $(6\\pm3)\\%$, $(26\\pm3)\\%$ and $(51\\pm5)\\%$ whereas the corresponding disk thermal energy associated with the vertical random motion in the tilted coordinate frame is only increased by $(4\\pm3)\\%$, $(6\\pm2)\\%$ and $(10\\pm2)\\%$, respectively. Under our initial conditions, a satellite having up to 20\\% of the disk mass would produce little observable thickening whereas a 30\\% disk-mass satellite produces little observable thickening inside the half-mass radius of the disk but great damage beyond the half-mass radius.

Siqin Huang; R. G. Carlberg
1995-11-16

117

The Orbital Distribution of Satellite Galaxies

  Astrophysics (arXiv)

Summary: We measure the distribution of velocities for prograde and retrograde satellite galaxies using a combination of published data and new observations for 78 satellites of 63 extremely isolated disc galaxies (169 satellites total). We find that the velocity distribution is non-Gaussian (>99.9% confidence), but that it can be described as the sum of two Gaussians, one of which is broad (sigma = 176 \\pm 15 km/s), has a mean prograde velocity of 86 \\pm 30 km/s, and contains ~55% of the satellites, while the other is slightly retrograde with a mean velocity of -21 \\pm 22 km/s and sigma = 74 \\pm 18 km/s and contains ~45% of the satellites. Both of these components are present over all projected radii and found in the sample regardless of cuts on primary inclination or satellite disc angle. The double-Gaussian shape, however, becomes more pronounced among satellites of more luminous primaries. We remove the potential dependence of satellite velocity on primary luminosity using the Tully-Fisher relation and still find the velocity distribution to be asymmetric and even more significantly non-Gaussian. The asymmetric velocity distribution demonstrates a connection between the inner, visible disc galaxy and the kinematics of the outer, dark halo. The reach of this connection, extending even beyond the virial radii, suggests that it is imprinted by the satellite infall pattern and large-scale effects, rather than by higher-level dynamical processes in the formation of the central galaxy or late-term evolution of the satellites.

Stéphane Herbert-Fort; Dennis Zaritsky; Yeun Jin Kim; Jeremy Bailin; James E. Taylor
2007-11-26

118

Short Communication Satellite tracking highlights difficulties in the design

  Environmental Sciences and Ecology Websites

Summary: Short Communication Satellite tracking highlights difficulties in the design of effective protected are concentrated near neritic breeding and nesting grounds. We used satellite telemetry to de- scribe patterns

Exeter, University of

119

Satellites around massive galaxies since z~2

  CERN Preprints

Summary: Accretion of minor satellites has been postulated as the most likely mechanism to explain the significant size evolution of the massive galaxies over cosmic time. Using a sample of 629 massive (Mstar~10^11 Msun) galaxies from the near-infrared Palomar/DEEP-2 survey, we explore which fraction of these objects has satellites with 0.01 Msat < Mcentral < 1 (1:100) up to z=1 and which fraction has satellites with 0.1 Msat < Mcentral < 1 (1:10) up to z=2 within a projected radial distance of 100 kpc. We find that the fraction of massive galaxies with satellites, after the background correction, remains basically constant and close to ~30% for satellites with a mass ratio down to 1:100 up to z=1, and ~15% for satellites with a 1:10 mass ratio up to z=2. The family of spheroid-like massive galaxies presents a 2-3 times larger fraction of objects with satellites than the group of disk-like massive galaxies. A crude estimation of the number of 1:3 mergers a massive spheroid-like galaxy experiences since z~2...

Mármol-Queraltó, E; Pérez-González, P G; Varela, J; Barro, G
2012-01-01

120

Probing Dark Matter Haloes with Satellite Kinematics

  Astrophysics (arXiv)

Summary: Using detailed mock galaxy redshift surveys we investigate to what extent the kinematics of large samples of satellites galaxies extracted from flux-limited surveys can be used to constrain halo masses. Previous host-satellite selection criteria yield relatively large fractions of interlopers and with a velocity distribution that, contrary to what has typically been assumed, differs strongly from uniform. A new adaptive selection criterion is proposed which yields much larger host-satellite samples and with strongly reduced interloper fractions. We show that satellite weighting, which occurs naturally when stacking many host-satellite pairs, introduces a bias towards higher velocity dispersions compared to the true, host-averaged mean. A further bias, in the same direction, is introduced when using flux-limited, rather than volume-limited surveys. We apply our adaptive selection criterion to the 2dFGRS and obtain a sample of 12613 satellite galaxies and 8004 host galaxies. The satellite kinematics are in excellent agreement with predictions based on the conditional luminosity function (CLF), providing independent, dynamical confirmation of the average mass-to-light ratios predicted by the CLF formalism.

Frank C. van den Bosch; Peder Norberg; H. J. Mo; Xiaohu Yang
2004-05-14

121

Gas Shepherding by an Infalling Satellite

  Astrophysics (arXiv)

Summary: I calculate the action of a satellite, infalling through dynamical friction, on a coplanar gaseous disk of finite radial extent. The disk tides, raised by the infalling satellite, couple the satellite and disk. Dynamical friction acting on the satellite then shrinks the radius of the coupled satellite-disk system. Thus, the gas is ``shepherded'' to smaller radii. In addition, gas shepherding produces a large surface density enhancement at the disk edge. If the disk edge then becomes gravitationally unstable and fragments, it may give rise to enhanced star formation. On the other hand, if the satellite is sufficiently massive and dense, the gas may be transported from $\\sim 100$ pc to inside of a 10 to 10s of parsecs before completely fragmenting into stars. I argue that gas shepherding may drive the fueling of active galaxies and central starbursts and I compare this scenario to competing scenarios. I argue that sufficiently large and dense super star clusters (acting as the shepherding satellites) can shepherd a gas disk down to ten to tens of parsecs. Inside of ten to tens of parsecs, another mechanism may operate, i.e., cloud-cloud collisions or a marginally (gravitationally) stable disk, that drives the gas $\\lesssim 1$ pc, where it can be viscously accreted, feeding a central engine.

P. Chang
2008-05-22

122

Luminous satellite galaxies in gravitational lenses

  Astrophysics (arXiv)

Summary: Substructures, expected in cold dark matter haloes, have been proposed to explain the anomalous flux ratios in gravitational lenses. About 25% of lenses in the Cosmic Lens All-Sky Survey (CLASS) appear to have luminous satellites within ~ 5 kpc/h of the main lensing galaxies, which are usually at redshift z ~ 0.2-1. In this work we use the Millennium Simulation combined with galaxy catalogues from semi-analytical techniques to study the predicted frequency of such satellites in simulated haloes. The fraction of haloes that host bright satellites within the (projected) central regions is similar for red and blue hosts and is found to increase as a function of host halo mass and redshift. Specifically, at z = 1, about 11% of galaxy-sized haloes (with masses between 10^{12} M_sun/h and 10^{13} M_sun/h) host bright satellite galaxies within a projected radius of 5 kpc/h. This fraction increases to about 17% (25%) if we consider bright (all) satellites of only group-sized haloes (with masses between 10^{13} M_sun/h and 10^{14} M_sun/h). These results are roughly consistent with the fraction (~ 25%) of CLASS lensing galaxies observed to host luminous satellites. At z = 0, only ~ 3% of galaxy-sized haloes host bright satellite galaxies. The fraction rises to ~ 6%, (10%) if we consider bright (all) satellites of only group-sized haloes at z = 0. However, most of the satellites found in the inner regions are `orphan' galaxies where the dark matter haloes have been completely stripped. Thus the agreement crucially depends on the true survival rate of these `orphan' galaxies. We also discuss the effects of numerical resolution and cosmologies on our results.

S. E. Bryan; S. Mao; S. T. Kay
2008-09-18

123

Star Formation Histories of the Galactic Satellites

  Astrophysics (arXiv)

Summary: Late accretion models for formation of the Galactic halo require that many Galactic satellite galaxies have been cannibalised into the halo field. Comparison of the metallicity and age distribution function of stars in the surviving satellites with the apparently exclusively old stars in the field halo can constrain the importance of any such process. We have developed a new objective technique to determine star formation histories in dSph galaxies. We apply this technique to the surviving Galactic satellites, deducing an approximately uniform distribution of ages for the constituents, quite unlike the halo field stars. Thus, late accretion did not play a substantial part in Galactic halo formation.

Gerard Gilmore; Xavier Hernandez; David Valls-Gabaud
1999-10-26

124

Disruption of satellites in cosmological haloes

  Astrophysics (arXiv)

Summary: We investigate how the survival of dark matter satellites inside virialized halos depends on tidal stripping and dynamical friction. We use an analytic approach and then compare the results with N-Body simulations. Both the satellites and the primary halos are similar to cosmological haloes and have NFW density profiles. Satellites can either merge with the primary halo or continue to move on barely perturbed orbits, eventually being disrupted, depending on the relative strength of friction and tidal forces. We propose that their actual fate depends simply on their mass ratio relative to the primary halo.

Giuliano Taffoni; Lucio Mayer; Monica Colpi; Fabio Governato
2001-09-03

125

Satellite galaxies in cosmological dark matter halos

  Astrophysics (arXiv)

Summary: We present preliminary results from a series of high-resolution N-body simulations that focus on 8 dark matter halos each of order a million particles within the virial radius. We follow the time evolution of hundreds of individually tracked satellite galaxies and relate their physical properties to the differing halo environmental conditions. Our main science driver is to understand how satellite galaxies lose their mass and react to tidal stripping. Unlike previous work our results are performed in a fully self-consistent cosmological context. The preliminary results demonstrate that while environment may vary considerably with respects to formation time and richness of substructure, the satellites evolve similarly.

Stuart P. D. Gill; Alexander Knebe; Brad K. Gibson
2003-11-28

126

Star Formation in Satellite Galaxies

  CERN Preprints

Summary: We present narrow-band observations of the H$\\alpha$ emission in a sample of 31 satellite orbiting isolated giant spiral galaxies. The sample studied spans the range $-19

Gutíerrez, C M; Funes, J G; Ribeiro, M B
2006-01-01

127

The Transiting Exoplanet Survey Satellite

  CERN Preprints

Summary: The Transiting Exoplanet Survey Satellite (TESS) will search for planets transiting bright and nearby stars. TESS has been selected by NASA for launch in 2017 as an Astrophysics Explorer mission. The spacecraft will be placed into a highly elliptical 13.7-day orbit around the Earth. During its two-year mission, TESS will employ four wide-field optical CCD cameras to monitor at least 200,000 main-sequence dwarf stars with I<13 for temporary drops in brightness caused by planetary transits. Each star will be observed for an interval ranging from one month to one year, depending mainly on the star's ecliptic latitude. The longest observing intervals will be for stars near the ecliptic poles, which are the optimal locations for follow-up observations with the James Webb Space Telescope. Brightness measurements of preselected target stars will be recorded every 2 min, and full frame images will be recorded every 30 min. TESS stars will be 10-100 times brighter than those surveyed by the pioneering Kepler missio...

Ricker, George R; Vanderspek, Roland; Latham, David W; Bakos, Gaspar A; Bean, Jacob L; Berta-Thompson, Zachory K; Brown, Timothy M; Buchhave, Lars; Butler, Nathaniel R; Butler, R Paul; Chaplin, William J; Charbonneau, David; Christensen-Dalsgaard, Jorgen; Clampin, Mark; Deming, Drake; Doty, John; De Lee, Nathan; Dressing, Courtney; Dunham, E W; Endl, Michael; Fressin, Francois; Ge, Jian; Henning, Thomas; Holman, Matthew J; Howard, Andrew W; Ida, Shigeru; Jenkins, Jon; Jernigan, Garrett; Johnson, John Asher; Kaltenegger, Lisa; Kawai, Nobuyuki; Kjeldsen, Hans; Laughlin, Gregory; Levine, Alan M; Lin, Douglas; Lissauer, Jack J; MacQueen, Phillip; Marcy, Geoffrey; McCullough, P R; Morton, Timothy D; Narita, Norio; Paegert, Martin; Palle, Enric; Pepe, Francesco; Pepper, Joshua; Quirrenbach, Andreas; Rinehart, S A; Sasselov, Dimitar; Sato, Bun'ei; Seager, Sara; Sozzetti, Alessandro; Stassun, Keivan G; Sullivan, Peter; Szentgyorgyi, Andrew; Torres, Guillermo; Udry, Stephane; Villasenor, Joel
2014-01-01

128

The MAP Satellite Feed Horns

  Astrophysics (arXiv)

Summary: We present the design, manufacturing methods, and characterization of 20 microwave feed horns currently in use on the Microwave Anisotropy Probe (MAP) satellite. The nature of the cosmic microwave background (CMB) anisotropy requires a detailed understanding of the properties of every optical component of a microwave telescope. In particular, the properties of the feeds must be known so that the forward gain and sidelobe response of the telescope can be modeled and so that potential systematic effects may be computed. MAP requires low emissivity, azimuthally symmetric, low-sidelobe feeds in five microwave bands (K, Ka, Q, V, and W) that fit within a constrained geometry. The beam pattern of each feed is modeled and compared with measurements; the agreement is generally excellent to the -60 dB level (80 degrees from the beam peak). This agreement verifies the beam-predicting software and the manufacturing process. The feeds also affect the properties and modeling of the microwave receivers. To this end, we show that the reflection from the feeds is less than -25 dB over most of each band and that their emissivity is acceptable. The feeds meet their multiple requirements.

C. Barnes; M. Limon; L. Page; C. Bennett; S. Bradley; M. Halpern; G. Hinshaw; N. Jarosik; W. Jones; A. Kogut; S. Meyer; O. Motrunich; G. Tucker; D. Wilkinson; E. J. Wollack
2003-01-10

129

Dark Satellites and Cosmic Reionization

  Astrophysics (arXiv)

Summary: A possible explanation of the present discrepancy between the abundance of galactic subhaloes predicted by N-Body simulations with those observed in the Local Group is presented. We study the impact of an early reionization on the baryonic component of the Universe using SPH simulations on group and galactic scales. We use a simplified model for reionization described as an instantaneous increment of the IGM temperature (with 1e5 8). We find that a key role is played by compton cooling (interaction between hot electrons and the CMB photons); at high redshift (z_r>10) this cooling is very efficient and it is able to counteract any heating of the gas within few Myrs. This means that a late reionization is needed (z_r<9) to sufficiently reduce the number of luminous dwarf satellites around our Galaxy. For a reionization redshift z_r=8 and a reionization temperature of T_{IGM}~1e5 K we are able to reproduce the observed number of Local Group dwarf galaxies in our simulations.

Andrea V. Maccio'; Ben Moore; Joachim Stadel; Doug Potter
2006-09-06

130

Emerging trends in the satellite industry

  MIT - DSpace

Summary: Risk aversion in the satellite industry has fostered long development cycles and low rates of innovation in the past. Emerging trends in propulsion technology development and spacecraft architecture design could lead to ...

Salazar, Vagn Knudsen
2012-01-01

131

Resource management for advanced transmission antenna satellites

  MIT - DSpace

Summary: In satellite communications, narrow spotbeams can provide high power and data rates to the desired location while reducing spatial interference. Advanced transmission antenna technology is critical to generate and switch ...

Chan, Vincent W. S.

132

Atmospheric delay modeling for satellite laser altimetry

  MIT - DSpace

Summary: NASA's Ice, Cloud, and Land Elevation Satellite (ICESat) is a laser altimetry mission with the primary purpose of measuring the mass balance of the ice sheets of Greenland and Antarctica. It will provide 5 years of topography ...

Quinn, Katherine J. (Katherine Jane), 1971-
2002-01-01

133

Simulation Methodologies for Satellite Solar Array Dynamics

  Texas A&M University - TxSpace

Summary: The purpose of the present thesis is to furnish diverse studies on the dynamic response of satellite solar arrays. The term flexible structure or, briefly, structure has different interpretations and definitions, depending on source...

Mohsenizadeh, Navid
2010-07-16

134

Dynamics and control of electromagnetic satellite formations

  MIT - DSpace

Summary: Satellite formation flying is an enabling technology for many space missions, especially for space-based telescopes. Usually there is a tight formation-keeping requirement that may need constant expenditure of fuel or at ...

Ahsun, Umair, 1972-
2007-01-01

135

The Formation of Pluto's Low Mass Satellites

  CERN Preprints

Summary: Motivated by the New Horizons mission, we consider how Pluto's small satellites -- currently P5, Nix, P4, and Hydra -- grow in debris from the giant impact that forms the Pluto-Charon binary or in solid material captured from the protoplanetary debris disk. If the satellites have masses close to their minimum masses, our analysis suggests that capture of material into a circumplanetary or circumbinary debris disk is a viable mechanism for satellite formation. If the satellites are more massive, they probably form in debris from the giant impact. After the impact, Pluto and Charon accrete some of the debris and eject the rest from the binary orbit. During the ejection, high velocity collisions among debris particles produce a collisional cascade, leading to the ejection of some debris from the system and enabling the remaining debris particles to find stable orbits around the binary. Our numerical simulations of viscous diffusion, coagulation, and migration show that collisional evolution within a ring or disk...

Kenyon, Scott J
2013-01-01

136

Anisotropies in the Distribution of Satellite Galaxies

  Astrophysics (arXiv)

Summary: We find that satellites of isolated disk galaxies at projected radii between 300 and 500 kpc are distributed asymmetrically about the parent galaxy and aligned preferentially with the disk minor axis. The dynamical timescale at these radii is sufficiently long that the shape of this distribution must reflect the formation history of the outer halo rather than its internal evolution. We also find that the orbital angular momenta of satellites at projected major axis distances of $\\ltsim$ 200 kpc tend to align with that of the central disk. These results demonstrate that satellites are dynamically related to their primary galaxy. Satellites drawn from current simulations of hierarchical galaxy formation exhibit neither the systematic alignment nor the net rotation with the central disk that we find in the data.

Dennis Zaritsky; Rodney Smith; Carlos S. Frenk; Simon D. M. White
1996-11-26

137

Satellite-based quantum clock synchronization

  Quantum Physics (arXiv)

Summary: We propose a practical scheme of satellite-based quantum clock synchronization with atmospheric dispersion cancellation and by taking into account spacetime background of the Earth. Two frequency entangled pulses are employed to synchronize two clocks, one at a ground station and the other at a satellite. The time discrepancy of the two clocks is introduced into the pulses by moving mirrors and is extracted by measuring the coincidence rate of the pulses in the interferometer. We find that the pulses are distorted due to effects of gravity when they propagate between the Earth and the satellite, resulting in coincidence rate are remarkably affected. We also find that the precision of the clock synchronization are sensitive to the source parameters and the altitude of the satellite. Our proposal can be realized with current technology.

Jieci Wang; Zehua Tian; Jiliang Jing; Heng Fan
2015-01-26

138

Synthetic Aperture Radar Interferometry with 3 satellites

  MIT - DSpace

Summary: Our study investigates interferometric SAR (InSAR) post-processing height retrieval techniques. We explore the possible improvements by adding a third satellite to the two already in orbit, and examine some potential uses ...

Wong, Wallace D. (Wallace Dazheng)
2005-01-01

139

Satellite streamfunction analysis for the California current

  Texas A&M University - TxSpace

Summary: Page ABSTRACT ACKNOWLEDGMENTS TABLE OF CONTENTS LIST OF FIGURES nl via I. INTRODUCTION A. California Current B. Satellite Instruments C. Satellite Mesoscale Studies D. Objective 1 2 3 7 II. THEORY A. Streamfunction Representation B... on identification and analysis of dynamical processes which govern wind-driven motion over the shelf. It is dear from these studies that a complex mesoscale boundary regime arises seaward of the west coast in response to episodic atmospheric and oceanic forcing...

Arango, Hernan Guillermo
1987-01-01

140

Satellite streamfunction analysis for the California current 

  Texas A&M University - TxSpace

Summary: SATELLITE STREAMFUNCTION ANALYSIS FOR THE CALIFORNIA CURRENT A Thesis by HERNAN GUILLERMO ARANGO Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August... 1987 Major Subject: Oceanography SATELLITE STREAMFUNCTION ANALYSIS FOR THE CALIFORNIA CURRENT A Thesis by HERNAN GUILLERMO ARANGO Approved as to style and content by Andrew C. Vastano (Chairman of Committee) Robert O. Reid (Member) Geor e L...

Arango, Hernan Guillermo
1987-01-01

141

Atmospheric structure determined from satellite data

  Texas A&M University - TxSpace

Summary: ATMOSPHERIC STRUCTURE DETERMINED PROM SATELLITE DATA A Thesis KEITN SHELBURNE ~IGHT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1978 Major... Subject: Meteorology ATM)SPHERIC STRUCTURE DETEiUIINED FRDM SATELLITE DATA A Thesis XEITH SHELBURNE KNIGHT Approved as to style and content. hyi (Chairman of Cor ' iee) C. (Head of Department) (Miemher) ABSTRACT Atmospheric Structure Determined...

Knight, Keith Shelburne
1978-01-01

142

The Anisotropic Distribution of Satellite Galaxies

  Astrophysics (arXiv)

Summary: We identify satellites of isolated galaxies in SDSS and examine their angular distribution. Using mock catalogues generated from cosmological N-body simulations, we demonstrate that the selection criteria used to select isolated galaxies and their satellites must be very strict in order to correctly identify systems in which the primary galaxy dominates its environment. The criteria used in many previous studies instead select predominantly group members. We refine a set of selection criteria for which the group contamination is estimated to be less than 7% and present a catalogue of the resulting sample. The angular distribution of satellites about their host is biased towards the major axes for spheroidal galaxies and probably also for red disc galaxies, but is isotropic for blue disc galaxies, i.e. it is the colour of the host that determines the distribution of its satellites rather than its morphology. The similar anisotropy measured in this study as in studies that were dominated by groups implies that group-specific processes are not responsible for the angular distribution. Satellites that are most likely to have been recently accreted show a tendancy to lie along the same axis as the surrounding large scale structure. The orientations of isolated early and intermediate-type galaxies also align with the surrounding large scale structures. We discuss the origin of the anisotropic satellite distribution and consider the implications of our results, critically assessing the respective roles played by the orientation of the visible galaxy within its dark matter halo; anisotropic accretion of satellites from the larger scale environment; and the biased nature of satellites as tracers of the underlying dark matter subhalo population. (Abridged)

Jeremy Bailin; Chris Power; Peder Norberg; Dennis Zaritsky; Brad K. Gibson
2008-08-12

143

Atmospheric structure determined from satellite data 

  Texas A&M University - TxSpace

Summary: ATMOSPHERIC STRUCTURE DETERMINED PROM SATELLITE DATA A Thesis KEITN SHELBURNE ~IGHT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1978 Major... Subject: Meteorology ATM)SPHERIC STRUCTURE DETEiUIINED FRDM SATELLITE DATA A Thesis XEITH SHELBURNE KNIGHT Approved as to style and content. hyi (Chairman of Cor ' iee) C. (Head of Department) (Miemher) ABSTRACT Atmospheric Structure Determined...

Knight, Keith Shelburne
1978-01-01

144

A Satellite Mission Control System Brian Schmidt Hermansen

  Mathematics Websites

Summary: communication with the satellite and the Ground Station is the tracking and maintaining of the communicationA Satellite Mission Control System Brian Schmidt Hermansen Kongens Lyngby 2006 IMM­THESIS­2006 to and then use to communication with a given satellite. This means that one can service more than one satellite


145

A Satellite Mission Control System Brian Schmidt Hermansen

  Mathematics Websites

Summary: communication with the satellite and the Ground Station is the tracking and maintaining of the communicationA Satellite Mission Control System Brian Schmidt Hermansen Kongens Lyngby 2006 IMM-THESIS-2006 to and then use to communication with a given satellite. This means that one can service more than one satellite


146

Ion Micro-Propulsion and Cost Modeling for Satellite Clusters

  Engineering Websites

Summary: Ion Micro-Propulsion and Cost Modeling for Satellite Clusters b y Gregory Yashko B.S. Aerospace;3 Ion Micro-Propulsion and Cost Modeling for Satellite Clusters b y Gregory Yashko Submitted modeling of distributed satellite systems, determination of propulsion system requirements for satellite


147

SAMISCTM/MJFF Satellite Meeting 22 February/S Murphy

  Mathematics Websites

Summary: SAMISCTM/MJFF Satellite Meeting 22 February/S Murphy ISCTM/MJFF Satellite Meeting 22 February of AIDS are a form of adaptive txt strategy Individualized interventions #12;SAMISCTM/MJFF Satellite Meeting 22 February/S Murphy ISCTM/MJFF Satellite Meeting 22 February/S Murphy 2 2 Outline · Why Adaptive

Murphy, Susan A.

148

Joint Polar Satellite System Science Seminar Annual Digest

  Environmental Sciences and Ecology Websites

Summary: iii Joint Polar Satellite System Science Seminar Annual Digest 2013 #12;#12;Joint Polar Satellite Polar Satellite System (JPSS) Program Science, it is my pleasure to present this digest, which to ensuring that its user community is prepared to utilize the satellite imagery and data available from JPSS


149

Studying the Ocean CIOSSCooperative Institute for Oceanographic Satellite Studies

  Geosciences Websites

Summary: Studying the Ocean from Space CIOSSCooperative Institute for Oceanographic Satellite Studies #12;CIOSSCooperative Institute for Oceanographic Satellite Stud-What CIOSS Does CIOSS research helps develop our present and past satellites and helping plan future satellite sensors. CIOSS performs research that helps

Kurapov, Alexander

150

Correspondence SATELLITE AND SURFACE TEMPERATURE DATA AT ODDS?

  Environmental Sciences and Ecology Websites

Summary: Correspondence SATELLITE AND SURFACE TEMPERATURE DATA AT ODDS? Reply to John R. Christy and Roy WNider (1994), a perception has been created in the popular media that satellite measurements of global environmental changes. We discuss key aspects of the satellite vs. surface and the satellite vs. model issues

Fridlind, Ann

151

Satellite Diversity Gain Over The LEOS Channel, Based CDMA Systems

  Computer Technologies and Information Sciences Websites

Summary: Satellite Diversity Gain Over The LEOS Channel, Based CDMA Systems Tarek Attia, Peter Sweeney: There is a trend for mobile satellite system architectures aimed at the deployment of multi-satellite cost and having low power demand. In present and next generation satellite systems, CDMA has been

Haddadi, Hamed

152

Using Satellite Observations in Regional Scale Calculations of Carbon Exchange

  Environmental Sciences and Ecology Websites

Summary: Chapter 15 Using Satellite Observations in Regional Scale Calculations of Carbon Exchange Shaun.1 Introduction: How Satellite Data Can Interact with Carbon Exchange Calculations Estimates of carbon exchange. 2003). Satellite data can play an important part in such schemes, since satellite sensors provide

Jones, Peter JS

153

ANALYSIS OF HANDOVER CHARACTERISTICS IN SHADOWED LEO SATELLITE COMMUNICATION NETWORKS

  Engineering Websites

Summary: ANALYSIS OF HANDOVER CHARACTERISTICS IN SHADOWED LEO SATELLITE COMMUNICATION NETWORKS£ YOUNG HOON In the near future low earth orbit (LEO) satellite communication networks will partially substitute for fixed, ongoing calls may be dropped if satellite channels are shadowed. Therefore, in most LEO satellite

Sung, Dan Keun

154

Lattice Formation in Space for a Swarm of Pico Satellites

  Computer Technologies and Information Sciences Websites

Summary: Lattice Formation in Space for a Swarm of Pico Satellites Carlo Pinciroli1 , Mauro Birattari1.izzo}@esa.int Abstract. We present a distributed control strategy that lets a swarm of satellites autonomously form the satellites around a predefined meeting point, and a local term that allows a satellite to place itself

Vinko, Tamas

155

1. INTRODUCTION Satellite Doppler navigation, developed between 1957

  Engineering Websites

Summary: 1. INTRODUCTION Satellite Doppler navigation, developed between 1957 Theoretical Bounds on and 1963. At Random Erro rs i n Satellite least three different satellite systems provide Doppler navigation: 1) the U, geodesy and surveying; 2) the French ARGOS system, on board the U.S. TIROS satellites, which is used

Levanon, Nadav

156

Reducing Retransmissions in Point-to-point Satellite Transmissions

  Physics Websites

Summary: This paper deals with reliable unicast transmissions using a satellite communication system. SatelliteReducing Retransmissions in Point-to-point Satellite Transmissions J´er^ome Lacan and Tanguy P of the time, 40% up to 95% less. Such a mechanism is clearly useful in satellite contexts. I. Introduction

Paris-Sud XI, Université de

157

Small Satellite Missions Designed, Built, Tested, and Operated by LASP

  Geosciences Websites

Summary: Small Satellite Missions Designed, Built, Tested, and Operated by LASP LASP designs and operates diverse satellite missions and is available to partner on future small satellite missions. We offer a one-stop-shop of services and have the expertise to support all your small satellite development and operations needs. LASP

Mojzsis, Stephen J.

158

Why do Earth satellites stay up?

  CERN Preprints

Summary: Satellites in low Earth orbits must accurately conserve their orbital eccentricity, since a decrease in perigee of only 5-10% would cause them to crash. However, these satellites are subject to gravitational perturbations from the Earth's multipole moments, the Moon, and the Sun that are not spherically symmetric and hence do not conserve angular momentum, especially over the tens of thousands of orbits made by a typical satellite. Why then do satellites not crash? We describe a vector-based analysis of the long-term behavior of satellite orbits and apply this to several toy systems containing a single non-Keplerian perturbing potential. If only the quadrupole potential from the Earth's equatorial bulge is present, all near-circular orbits are stable. If only the octupole potential is present, all such orbits are unstable. If only the lunar or solar potential is present, all near-circular orbits with inclinations to the ecliptic exceeding 39 degrees are unstable. We describe the behavior of satellites in the ...

Tremaine, Scott
2013-01-01

159

Formation and evolution of Pluto's small satellites

  CERN Preprints

Summary: Pluto's system of 5 known satellites are in a puzzling orbital configuration. Each of the four small satellites are on low-eccentricity and low-inclination orbits situated near a mean motion resonance with the largest satellite Charon. The Pluto-Charon binary likely formed as a result of a giant impact and so the simplest explanation for the small satellites is that they accreted from debris of that collision. The Pluto-Charon binary has evolved outward since its formation due to tidal forces, which drove them into their current doubly synchronous state. Meanwhile, leftover debris from the formation of Charon was not initially distant enough from Pluto-Charon to explain the orbits of the current small satellites. The outstanding problems of the system are the movement of debris outward and the small satellites location near mean motion resonances with Charon. This work explores the dynamical behavior of collisionally interacting debris orbiting the Pluto-Charon system. While this work specifically tests initi...

Walsh, Kevin J
2015-01-01

160

Measuring Mass Loss Rates from Galactic Satellites

  Astrophysics (arXiv)

Summary: We present the results of a study that uses numerical simulations to interpret observations of tidally disturbed satellites around the Milky Way. When analysing the simulations from the viewpoint of an observer, we find a break in the slope of the star count and velocity dispersion profiles in our models at the location where unbound stars dominate. We conclude that `extra-tidal' stars and enhanced velocity dispersions observed in the outskirts of Galactic satellites are due to contamination by stellar debris from the tidal interaction with the Milky Way. However, a significant bound population can exist beyond the break radius and we argue that it should not be identified with the tidal radius of the satellite. We also develop and test a method for determining the mass loss rate from a Galactic satellite using its extra-tidal population. We apply this method to observations of globular clusters and dwarf spheroidal satellites of the Milky Way, and conclude that a significant fraction of both satellite systems are likely be destroyed within the next Hubble time. Finally, we demonstrate that this mass loss estimate allows us to place some limits on the initial mass function (IMF) of stars in a cluster from the radial dependence of its present day mass function (PDMF).

Kathryn V. Johnston; Steinn Sigurdsson; Lars Hernquist
1998-05-21

161

Star Formation in Satellite Galaxies

  Astrophysics (arXiv)

Summary: We present narrow-band observations of the H$\\alpha$ emission in a sample of 31 satellite orbiting isolated giant spiral galaxies. The sample studied spans the range $-19

C. M. Gutierrez; M. S. Alonso; J. G. Funes; M. B. Ribeiro
2006-04-14

162

L'ARN satellite du virus de la mosaque du concombre II. Etude de la relation virus-ARN satellite

  Physics Websites

Summary: L'ARN satellite du virus de la mosaïque du concombre II. Etude de la relation virus-ARN satellite de Recherches d'Avignon, F 84140 Montfavet. RÉSUMÉ Le lien entre la présence d'ARN-5 (ARN satellite isolats d'ARN satellite. concombre, Une dose de 5 x 10-' >g/ml (dose minimale) d'ARN-5 est requise pour

Paris-Sud XI, Université de

163

Heat Transfer -1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with

  Computer Technologies and Information Sciences Websites

Summary: Heat Transfer - 1 A satellite in space orbits the sun. The satellite can be approximated as a flat the sun is a blackbody with radius and surface temperature given below. (25 %) (b) The satellite perpendicular to the radiation coming from the sun. Assuming the satellite is at a uniform temperature, find

Virginia Tech

164

Why satellite networking often isn't really satellite networking, and what can be done about it

  Engineering Websites

Summary: LECTURE Why satellite networking often isn't really satellite networking, and what can be done about it: moving satellites towards a fuller networking role. Lloyd Wood Global Defense and Space Group, Cisco Systems Abstract Networking via satellites is currently done by a range of separate, non

Wood, Lloyd

165

Where are the missing galactic satellites?

  Astrophysics (arXiv)

Summary: Using published data, we have compiled the circular velocity (Vc) distribution function (VDF) of galaxy satellites in the Local Group. We find that within the volumes of radius of 570 kpc (400/h kpc for h=0.7) centered on the Milky Way and Andromeda, the average VDF is roughly approximated as n(>Vc)~ 45(Vc/10 km/s)^{-1} h^3 Mpc^{-3} for Vc in the range ~10-70 km/s. The observed VDF is compared with results of high-resolution cosmological simulations. We find that the VDF in models is very different from the observed one: n(>Vc)~1200(Vc/10 km/s)^{-2.75}h^3 Mpc^{-3}. Cosmological models thus predict that a halo of the size of our Galaxy should have about 50 dark matter satellites with circular velocity >20 km/s and mass >3x10^8/h Msun within a 570 kpc radius. This number is significantly higher than the approximate dozen satellites actually observed around our Galaxy. The observed and predicted VDFs cross at ~50 km/s, indicating that the predicted abundance of satellites with Vc> 50 km/s is in reasonably good agreement with observations. We conclude, therefore, that unless a large fraction of the Local Group satellites has been missed in observations, there is a dramatic discrepancy between observations and hierarchical models, regardless of the model parameters. We discuss several possible explanations for this discrepancy including identification of some satellites with the High Velocity Clouds observed in the Local Group, and the existence of dark satellites that failed to accrete gas and form stars due either to the expulsion of gas in the supernovae-driven winds or to gas heating by the intergalactic ionizing background. (Abridged)

Anatoly A. Klypin; Andrey V. Kravtsov; Octavio Valenzuela; Francisco Prada
1999-01-21

166

The satellite distribution of M31

  Astrophysics (arXiv)

Summary: (Abridged) The spatial distribution of the Galactic satellite system plays an important role in Galactic dynamics and cosmology, where its successful reproduction is a key test of simulations of galaxy halo formation. Here, we examine its representative nature by conducting an analysis of the 3-dimensional spatial distribution of the M31 subgroup of galaxies. We begin by a discussion of distance estimates and incompleteness concerns, before revisiting the question of membership of the M31 subgroup. Comparison of the distribution of M31 and Galactic satellites relative to the galactic disks suggests that the Galactic system is probably modestly incomplete at low latitudes by ~20%. We find that the radial distribution of satellites around M31 is more extended than the Galactic subgroup; 50% of the Galactic satellites are found within ~100kpc of the Galaxy, compared to ~200kpc for M31. We search for ``ghostly streams'' of satellites around M31, in the same way others have done for the Galaxy, and find several. The lack of M31-centric kinematic data, however, means we are unable to probe whether these streams represent real physical associations. Finally, we find that the M31 satellites are asymmetrically distributed with respect to our line-of-sight to this object, so that the majority of its satellites are on its near side with respect to our line-of-sight. We quantify this result and find it to be significant at the ~3 sigma level. Until such time as a satisfactory explanation for this finding is presented, our results warn against treating the M31 subgroup as complete, unbiased and relaxed.

Alan McConnachie; Mike Irwin
2005-10-21

167

The ASCA satellite The JapaneseUS Xray observatory ASCA (Advanced Satellite for Cosmology and Astro

  Physics Websites

Summary: Chapter 2 The ASCA satellite The Japanese­US X­ray observatory ASCA (Advanced Satellite. ASCA was the first X­ray observatory with imaging capability through the hard X­ray band (up to 10 keV) and o#ered a combination of sensitivity and spectral resolution that was unprecedented. ASCA carried

Gelbord, Jonathan

168

Proposed Nomenclature for Surface Features on Pluto and Its Satellites and Names for Newly Discovered Satellites

  CERN Preprints

Summary: In anticipation of the July 2015 flyby of the Pluto system by NASA's New Horizons mission, we propose naming conventions and example names for surface features on Pluto and its satellites (Charon, Nix, Hydra, Kerberos, Styx) and names for newly discovered satellites.

Mamajek, Eric E; Cameron, David A; Olmedo, Manuel; Fogerty, Shane; Franklin, Eric; Lambrides, Erini; Hasan, Imran; Sarkis, Richard E; Thorndike, Stephen; Nordhaus, Jason
2015-01-01

169

6Name ________________________________ Satellite technology is everywhere! Right now, there are over 1587 working satellites orbiting

  Geosciences Websites

Summary: , there are over 1587 working satellites orbiting Earth. They represent over $160 billion in assets to the world years as new services are created, and better technology is developed. Satellites in the lowest orbits, called Low Earth Orbit (LEO) orbit between 300 to 1000 kilometers above the ground. Because Earth


170

Black rain: The burial of the Galilean satellites in irregular satellite debris William F. Bottke a,

  Physics Websites

Summary: Keywords: Ganymede Jupiter, Satellites Irregular satellites Callisto Europa a b s t r a c t Irregular, enough to grind themselves down to their current low-mass states. Here we explore the fate by Callisto, with a factor of 3­4 and 20­30 fewer particles reaching Ganymede and Europa/Io, respectively

Bottke, William F.

171

Reionization and the abundance of galactic satellites

  Astrophysics (arXiv)

Summary: One of the main challenges facing standard hierarchical structure formation models is that the predicted abundance of galactic subhalos with circular velocities of 10-30 km/s is an order of magnitude higher than the number of satellites actually observed within the Local Group. Using a simple model for the formation and evolution of dark halos, based on the extended Press-Schechter formalism and tested against N-body results, we show that the theoretical predictions can be reconciled with observations if gas accretion in low-mass halos is suppressed after the epoch of reionization. In this picture, the observed dwarf satellites correspond to the small fraction of halos that accreted substantial amounts of gas before reionization. The photoionization mechanism naturally explains why the discrepancy between predicted halos and observed satellites sets in at about 30 km/s, and for reasonable choices of the reionization redshift (z_re = 5-12) the model can reproduce both the amplitude and shape of the observed velocity function of galactic satellites. If this explanation is correct, then typical bright galaxy halos contain many low-mass dark matter subhalos. These might be detectable through their gravitational lensing effects, through their influence on stellar disks, or as dwarf satellites with very high mass-to-light ratios. This model also predicts a diffuse stellar component produced by large numbers of tidally disrupted dwarfs, perhaps sufficient to account for most of the Milky Way's stellar halo.

James S. Bullock; Andrey V. Kravtsov; David H. Weinberg
2000-02-09

172

Notes on the Missing Satellites Problem

  CERN Preprints

Summary: The Missing Satellites Problem (MSP) broadly refers to the overabundance of predicted Cold Dark Matter (CDM) subhalos compared to satellite galaxies known to exist in the Local Group. The most popular interpretation of the MSP is that the smallest dark matter halos in the universe are extremely inefficient at forming stars. The question from that standpoint is to identify the feedback source that makes small halos dark and to identify any obvious mass scale where the truncation in the efficiency of galaxy formation occurs. Among the most exciting developments in near-field cosmology in recent years is the discovery of a new population satellite galaxies orbiting the Milky Way and M31. Wide field, resolved star surveys have more than doubled the dwarf satellite count in less than a decade, revealing a population of ultrafaint galaxies that are less luminous that some star clusters. For the first time, there are empirical reasons to believe that there really are missing satellite galaxies in the Local Group, lu...

Bullock, James S
2010-01-01

173

Macho Parallaxes From A Single Satellite

  Astrophysics (arXiv)

Summary: Massive Compact Objects (Machos) are currently being discovered at substantially higher rates than would be expected from standard models of known stellar populations. To determine whether they are due to non-standard distri- butions of known populations or to a heretofore unknown (`dark') population, one must acquire more information about the individual events. Space-based parallaxes are potentially the best tool for extracting additional information. To leading order, parallax measurements by a single satellite result in a four- fold degeneracy: two possible values of $\\tilde v$ and two possible signs for the component of motion perpendicular to the projected satellite-Earth vector. It had been believed that a second satellite would be required to break this degeneracy. I show that the velocity difference between the satellite and the Earth allows one to partially or totally break the degeneracy using a single satellite. For most Macho events it is possible to measure $\\tilde v$ and $\\tilde r_e$. For some it is also possible to measure $\\Phi$. The proposed Space Infrared Telescope could measure $\\sim 100$ parallaxes per year by applying $\\sim 400\\,$hr of telescope time.

Andrew Gould
1994-08-10

174

The satellite distribution of M31

  CERN Preprints

Summary: (Abridged) The spatial distribution of the Galactic satellite system plays an important role in Galactic dynamics and cosmology, where its successful reproduction is a key test of simulations of galaxy halo formation. Here, we examine its representative nature by conducting an analysis of the 3-dimensional spatial distribution of the M31 subgroup of galaxies. We begin by a discussion of distance estimates and incompleteness concerns, before revisiting the question of membership of the M31 subgroup. Comparison of the distribution of M31 and Galactic satellites relative to the galactic disks suggests that the Galactic system is probably modestly incomplete at low latitudes by ~20%. We find that the radial distribution of satellites around M31 is more extended than the Galactic subgroup; 50% of the Galactic satellites are found within ~100kpc of the Galaxy, compared to ~200kpc for M31. We search for ``ghostly streams'' of satellites around M31, in the same way others have done for the Galaxy, and find several. T...

Irwin, A M C M
2006-01-01

175

On the Secular Behavior of Irregular Satellites

  Astrophysics (arXiv)

Summary: Although analytical studies on the secular motion of the irregular satellites have been published recently, these theories have not yet been satisfactorily reconciled with the results of direct numerical integrations. These discrepancies occur because in secular theories the disturbing function is averaged over orbital motions, whereas instead one should take into account some large periodic terms, most notably the so-called ``evection''. We demonstrate that such terms can be incorporated into the Kozai formalism, and that our synthetic approach produces much better agreement with results from symplectic integrations. Using this method, we plot the locations of secular resonances in the orbital-element space, and we note that the distribution of irregular satellite clusters appears to be non-random. We find that the large majority of irregular-satellite groups cluster close to the secular resonances, with several objects having practically stationary pericenters. None of the largest satellites belong to this class, so we argue that this dichotomy implies that the smaller near-resonant satellites might have been captured differently than the largest irregulars.

Matija Cuk; Joseph A. Burns
2004-08-05

176

Star Formation and Quenching of Satellite Galaxies

  CERN Preprints

Summary: We study the quenching of satellite galaxies by gradual depletion of gas due to star formation, by ram-pressure striping and by tidally triggered starburst. Using progenitors constrained by the empirical model of Lu et al., in which outflow loading factor is low, we do not find an over-quenching problem in satellites even if there is no further cold gas supply from the cooling of the halo gas after a galaxy is accreted by its host. Gradual depletion alone predicts a unimodal distribution in specific star formation, in contrast to the bimodal distribution observed, and under-predicts the quenched fraction in low mass halos. Ram-pressure stripping nicely reproduces the bimodal distribution but under-predicts the quenched fraction in low-mass halos. Starbursts in gas-rich satellites triggered by tidal interactions with central galaxies can nicely reproduce the quenched satellite population in low-mass halos, but become unimportant for low-mass satellites in massive halos. The combined processes, together with th...

Lu, Zhankui
2015-01-01

177

Massive Satellites of Close-In Gas Giant Exoplanets

  CERN Preprints

Summary: We study the orbits, tidal heating and mass loss from satellites around close-in gas giant exoplanets. The focus is on large satellites which are potentially observable by their transit signature. We argue that even Earth-size satellites around hot Jupiters may be immune to destruction by orbital decay; detection of such a massive satellite would strongly constrain theories of tidal dissipation in gas giants, in a manner complementary to orbital circularization. The star's gravity induces significant periodic eccentricity in the satellite's orbit. The resulting tidal heating rates, per unit mass, are far in excess of Io's and dominate radioactive heating out to planet orbital periods of months for reasonable satellite tidal $Q$. Inside planet orbital periods of about a week, tidal heating can completely melt the satellite. Lastly, we compute an upper limit to the satellite mass loss rate due to thermal evaporation from the surface, valid if the satellite's atmosphere is thin and vapor pressure is negligible. ...

Cassidy, Timothy A; Arras, Phil; Johnson, Robert E; Skrutskie, Michael F
2009-01-01

178

Modeling the Milky-Way Satellite galaxies

  Astrophysics (arXiv)

Summary: We revisit the Milky Way satellite problem using a semi-analytical model of galaxy formation and compare the predicted luminosity function to recent result from the SDSS. With cosmic photoionization, the luminosity function can be brought into broad agreement with the data between $-15< M_{V} <-2$. This improvement over previous semi-analytical model results (e.g., Benson et al.2002) is from our adoption of improved models for galaxy merger history and galaxy merging time-scales. The very faint satellites ($M_{v} > -5$) formed in halos with virial temperature over $10^{4}K$ (mass around $10^{9} M_{\\odot}$ before accretion), but their baryon content are strongly suppressed by photoionization. We model the mass evolution of the subhalos, and compare the predicted mass-to-light ratio with the data. We find that the measured total mass inside the luminous radii of satellites are about 5% of their present total dark matter mass.

X. Kang
2008-06-19

179

Introducing Relativity in Global Navigation Satellite Systems

  General Relativity & Quantum Cosmology (arXiv)

Summary: Today, the Global Navigation Satellite Systems, used as global positioning systems, are the GPS and the GLONASS. They are based on a Newtonian model and hence they are only operative when several relativistic effects are taken into account. The most important relativistic effects (to order 1/c^2) are: the Einstein gravitational blue shift effect of the satellite clock frequency (Equivalence Principle of General Relativity) and the Doppler red shift of second order, due to the motion of the satellite (Special Relativity). On the other hand, in a few years the Galileo system will be built, copying the GPS system unless an alternative project is designed. In this work, it will be also shown that the SYPOR project, using fully relativistic concepts, is an alternative to a mere copy of the GPS system. According to this project, the Galileo system would be exact and there would be no need for relativistic corrections.

J. -F. Pascual-Sanchez
2006-12-13

180

On Asymmetric Distributions of Satellite Galaxies

  CERN Preprints

Summary: We demonstrate that the asymmetric distribution of M31 satellites cannot be produced by tides from the Milky Way as such effects are too weak. However, loosely bound associations and groups of satellites can fall into larger haloes and give rise to asymmetries. We compute the survival times for such associations. We prove that the survival time is always shortest in Keplerian potentials, and can be ~ 3 times longer in logarithmic potentials. We provide an analytical formula for the dispersal time in terms of the size and velocity dispersion of the infalling structure. We show that, if an association of ~10 dwarfs fell into the M31 halo, its present aspect would be that of an asymmetric disk of satellites. We also discuss the case of cold substructure in the Andromeda II and Ursa Minor dwarfs.

Bowden, A; Belokurov, V
2014-01-01

181

Dwarf satellite galaxies in the modified dynamics

  Astrophysics (arXiv)

Summary: In the modified dynamics (MOND) the inner workings of dwarf satellites can be greatly affected by their mother galaxy-over and beyond its tidal effects. Because of MOND's nonlinearity a system's internal dynamics can be altered by an external field in which it is immersed (even when this field, by itself, is constant in space). As a result, the size and velocity dispersion of the satellite vary as the external field varies along its orbit. A notable outcome of this is a substantial increase in the dwarf's vulnerability to eventual tidal disruption-rather higher than Newtonian dynamics (with a dark-matter halo) would lead us to expect for a satellite with given observed parameters.

Rafael Brada; Mordehai Milgrom
2000-05-11

182

The morphological evolution of galaxy satellites

  Astrophysics (arXiv)

Summary: We study the evolution of galaxy satellites with high resolution N-body simulations. Satellites are modeled as replicas of typical low and high surface brightness galaxies (LSBs and HSBs). Encounters on high eccentricity orbits (as typical in hierarchical models of galaxy formation) strip LSBs of most of their stars and tend to decrease their surface brightness. On the contrary, bar instability in HSBs leads to substantial loss of angular momentum of the stellar component and to an increase of central surface brightness. In both cases the remnant resembles a spheroidal galaxy with an exponential surface brightness profile. A simple modeling of color evolution and interactions driven star formation gives M/L ratios for the remnants that are roughly consistent with observations. These results suggest an evolutionary scenario for the dwarf galaxies in our Local Group, faint dSphs being the descendents of LSBs and brighter dSphs/dEs being the final state of HSB satellites.

Lucio Mayer; Fabio Governato; Monica Colpi; Ben Moore; Thomas R. Quinn; Carlton M. Baugh
1999-03-30

183

Satellite Systems around Galaxies in Hydrodynamic Simulations

  Astrophysics (arXiv)

Summary: We investigate the properties of satellite galaxies formed in N-body/SPH simulations of galaxy formation in the $\\Lambda$CDM cosmology. The simulations include the main physical effects thought to be important in galaxy formation and, in several cases, produce realistic spiral discs. In total, a sample of 9 galaxies of luminosity comparable to the Milky Way was obtained. At magnitudes brighter than the resolution limit, $M_V=-12$, the luminosity function of the satellite galaxies in the simulations is in excellent agreement with data for the Local Group. The radial number density profile of the model satellites, as well as their gas fractions also match observations very well. In agreement with previous N-body studies, we find that the satellites tend to be distributed in highly flattened configurations whose major axis is aligned with the major axis of the (generally triaxial) dark halo. In 2 out of 3 systems with sufficiently large satellite populations, the satellite system is nearly perpendicular to the plane of the galactic disc, a configuration analogous to that observed in the Milk Way. The discs themselves are perpendicular to the minor axis of their host halos in the inner parts, and the correlation between the orientation of the galaxy and the shape of the halo persists even out to the virial radius. However, in one case the disc's minor axis ends up, at the virial radius, perpendicular to the minor axis of the halo. The angular momenta of the galaxies and their host halo tend to be well aligned.

Noam I Libeskind; Shaun Cole; Carlos S Frenk; Takashi Okamoto; Adrian Jenkins
2006-07-11

184

Internal waves and vortices in satellite images

  CERN Preprints

Summary: Some recent papers proposed the use of the satellite images of Google Earth in teaching physics, in particular to see some behaviours of waves. Reflection, refraction, diffraction and interference are easy to be found in these satellite maps. Besides Google Earth, other sites exist, such as Earth Observatory or Earth Snapshot, suitable for illustrating the large-scale phenomena in atmosphere and oceans In this paper, we will see some examples for teaching surface and internal sea waves, and internal waves and the K\\'arm\\'an vortices in the atmosphere. Aim of this proposal is attracting the interest of students of engineering schools to the physics of waves.

Sparavigna, Amelia Carolina
2012-01-01

185

A relativistic and autonomous navigation satellite system

  CERN Preprints

Summary: A relativistic positioning system has been proposed by Bartolom\\'e Coll in 2002. Since then, several group developed this topic with different approaches. I will present a work done in collaboration with Ljubljana University and the ESA Advanced Concepts Team. We developed a concept, Autonomous Basis of Coordinates, in order to take advantage of the full autonomy of a satellite constellation for navigation and positioning, by means of satellite inter-links. I will present the advantages of this new paradigm and a number of potential application for reference systems, geophysics and relativistic gravitation.

Delva, Pacôme; Kosti?, Uros; Carloni, Sante
2011-01-01

186

A relativistic and autonomous navigation satellite system

  General Relativity & Quantum Cosmology (arXiv)

Summary: A relativistic positioning system has been proposed by Bartolom\\'e Coll in 2002. Since then, several group developed this topic with different approaches. I will present a work done in collaboration with Ljubljana University and the ESA Advanced Concepts Team. We developed a concept, Autonomous Basis of Coordinates, in order to take advantage of the full autonomy of a satellite constellation for navigation and positioning, by means of satellite inter-links. I will present the advantages of this new paradigm and a number of potential application for reference systems, geophysics and relativistic gravitation.

Pacôme Delva; Andrej Cadez; Uros Kostic; Sante Carloni
2011-06-17

187

On the orbit of the LARES satellite

  General Relativity & Quantum Cosmology (arXiv)

Summary: This paper is motivated by the recent possibility to find an inexpensive launching vehicle for the LARES satellite, however at an altitude much lower than originally planned for the LAGEOS III/LARES satellite. We present here a preliminary error analysis corresponding to a lower, quasi-polar, orbit, in particular we analyze the effect on the LARES node of the Earth's static gravitational field, and in particular of the Earth's even zonal harmonics, the effect of the time dependent Earth's gravitational field, and in particular of the K1 tide, and the effect of particle drag.

Ignazio Ciufolini
2006-09-20

188

CLARKSON UNIVERSITY Oceanographic Modeling with Hyperspectral Satellite Imagery

  Mathematics Websites

Summary: Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.7 Hyperspectral ImagersCLARKSON UNIVERSITY Oceanographic Modeling with Hyperspectral Satellite Imagery A Dissertation with Hyperspectral Satellite Imagery" presented by Sean Jason Kramer, a candidate for the degree of Doctor

Bollt, Erik

189

Research Article Satellite Attitude Control Using Analytical Solutions to

  Engineering Websites

Summary: Research Article Satellite Attitude Control Using Analytical Solutions to Approximations method is applied to the problem of satellite attitude control with attitude parameterization-Jacobi equation and the controller dynamics. 1. Introduction The attitude control problem is critical for most

Damaren, Christopher J.

190

Lattice Formation in Space for a Swarm of Pico Satellites

  Computer Technologies and Information Sciences Websites

Summary: , coordinated observation [1,2], autonomous self-assembly of solar powered satellites [3], large antennas a regular hexagonal lattice located on the xy plane (see Figure 1). The satellites keep a mutual target

Libre de Bruxelles, Université

191

INSURED project (INtegrated Satellite UMTS Real Environment Demonstrator)

  Engineering Websites

Summary: satellite system (IRIDIUM) and a GSM network. The trials carried out with the demonstrator are of paramount; the first pre-operational IRIDIUM satellites are available for experimentation. The INSURED project

Vouyioukas, Demosthenes

192

Satellite Observations of Tropospheric Chemistry: Retrievals and Interpretation

  Geosciences Websites

Summary: Satellite Observations of Tropospheric Chemistry: Retrievals and Interpretation A thesis presented;Daniel J. Jacob Randall V. Martin Satellite Observations of Tropospheric Chemistry: Retrievals and Interpretation Abstract This thesis exploits nascent capabilities for observation of tropospheric chemistry from

Martin, Randall

193

he Transportable Satellite Internet System (TSIS), a combined research

  Computer Technologies and Information Sciences Websites

Summary: and satellite technology, radio frequency, Internet and telecommunications research. For the complete storyT he Transportable Satellite Internet System (TSIS), a combined research effort between OARnet Award Columbus is once again the "Internet Crossroads" for international telecommunications

Calyam, Prasad

194

Satellite-derived vertical dependence of tropical tropospheric temperature trends

  Engineering Websites

Summary: Satellite-derived vertical dependence of tropical tropospheric temperature trends Qiang Fu] Tropical atmospheric temperatures in different tropospheric layers are retrieved using satellite-borne Microwave Sounding Unit (MSU) observations. We find that tropospheric temperature trends in the tropics

Hochberg, Michael

195

Discretized Constrained Attitude Pathfinding and Control for Satellites

  Engineering Websites

Summary: Discretized Constrained Attitude Pathfinding and Control for Satellites Henri C. Kjellberg and E guidance, navigation, and control algorithm is developed for satellites with three degree-of- freedom rotation maneuverability. The algorithm is capable of meeting multiple pointing constraints autonomously

Lightsey, Glenn

196

Achieving broad access to satellite control research with zero robotics

  MIT - DSpace

Summary: Since operations began in 2006, the SPHERES facility, including three satellites aboard the International Space Station (ISS), has demonstrated many future satellite technologies in a true microgravity environment and ...

Katz, Jacob G
2013-01-01

197

Building technological capability within satellite programs in developing countries

  MIT - DSpace

Summary: Global participation in space activity is growing as satellite technology matures and spreads. Countries in Africa, Asia and Latin America are creating or reinvigorating national satellite programs. These countries are ...

Wood, Danielle Renee
2012-01-01

198

STABILITY OF SATELLITES IN CLOSELY PACKED PLANETARY SYSTEMS

  MIT - DSpace

Summary: We perform numerical integrations of four-body (star, planet, planet, satellite) systems to investigate the stability of satellites in planetary systems with tightly packed inner planets (STIPs). We find that the majority ...

Payne, Matthew J.

199

NHC SATELLITE IMAGERY DATA FEED Full disk: every 3 hours

  Geosciences Websites

Summary: NHC SATELLITE IMAGERY DATA FEED SATELLITE GOES-E FORMAT McIDAS FREQUENCY Full disk: every 3 hours N Kerenel 400 GB Ultra SCSI RAID Storage 4 GB Memory Dual Port Ultra 2 SCSI Adapter PCIFWDSCSI2 Card 1000


200

Assesment and Prediction of Natural Hazards from Satellite Imagery

  University of California eScholarship Repository

Summary: based ?ood vulnerability assessment of human settlements: aassessment and high-resolution predictive maps of flood vulnerabilityAssessment and prediction of natural hazards from satellite imagery 463 explored the potential utility of satellite images to determine the vulnerability

Gillespie, Thomas; Chu, Jasmine; Frankenberg, Elizabeth; Thomas, Duncan
2007-01-01

201

MICHAELMATSON NOAA National Earth Satellite Service

  Environmental Sciences and Ecology Websites

Summary: Sources Using a Thermal IR Sensor Steel mills, and gas flares from oil fields, were identified by using the 3.8-pm and 11-pm sensors on board the NOAA-6 satellite. INTRODUCTION THE THIRD. Examples resented include gas flares from oil fields in the Middle East and steel mills in the midwestern

Dozier, Jeff

202

The chemical composition of the Galileian satellites

  Astrophysics (arXiv)

Summary: Using the semiclassical theory of dense matter proposed by P.Savic and R.Kasanin,the mean molecular masses of the Galilean satellites of Jupiter are determined.The calculated values are fitted by plausible combinations of chemical elements,and the results are in good agreement with the observations by "Galileo".Possible cosmogonical explanations are briefly discussed.

V. Celebonovic
1998-07-20

203

Satellite Tagging and Cardiac Physiology Reveal Niche

  Geosciences Websites

Summary: to track salmon sharks (Lamna ditropis) for up to 3.2 years. Here we show that salmon sharks have strat- egies. Sharks have been tracked using short- term acoustic telemetry (2) and towed satellite tags tags (PATs) have also been used to track sharks (5, 6); however, geolocations have root mean square

Luther, Douglas S.

204

Introduction satellite based scatterometers provide high

  Geosciences Websites

Summary: 30 Introduction satellite based scatterometers provide high resolution all-weather wind vector fields over the seas. Wind speed and wind direction are provided at high accuracy under all weather for the forecasting of fast developing and severe weather. Moreover, scatterometer wind fields are provided

Haak, Hein

205

Satellite Navigation in Vietnam & The NAVIS Centre

  Engineering Websites

Summary: Satellite Navigation in Vietnam & The NAVIS Centre TA HAI TUNG (PhD) NAVIS Centre, HUST, Vietnam GNSS Futures UNSW, Sydney, Australia, 7-8 July 2014 #12;Space Technology in Vietnam · 2006: the PM adopted the "STRATEGY FOR SPACE RESEARCH & APPLICATIONS

Sekercioglu, Y. Ahmet

206

Ocean Surface Currents From Geostationary Satellite SST

  Geosciences Websites

Summary: Ocean Surface Currents From Geostationary Satellite SST -We are implementing and evaluating a feature tracking approach to estimate ocean surface currents. - This approach allows us to estimate in the global ocean where images are available. Uses include search and rescue, monitoring trajectories

Kurapov, Alexander

207

HORSESHOE PERIODIC ORBITS FOR SATURN COORBITAL SATELLITES

  Mathematics Websites

Summary: HORSESHOE PERIODIC ORBITS FOR SATURN COORBITAL SATELLITES Jaume Llibre and Merc`e Oll'e Dept. Matem conclude that there exist stable horseshoe periodic orbits which fit with the motion of Saturn coorbital­ stricted problem. 1. Introduction In 1981 the successful Voyager flights to Saturn confirmed the existence

Politècnica de Catalunya, Universitat

208

Eavesdropping on Satellite Telecommunication Benedikt Driessen

  Mathematics Websites

Summary: for the public to openly discuss and un- derstand closed-source systems. Historically, GSM relied on a setEavesdropping on Satellite Telecommunication Systems draft Benedikt Driessen Horst-Goertz Institute of "digital realm" captures virtually everything from "classic" telecommunication technol- ogy (e.g., GSM


209

Satellite Transport Protocol Handling Bit Corruption,

  Computer Technologies and Information Sciences Websites

Summary: Satellite Transport Protocol Handling Bit Corruption, Handoff and Limited Connectivity MAGED E networks have a unique set of link errors including bit corruption, handoff, and limited connectivity networks. This inability to handle multiple kinds of errors results in severe degradation in effective

Barbeau, Michel

210

The Aerospace Corporation 2009 Communication Satellite Systems

  Computer Technologies and Information Sciences Websites

Summary: : ­ Communication Satellites, fifth edition, by D. Martin, P. Anderson, L. Bartamian, Aerospace / AIAA Press, 2006 ­ Propagation Impairments (e.g. rain fade, shadowing, multipath) #12;4 Dimensions (1) · Operator types) ­ Global #12;5 Dimensions (2) · Regulatory (spectrum management) ­ National licensing, coordination · FCC

Low, Steven H.

211

Satellite atmospheres Melissa A. McGrath

  Physics Websites

Summary: ). At the time of that book, only one of these satellites, Io, was thought to possess an atmosphere, although al. 1973). The discovery of the Io plasma torus (Kupo et al. 1976) and the in situ characterization (sodium and potassium) were known to be present on Io, today nine atomic and molecular species have been

Johnson, Robert E.

212

Signal Authentication in Trusted Satellite Navigation Receivers

  Computer Technologies and Information Sciences Websites

Summary: -spoof measures, location- based service 1 Introduction Physical location can be an important security parameter/Compass, . . . ). Each of these operates a constellation of Earth-orbiting satellites that broadcast a high-precision time signal, along with a low-bitrate data stream (50­1000 bit/s) that carries orbital

Kuhn, Markus

213

Using Satellite Imagery to Detect Illegal Logging

  Renewable Energy Websites

Summary: for Compliance Monitoring #12;Limitations and Benefits of Compliance Monitoring by Remote Sensing Limitations.globalforestwatch.org/english/about/illeglog/illeglog_workshop_presentations.htm #12;GFW Remote Sensing Work on Illegal Logging · Cameroon ­ pilot dataset completed · Central Africa (proposed) · Indonesia (partial funding) #12;Why use satellite imagery to monitor logging roads? · Imagery


214

Total Solar Irradiance Satellite Composites and their

  Mathematics Websites

Summary: Chapter 12 Total Solar Irradiance Satellite Composites and their Phenomenological Effect on Climate. Phenomenological solar signature on climate 310 9. Conclusion 312 1. INTRODUCTION A contiguoustotal solar from each other, in particular about whether the TSI minimum during solar Cycles 22e23 (1995

Scafetta, Nicola

215

SEMI EMPIRICAL SATELLITE MODELS Richard Perez1

  Renewable Energy Websites

Summary: University of New York, ASRC, Albany, NY, USA 2 GeoModel Solar, Bratislava, Slovakia Abstract This chapter discusses basic principles of solar irradiance modeling based on the use of input data from geostationary satellites and atmospheric models. Two operational approaches (SUNY/SolarAnywhere and SolarGIS) based

Perez, Richard R.

216

Hom y Skein Theory Reversed String Satellites

  Mathematics Websites

Summary: with the requirements of the University of Liverpool for the degree of Doctor in Philosophy by Richard John Hadji December 2003 #12; Richard John Hadji Hom y Skein Theory of Reversed String Satellites Abstract This thesis for their support; Mum, Dad, Louise and Gemma. Finally, a very special thank you to Carol, your love is everything

Morton, Hugh

217

Introduction satellite observations of atmospheric constitents have

  Geosciences Websites

Summary: observations satellite instruments (such as GOME, sCIAMAChY and OMI) use spectroscopy to retrieve atmospheric 1995 with GOME, since 2002 with sCIAMAChY, and since 2004 with the OMI instrument; the latter two as measured by OMI in the period May 2006 till February 2007. Clearly visible are the industrial regions

Haak, Hein

218

Test problems for quasi-satellite packing????

  Optimization Online

Summary: applications such as spacecraft, car, ship, machining center, shield machine and ... However, algorithm theory analysis (such as the complexity analysis and the .... errors. (xc, yc, zc)is the expected centroid position of the satellite system, ..... successfully finds the optimum over the total number Nc of times that the algorithm is.

Administrator
2008-10-14

219

The surprising inefficiency of dwarf satellite quenching

  CERN Preprints

Summary: We study dwarf satellite galaxy quenching using observations from the Geha et al. (2012) NSA/SDSS catalog together with LCDM cosmological simulations to facilitate selection and interpretation. We show that fewer than 30% of dwarfs (M* ~ 10^8.5-10^9.5 Msun) identified as satellites within massive host halos (Mhost ~ 10^12.5-10^14 Msun) are quenched, in spite of the expectation from simulations that half of them should have been accreted more than 6 Gyr ago. We conclude that whatever the action triggering environmental quenching of dwarf satellites, the process must be highly inefficient. We investigate a series of simple, one-parameter quenching models in order understand what is required to explain the low quenched fraction and conclude that either the quenching timescale is very long (> 9.5 Gyr, a "slow starvation" scenario) or that the environmental trigger is not well matched to accretion within the virial volume. We discuss these results in light of the fact that most of the low mass dwarf satellites in ...

Wheeler, Coral; Cooper, Michael C; Boylan-Kolchin, Mike; Bullock, James S
2014-01-01

220

Asymmetric Warfare: M31 and its Satellites

  CERN Preprints

Summary: Photometric surveys of M31's halo vividly illustrate the wreckage caused by hierarchical galaxy formation. Several of M31's satellites are being disrupted by M31's tidal field, among them M33 and And I, while other tidal structures are the corpses of satellites already destroyed. The extent to which M31's satellites have left battle scars upon it is unknown; to answer this we need accurate orbits and masses of the perturbers. I focus here on M31's 150-kpc-long Giant Southern Stream (GSS) as an example of how these can be determined even in the absence of a visible progenitor. Comparing N-body models to photometric and spectroscopic data, I find this stream resulted from the disruption of a large satellite galaxy by a close passage about 750 Myr ago. The GSS is connected to several other debris structures in M31's halo. Bayesian sampling of the simulations estimates the progenitor's initial mass as log(Mstar/Msun) = 9.5 +- 0.2, showing it was one of the most massive Local Group galaxies until quite recently. T...

Fardal, Mark A
2009-01-01

221

DISASTER RECOVERY APPLICATIONS FOR SATELLITE COMMUNICATIONS SYSTEMS

  Engineering Websites

Summary: Young, Chris Washburn J. Warren McClure School of Communication Systems Management Don Flournoy School management systems. We suggest opportunities for closer ties between the network management systemDISASTER RECOVERY APPLICATIONS FOR SATELLITE COMMUNICATIONS SYSTEMS Hans Kruse, Tony Mele, Sara

Kruse, Hans

222

Isolated Galaxies and Isolated Satellite Systems

  CERN Preprints

Summary: We search for isolated galaxies using a volume-limited sample of galaxies with 0.02r_{vir,nei} and \\rho <\\bar{\\rho} well segregates the CIG galaxies. We confirm the morphology conformity between the host and their satellites, which suggests importance of hydrodynamic interaction among galaxies within their virial radii in galaxy evolution.

Ann, H B; Choi, Yun-Young
2009-01-01

223

ATS 351, Spring 2010 Satellite 50 points

  Geosciences Websites

Summary: their own radiation, and measure the return signal that is sent back to them. A good example of an active sensor is a radar. Passive sensors do not emit any radiation, and only detect naturally occurring radiation that is emitted. Most satellites are passive sensors. 3. (5 points). Label each of the following

Rutledge, Steven

224

Driving Innovation A Satellite Applications TIC

  Physics Websites

Summary: Projects #12;Driving Innovation SatApps TIC - goal `generating growth across the economy through new;Driving Innovation What does industry need from the SatApps TIC ? · Risk reduction ­ Prove that new Data Downlink & Processing Data Exploitation & Application Satellite Operations SatApps TIC aims


225

Transient Astronomy with the Gaia Satellite

  Physics Websites

Summary: Transient Astronomy with the Gaia Satellite Simon Hodgkin, Lukasz Wyrzykowski, Ross Burgon, Sergey Institute of Astronomy, Cambridge #12;New windows on transients across the universe, April 23-24 2012, Royal windows on transients across the universe, April 23-24 2012, Royal SocietySimon Hodgkin, IoA, Cambridge

Hinton, Jim

226

Dynamics and real-time optimal control of satellite attitude and satellite formation systems

  Texas A&M University - TxSpace

Summary: . Three-axis magnetic attitude stabilization is achieved by using a pseudospectral control law via the receding horizon control for satellites in eccentric low Earth orbits. The solutions from the pseudospectral control law are in excellent agreement...

Yan, Hui
2006-10-30

227

Analysis of Low Earth Orbit Satellite Networks with Inter-satellite Links

  Computer Technologies and Information Sciences Websites

Summary: to the network architect to choose among several competing designs for the crosslink architecture and gives the one with a high ow number. We show that the ow number of a a hexagonal satellite constellation

Sen, Arunabha

228

On stacked central configuration of the planar coorbital satellites problem

  CERN Preprints

Summary: In this work we look for central configurations of the planar 1 + n body problem such that, after the addition of one or two satellites, we have a new planar central configuration. We determine all such configurations in two cases: the first, the addition of two satellites considering that all satellites have equal infinitesimal masses and the second case where one satellite is added but the infinitesimal masses are not necessarily equal.

Oliveira, Allyson
2011-01-01

229

Cognitive Satellite Terrestrial Radios Sithamparanathan Kandeepan, Luca De Nardis, Maria-Gabriella Di Benedetto,

  Engineering Websites

Summary: Cognitive Satellite Terrestrial Radios § Sithamparanathan Kandeepan, Luca De Nardis, Maria the concept of cognitive satellite terrestrial radios (CSTR) for hybrid satellite-terrestrial systems (HSTS of the radio spectrum. The future satellite ground terminals therefore need to integrate and co

Di Benedetto, Maria-Gabriella

230

Programmable Active Networking supporting Next Generation Multimedia Services in Satellite Networks

  Computer Technologies and Information Sciences Websites

Summary: 1 Programmable Active Networking supporting Next Generation Multimedia Services in Satellite the space segment of satellite networks could take benefit. The first commercial regenerative satellite routing functionality will become available. However, from the design of these satellite systems

Bhatti, Saleem N.

231

Ris-R-1479(EN) Satellite information for wind energy

  Multidisciplinary Databases and Resources Websites

Summary: Risø-R-1479(EN) Satellite information for wind energy applications Morten Nielsen, Poul Astrup Title: Satellite information for wind energy applications Department: Wind Energy Department Risø-R-1479.): An introduction to satellite information relevant for wind energy applications is given. It includes digital


232

Modelling Uncertainty in Satellite Derived Land Edward Cripps

  Mathematics Websites

Summary: Modelling Uncertainty in Satellite Derived Land Cover Maps Edward Cripps Anthony O'Hagan Tristan associated with land cover maps derived from satellite data. Satellites record energy reflected from the earth's surface and this information may be used to derive maps of land cover. Typically these maps

Oakley, Jeremy

233

Rception des signaux AIS par satellite Raoul PRVOST

  Engineering Websites

Summary: organisé en cellules 29/09/2011 4/46 #12;Automatic Identification System · Bateaux à portée l'un de l orbite base : ~650 km. 29/09/2011 7/46 #12;Réception par satellite · Système AIS non adapté au satellite;Réception par satellite · Collisions entre les messages des différentes cellules · Utilisation de méthodes

Dobigeon, Nicolas

234

Adaptive Satellite Attitude Control in the Presence of

  Engineering Websites

Summary: Adaptive Satellite Attitude Control in the Presence of Inertia and CMG Gimbal Friction], the space industry is moving toward smaller satellites and the buses that support them. Some proposed uses of these small satellites (small- sats) include astrophysics research, surveillance, and autonomous servicing

Dixon, Warren

235

Segmentation of Occluded Sidewalks in Satellite Images Turgay Senlet1

  Computer Technologies and Information Sciences Websites

Summary: Segmentation of Occluded Sidewalks in Satellite Images Turgay Senlet1 and Ahmed Elgammal2 , elgammal@cs.rutgers.edu2 Abstract Accurate segmentation of sidewalks from satellite images can be required propose a framework to construct sidewalk and crosswalk maps from satellite images. This is a challenging

Elgammal, Ahmed

236

Parallelization of the Naval Space Surveillance Satellite Motion Model

  Mathematics Websites

Summary: Parallelization of the Naval Space Surveillance Satellite Motion Model Warren E. Phipps Jr. Beny (NAVSPASUR) uses an analytic satellite motion model based on the Brouwer - Lyddane theory to track objects-node hypercube. Introduction The Naval Space SurveillanceCenter (NAVSPASUR) uses an analytic satellite

Danielson, Don

237

Decision Making Based on Satellite Images: Optimal Fuzzy Clustering Approach

  Computer Technologies and Information Sciences Websites

Summary: Decision Making Based on Satellite Images: Optimal Fuzzy Clustering Approach Vladik Kreinovich 1, in processing satellite images, we have an enormous amount of information to process. To speed up the in and Formulation of the Problem For satellite imaging, fuzzy clustering is im­ portant. Decision making

Kreinovich, Vladik

238

Using the ARPS Satellite Data Remapper Keith Brewster

  Geosciences Websites

Summary: AREA file satellite data from the satellite-observed pixels to the ARPS grid. 2.Usage makearps mci2arps cp ./src/mci2arps/palgrey.hdf . mci2arps /directory/name_of_satellite_file .input to know what your ctrlat,ctrlon, nx,ny and dx,dy are. It uses the runname in the input file to construct

Droegemeier, Kelvin K.

239

On the Life and Death of Satellite Haloes

  CERN Preprints

Summary: We study the evolution of dark matter satellites orbiting inside more massive haloes using semi-analytical tools coupled with high-resolution N-Body simulations. We select initial satellite sizes, masses, orbital energies, and eccentricities as predicted by hierarchical models of structure formation. Both the satellite and the main halo are described by a Navarro, Frenk & White density profile with various concentrations.

Taffoni, G; Colpi, M; Governato, F; Taffoni, Giuliano; Mayer, Lucio; Colpi, Monica
2003-01-01

240

Analysis of billing data from a hybrid satellite network

  Engineering Websites

Summary: Data transfer pair for dialup, DSL, or cable modem is: source (user) IP, destination IP DirecPC data and television services: DirecTV: satellite television service DirecPC: unidirectional satellite data service DirecWay: bi-directional satellite data service replacing DirecPC #12;November 29, 2005

Trajkovic, Ljiljana

241

Aerosol Satellite Remote Sensing Satelliet Detectie van Aerosolen

  Geosciences Websites

Summary: #12;Aerosol Satellite Remote Sensing Satelliet Detectie van A¨erosolen (met een samenvatting in het possible by a grant from the Netherlands Space Research Organization (SRON). ISBN 90-393-2173-6 #12;Now . . . . . . . . . . . . . . . . . . . . . . . . 11 1.4 Aerosol Satellite Remote Sensing . . . . . . . . . . . . . . . . . . 11 1.5 Satellite Sensors

Haak, Hein

242

An abundant population of small irregular satellites around Jupiter

  Geosciences Websites

Summary: uncertain, the study of irregular satellites provides a window on processes operating in the young Solar a systematic survey designed to assess the properties of the Jupiter satellite population. Bound satellites radii) corre- sponding to a circle of radius 4.7 degrees in the plane of the sky, when viewed

Sheppard, Scott S.

243

Cognitive Vision for Autonomous Satellite Rendezvous and Docking

  Computer Technologies and Information Sciences Websites

Summary: exclusively on vision to estimate the pose of the satellite and can deal with an uncooperative satellite. 1Cognitive Vision for Autonomous Satellite Rendezvous and Docking Faisal Z. Qureshi and Demetri that com- bines low-level object recognition and tracking with high-level symbolic reasoning

Terzopoulos, Demetri

244

Channel Allocation Using Pricing in Satellite and Eytan Modiano

  Engineering Websites

Summary: rate for each user here is the rate at which each user can access the satellite network by sending its data to any satellite within its view. Slotted aloha is used here as the multi-access scheme for itsChannel Allocation Using Pricing in Satellite Networks Jun Sun1 and Eytan Modiano Laboratory

Modiano, Eytan

245

MODIS AND OMI SATELLITE OBSERVATIONS SUPPORTING AIR QUALITY MONITORING

  Environmental Sciences and Ecology Websites

Summary: -observing satellite sensors are combined here with regional meteorological and chemical transport models. Two, as simulated by MM5, to infer aerosol optical properties to PM projection coefficients. Daily maps of satellite- troradiometer (MODIS) sensors onboard NASA's Terra and Aqua satellite, and surface concentrations of PM2

Curci, Gabriele

246

On Reducing Temporal Aliasing with Multi-Satellite Formations Introduction

  Geosciences Websites

Summary: On Reducing Temporal Aliasing with Multi-Satellite Formations Introduction Temporal aliasing is one of the main restrictions of current and future satellite missions targeting for the temporal variations-to-Satellite tracking (SST) missions are sensitive for the hydrological and glaciological variations. These altitude

Stuttgart, Universität

247

KA-BROADBAND SATELLITE COMMUNICATION USING CYCLOSTATIONARY PARABOLIC BEAMFORMING

  Engineering Websites

Summary: KA-BROADBAND SATELLITE COMMUNICATION USING CYCLOSTATIONARY PARABOLIC BEAMFORMING by PAUL LUSINA of a broadband satellite system which operates at the Ka frequency band. A channel model was developed which indicated that the satellite link would be noise limited and slowly time varying. Cyclostationary

Blostein, Steven D.

248

On-Demand Routing in LEO Satellite Systems Stylianos Karapantazis

  Computer Technologies and Information Sciences Websites

Summary: On-Demand Routing in LEO Satellite Systems Stylianos Karapantazis Aristotle University) satellite systems is proposed and evaluated. This protocol can be viewed as a variant of the well-known ad by the characteristics of LEO satellite systems' topology. The LAOR protocol is assessed for different link-cost metrics

Papapetrou, Evaggelos

249

Control Theory Optimization of MECN in Satellite Networks Arjan Durresi

  Computer Technologies and Information Sciences Websites

Summary: Control Theory Optimization of MECN in Satellite Networks Arjan Durresi Louisiana State University many fold in Satellite networks, where the resources are very expensive. Thus congestion control has a special significance in the performance of Satellite networks. In today's Internet, congestion control

Jain, Raj

250

Postgrado en Investigacin Matemtica Knots, satellites and algebra

  Mathematics Websites

Summary: Curso Postgrado en Investigación Matemática Knots, satellites and algebra 20 - 24 de abril de 2009 with invariants of knots. Linking number of curves and use of Seifert surfaces. Construction of satellites. Its relation to other knot invariants and its use in conjunction with satellites. The defining skein

Tradacete, Pedro

251

Satellite Measurements of Trace Gases or Air Pollutants

  Geosciences Websites

Summary: Satellite Measurements of Trace Gases or Air Pollutants Orbits, measurement types, spectral regions, proper4es #12;Satellite monitoring of the changing world - daily #12;Satellite Orbits There are different types of orbits around the Earth of varying sizes and each

Dickerson, Russell R.

252

Introduction to satellite constellations orbital types, uses and related facts

  Engineering Websites

Summary: Introduction to satellite constellations orbital types, uses and related facts Dr Lloyd Wood space that satellite moves at same angular velocity as Earth's rotation, so appears still. (period: 1 sidereal day.) · Three satellites spaced equally around the Equator cover most of Earth ­ but not the poles. (Arthur C

Wood, Lloyd

253

The Anticoincidence System of the PAMELA Satellite Experiment

  Materials Science Websites

Summary: The Anticoincidence System of the PAMELA Satellite Experiment Design of the Data Acquisition System of the PAMELA Satellite Experiment - Design of the Data Acquisition System and Performance Studies Abstract PAMELA is a satellite-borne cosmic ray experiment. Its primary scientific objective is to study

Haviland, David

254

THE CROSSING NUMBER OF SATELLITE KNOTS MARC LACKENBY

  Mathematics Websites

Summary: THE CROSSING NUMBER OF SATELLITE KNOTS MARC LACKENBY 1. Introduction One of the most basic are particular cases of satellite knots, which are defined as follows. Let L be a non-trivial knot in the 3-sphere. Then a knot K is a satellite knot with companion knot L if K lies in a regular neighbourhood N

Lackenby, Marc

255

KEY MANAGEMENT FOR SECURE MULTICAST IN HYBRID SATELLITE NETWORKS

  Engineering Websites

Summary: KEY MANAGEMENT FOR SECURE MULTICAST IN HYBRID SATELLITE NETWORKS Ayan Roy-Chowdhury Department This paper proposes a design for key management for secure multicast in hy- brid satellite networks. Communication satellites offer an efficient way to ex- tend IP multicast services for groups in wide

Baras, John S.

256

2014 AADR Satellite Symposium in Clinical Research Charlotte, North Carolina

  Biology and Medicine Websites

Summary: 2014 AADR Satellite Symposium in Clinical Research Charlotte, North Carolina March 17-19, 2014 in Oral Health Research* will be offering its 2½ day course in clinical research as a Satellite Symposium for this AADR Satellite Symposium is separate from and DOES NOT include access to the AADR Annual Meeting

Klein, Ophir

257

Ocean Remote Sensing from Satellites Ted Strub, Burt 406

  Geosciences Websites

Summary: Ocean Remote Sensing from Satellites Ted Strub, Burt 406 tstrub@coas.oregonstate.edu http spill: Satellite "images" may "track" surface features: IR surface temperatures, visible features, ...??? What can we really see? #12;Early Days 1888Remote Sensing Pioneers #12;Why Satellites? · Oceans

Wright, Dawn Jeannine

258

Using Internet nodes and routers onboard satellites W. Ivancic,

  Engineering Websites

Summary: Using Internet nodes and routers onboard satellites L. Wood,@ W. Ivancic, D. Hodgson,+* E. Miller of Satellite Communications and Networking. Copyright © 2007 John Wiley & Sons, Ltd. http://www.interscience.wiley.com/ @ Cisco Systems Global Government Solutions Group, Bedfont Lakes, London, England. * Surrey Satellite

Wood, Lloyd

259

Mary E. Kicza Assistant Administrator for Satellite & Information Services

  Environmental Sciences and Ecology Websites

Summary: Mary E. Kicza Assistant Administrator for Satellite & Information Services National Oceanic and Atmospheric Administration (NOAA) Mary E.Kicza is the NOAA Assistant Administrator for Satellite and Information Services. NOAA Satellite and Information Service is dedicated to providing timely access to global


260

Satellite Meeting to the EBBS 2007 Conference 15 September 2007

  Biology and Medicine Websites

Summary: Satellite Meeting to the EBBS 2007 Conference 15 September 2007 Stress, Brain and Behaviour Recent, an important goal of this meeting is to promote discussions. The Satellite will start at 10:30 and last till 17: Registration fees for the EBBS conference include participation of the Satellite. In case you want to attend

Treves, Alessandro

261

On the perturbations on satellites probing General Relativity

  General Relativity & Quantum Cosmology (arXiv)

Summary: Non-gravitational Yarkovsky-Rubincam effect for LAGEOS and LAGEOS 2 satellites used to probe General Relativity has been revealed by means of the Kolmogorov analysis of their perturbations. We present the method and its efficiency at modeling of generated systems with properties expected at the satellite laser ranging measurements and then at satellite residual data analysis.

S. Sargsyan; G. Yegorian; S. Mirzoyan
2013-12-19

262

Revised 2007-Jan-09 Irregular Satellites of the Planets

  Physics Websites

Summary: Revised 2007-Jan-09 Irregular Satellites of the Planets: Capture Processes in the Early Solar in the Solar system possess irregular satellites, charac- terized by large, highly eccentric and/or inclined orbits that are distinct from the nearly circular, uninclined orbits followed by the regular satellites

Jewitt, David C.

263

On the Life and Death of Satellite Haloes

  Astrophysics (arXiv)

Summary: We study the evolution of dark matter satellites orbiting inside more massive haloes using semi-analytical tools coupled with high-resolution N-Body simulations. We select initial satellite sizes, masses, orbital energies, and eccentricities as predicted by hierarchical models of structure formation. Both the satellite and the main halo are described by a Navarro, Frenk & White density profile with various concentrations.

Giuliano Taffoni; Lucio Mayer; Monica Colpi; Fabio Governato
2003-01-14

264

Satellite Communications David Hart, dhart@cis.ohio-state.edu

  Computer Technologies and Information Sciences Websites

Summary: Satellite Communications David Hart, dhart@cis.ohio-state.edu This paper is intended to give an overview of that methods of and uses for satellite communications, in addition to presenting recent trends Page Table of Contents Introductionq Basic Elementsq Various Uses of Satellite Communications

Jain, Raj

265

Tectonics of the outer planet satellites Geoffrey C. Collins

  Geosciences Websites

Summary: 7 Tectonics of the outer planet satellites Geoffrey C. Collins Wheaton College, Norton William B. Schenk Lunar and Planetary Institute, Houston Summary Tectonic features on the satellites of the outer planets range from the familiar, such as clearly recognizable graben on many satellites, to the bizarre

Nimmo, Francis

266

2014 Benefits Satellite Office Schedule Date Time Location

  Biology and Medicine Websites

Summary: 2014 Benefits Satellite Office Schedule Date Time Location January 21st 1:00 ­ 4:00 pm Campus ­ 305 June 17th SATELLITE OFFICE CANCELLED July 15th 1:00 ­ 4:00 pm Campus Center - 309 August 19th 1 December 16th 1:00 ­ 4:00 pm Campus Center - 305 Satellite Offices provide a central location on campus

Zhou, Yaoqi

267

Micro-Navigation Satellite Network Design and Analysis

  Engineering Websites

Summary: Micro-Navigation Satellite Network Design and Analysis Bei Kang, Electrical and Computer of Satellite Communications Systems. He joined academia in 2000 at the University of North Dakota, satellite control, and sensor networking. ABSTRACT Accurate position and orientation data are the bases

Won, Chang-Hee

268

Methods for verifying satellite precipitation estimates Elizabeth E. Ebert

  Geosciences Websites

Summary: 1 Methods for verifying satellite precipitation estimates Elizabeth E. Ebert Bureau of Meteorology, Melbourne, Australia Introduction Satellite precipitation estimates are widely used to measure global rainfall on monthly timescales for climate studies (e.g., Huffman et al., 1997). Near real time satellite

Ebert, Beth

269

SATELLITES OF LEGENDRIAN KNOTS AND REPRESENTATIONS OF THE CHEKANOVELIASHBERG

  Mathematics Websites

Summary: SATELLITES OF LEGENDRIAN KNOTS AND REPRESENTATIONS OF THE CHEKANOV­ELIASHBERG ALGEBRA LENHARD NG AND DAN RUTHERFORD Abstract. We study satellites of Legendrian knots in R3 and their relation has finite-dimensional representations if and only if there exist certain rulings of satellites

Ng, Lenny

270

ASTRONOMY 300B: Satellite Presentation Project Fall 2011

  Physics Websites

Summary: ASTRONOMY 300B: Satellite Presentation Project Fall 2011 Prof. Bechtold (after a class important points to get across. The Assignment. You are the project manager for an astronomical satellite the committee, your satellite will be decommissioned and allowed to burn up in the atmosphere. Prepare

Bechtold, Jill

271

An abundant population of small irregular satellites around Jupiter

  Physics Websites

Summary: irregular satellites around Jupiter Scott S. Sheppard & David C. Jewitt Institute for Astronomy, University ............................................................................................................................................................................. Irregular satellites have eccentric orbits that can be highly inclined or even retrograde relative the regular satellites that follow unin- clined, nearly circular and prograde orbits1 . Rather

Jewitt, David C.

272

ighly capable small satellites are commonplace today, but this was-

  Physics Websites

Summary: H ighly capable small satellites are commonplace today, but this was- n't always the case. It wasn't until the late 1980s that modern small satellites came on the scene. This new breed of low-profile, low category? A precise description of small satellites, or "lightsats," as they were also called, was lacking

Rhoads, James

273

THE CROSSING NUMBER OF SATELLITE KNOTS MARC LACKENBY

  Mathematics Websites

Summary: THE CROSSING NUMBER OF SATELLITE KNOTS MARC LACKENBY 1. Introduction One of the most basic ). Connected sums are particular cases of satellite knots, which are defined as follows. Let L be a non­trivial knot in the 3­sphere. Then a knot K is a satellite knot with companion knot L if K lies in a regular

Lackenby, Marc

274

TCP SPLITTING PROTOCOL FOR BROADBAND AERONAUTICAL SATELLITE NETWORK

  Engineering Websites

Summary: TCP SPLITTING PROTOCOL FOR BROADBAND AERONAUTICAL SATELLITE NETWORK Yadong Shang, Michael Hadjitheodosiou, Center for Satellite & Hybrid Communication Networks, Institute for Systems Research, University for an aeronautical network supporting Internet and data services via satellite. For the future IP-based aeronautical

Baras, John S.

275

Peer-to-Peer Refueling for Circular Satellite Constellations

  Engineering Websites

Summary: Peer-to-Peer Refueling for Circular Satellite Constellations Haijun Shen and Panagiotis Tsiotras In this paper, we study the scheduling problem arising from refueling multiple satellites in a circular. Instead, all satellites in the constellation are assumed to be capable of refueling each other (peer

Tsiotras, Panagiotis

276

Ris National Laboratory Satellite SAR applied in offshore wind

  Multidisciplinary Databases and Resources Websites

Summary: Risø National Laboratory Satellite SAR applied in offshore wind ressource mapping: possibilities is to quantify the regional offshore wind climate for wind energy application based on satellite SAR ·Study of 85 Upwind footprints for the Horns Rev mast Wind direction #12;R.J.Barthelmie and S.C.Pryor, Can satellite


277

FAST INTERPOLATION FOR GLOBAL POSITIONING SYSTEM (GPS) SATELLITE

  Mathematics Websites

Summary: FAST INTERPOLATION FOR GLOBAL POSITIONING SYSTEM (GPS) SATELLITE ORBITS Beny Neta Naval typicallycon- sists of satellite positions at evenly spaced times over a week. Most ephemeris are given at 900 sec (15 min) time steps although the NGS ones are at 1200 sec (20 min). The GPS satellites are in 12

Danielson, Don

278

Des satellites nous renvoient notre image Politique scientifique fdrale

  Mathematics Websites

Summary: Des satellites nous renvoient notre image Politique scientifique fédérale Martine STÉLANDRE Faites, HEPL Sualem, ISELL, Hemes et ULg 2 Les satellites observent la Terre En l'an 2002, plus de 5.000 satellites flottaient autour de la Terre, dont environ 600 sont en fonctionnement. Ce sont des outils

Liège, Université de

279

Virtual Genus of Satellite Links Daniel S. Silver

  Mathematics Websites

Summary: Virtual Genus of Satellite Links Daniel S. Silver Susan G. Williams Department of Mathematics and Statistics, University of South Alabama February 10, 2013 Abstract The virtual genus of a virtual satellite. Then ~= ~1 · · · ~d is a satellite link of with com- panion . It is clear that the virtual genus

Williams, Susan

280

An Integrated Evolutionary Model Approach to Small Satellite Engineering

  Engineering Websites

Summary: An Integrated Evolutionary Model Approach to Small Satellite Engineering 2LT Joseph B. Robinson Approach to Small Satellite Engineering 2LT Joseph B. Robinson, Col (Ret.) John Keesee, David W. Miller May Model Approach to Small Satellite Engineering by Joseph B. Robinson Submitted to the Department


281

Use of Visible Geostationary Operational Meteorological Satellite Imagery in

  Environmental Management and Restoration Websites

Summary: 10 Use of Visible Geostationary Operational Meteorological Satellite Imagery in Mapping Reference radiation (insolation, or Rs) have been made from geostationary satellite data over a 14-year period (1 June estimation (Paech et al., 2009). Clearly, geostationary satellites provide spatially and temporally


282

Indian Regional Navigation Satellites System (IRNSS) is the world's rst

  Engineering Websites

Summary: Indian Regional Navigation Satellites System (IRNSS) is the world's rst regional navigation system with its footprint primarily over the Indian subcontinent. The system is expected to have seven satellites in all, with three satellites in GEO stationary and four in GEO synchronous orbits (Kibe & Gowrishankar

Calgary, University of

283

Irregular Satellites of the Planets: Products of Capture

  Physics Websites

Summary: Irregular Satellites of the Planets: Products of Capture in the Early Solar System David Jewitt satellites, characterized by large, highly eccentric and/or inclined orbits that are distinct from the nearly circular, uninclined orbits of the regular satellites. This difference can be traced directly to different

Jewitt, David C.

284

MULTIPLICITY OF COMPLEX HYPERSURFACE SINGULARITIES, ROUCHE SATELLITES AND ZARISKI'S PROBLEM

  Mathematics Websites

Summary: MULTIPLICITY OF COMPLEX HYPERSURFACE SINGULARITIES, ROUCH´E SATELLITES AND ZARISKI'S PROBLEM singularit´es d'hypersurfaces complexes, satellites de Rouch´e et probl`eme de Zariski. Soient f, g : (Cn , 0 such an inequality a Rouch´e inequality and we say that g is a Rouch´e satellite of f . In Section 3, we apply

Gasparim, Elizabeth

285

IP ROUTING ISSUES IN SATELLITE CONSTELLATION NETWORKS A. CLERGET,2

  Engineering Websites

Summary: 1 IP ROUTING ISSUES IN SATELLITE CONSTELLATION NETWORKS L. WOOD,*1 A. CLERGET,2 I. ANDRIKOPOULOS,1 of an article accepted for publication in the International Journal of Satellite Communications Special Issue on Internet Protocols over Satellite, vol. 18 no.6, Nov/Dec 2000. Copyright © 1999, 2000 John Wiley and Sons

Wood, Lloyd

286

How Many GNSS Satellites are GRACE XINGXIN GAO, Member, IEEE

  Engineering Websites

Summary: How Many GNSS Satellites are Too Many? GRACE XINGXIN GAO, Member, IEEE University of Illinois at Urbana--Champaign PER ENGE, Fellow, IEEE Stanford University Global Navigation Satellite Systems (GNSS systems. Along with the growth of the systems, the number of satellites will also increase. The whole

Gao, Grace Xingxin

287

Which Transport Protocol for Hybrid Terrestrial and Satellite Systems?

  Physics Websites

Summary: Which Transport Protocol for Hybrid Terrestrial and Satellite Systems? Ihsane Tou1,2 , Pascal, 31400, Toulouse, France {firstname.lastname}@{laas|astrium|cnes}.fr, Abstract. Satellite systems. Moreover, the natural broadcasting capacity of satellite networks makes it a good companion to terrestrial

Paris-Sud XI, Université de

288

Network Mobility in Satellite Networks: Architecture and the Protocol

  Computer Technologies and Information Sciences Websites

Summary: 1 Network Mobility in Satellite Networks: Architecture and the Protocol Abu Zafar M. Shahriar}@ou.edu William Ivancic Satellite Networks and Architectures Branch NASA Glenn Research Center, Cleveland, OH for multiple IP-enabled devices onboard a satellite that hands off between ground stations. Network Mo- bility

Atiquzzaman, Mohammed

289

TOWARDS NAVIGATION BASED ON 120 SATELLITES: ANALYZING THE NEW SIGNALS

  Engineering Websites

Summary: TOWARDS NAVIGATION BASED ON 120 SATELLITES: ANALYZING THE NEW SIGNALS A DISSERTATION SUBMITTED Satellite Systems (GNSS) are experiencing a new era. The US Global Positioning System (GPS) now serves over is developing the Galileo system that promises to place 30 more satellite in medium Earth orbit

Stanford University

290

Response of Burrowing Owls to Experimental Removal of Satellite Burrows

  Environmental Sciences and Ecology Websites

Summary: Note Response of Burrowing Owls to Experimental Removal of Satellite Burrows NOELLE A. RONAN,1 of post-emergent nestlings. We experimentally blocked access to burrows within 20 m of nests (satellite burrowing owls to removal of satellite burrows. We compared reproductive performance and nest fidelity

Rosenberg, Daniel K.

291

Virtual Genus of Satellite Links Daniel S. Silver

  Mathematics Websites

Summary: Virtual Genus of Satellite Links Daniel S. Silver Susan G. Williams Department of Mathematics and Statistics, University of South Alabama January 21, 2013 Abstract The virtual genus of a virtual satellite. Then ~= ~1 · · · ~d is a satellite link of with com- panion . It is clear that the virtual genus

Silver, Dan

292

SATELLITE MOTION AROUND AN OBLATE PLANET: A PERTURBATION SOLUTION FOR

  Mathematics Websites

Summary: SATELLITE MOTION AROUND AN OBLATE PLANET: A PERTURBATION SOLUTION FOR ALL ORBITAL PARAMETERS D. A Abstract The search for a universal solution of the equations of motion for a satellite orbiting an oblate for predict- ing satellite orbits that is more accurate than the two-body formulas. These predictions

Danielson, Don

293

Optimal Scheduling for Servicing Multiple Satellites in a Circular Constellation

  Engineering Websites

Summary: Optimal Scheduling for Servicing Multiple Satellites in a Circular Constellation Haijun Shen the scheduling of servicing multiple satellites in a circular orbit. Specifically, one servicing spacecraft (SSc) is considered to be initially on the circular orbit of the satellites to be serviced. The SSc then rendezvous

Tsiotras, Panagiotis

294

Evaluation of the Route Optimization for NEMO in Satellite Networks

  Computer Technologies and Information Sciences Websites

Summary: Evaluation of the Route Optimization for NEMO in Satellite Networks Abu Zafar M. Shahriar,atiq}@ou.edu William D. Ivancic Satellite Networks and Architectures Branch NASA Glenn Research Center Cleveland, OH architecture that has been proposed for satellite networks to manage the mobility of Internet Protocol

Atiquzzaman, Mohammed

295

High Speed Internet Access Through Unidirectional Geostationary Satellite Channels

  Computer Technologies and Information Sciences Websites

Summary: High Speed Internet Access Through Unidirectional Geostationary Satellite Channels Ina Minei Reuven user to a direct satellite channel, at a speed 20 times faster than that of an average telephone modem. Communication over satellite links is often characterized by sporadic high bit-error rates and burst losses

Cohen, Reuven

296

Ocean Remote Sensing from Satellites Ted Strub, Burt 406

  Geosciences Websites

Summary: Ocean Remote Sensing from Satellites Ted Strub, Burt 406 tstrub@coas.oregonstate.edu http & Currents ­ Surface Wind Stress · New technology #12;http://response.restoration.noaa.gov/ Satellite images are being used to track the Gulf Coast oil spill. What can we really "see" in the ocean, using satellites

Wright, Dawn Jeannine

297

HTTPEP: a HTTP Performance Enhancing Proxy for Satellite Systems

  Computer Technologies and Information Sciences Websites

Summary: HTTPEP: a HTTP Performance Enhancing Proxy for Satellite Systems Paul Davern, Noor Nashid, Cormac J Communications, Cairo University, Cairo, Egypt. azahran@eecu.cu.edu.eg Broadband satellites enable Internet) that accelerates web-browsing and improves the utilization of satellite resources. We describe HTTP optimizations

Sreenan, Cormac J.

298

Scalable Proportional Allocation of Bandwidth in IP Satellite Networks12

  Computer Technologies and Information Sciences Websites

Summary: 1 Scalable Proportional Allocation of Bandwidth in IP Satellite Networks12 A. Durresi, P. K December 10, 2002 Abstract--Proposed satellite constellation networks, based on Geostationary Earth Orbit (GEO) satellites, Medium Earth Orbit (MEO), and Low Earth Orbit (LEO) systems, will be required

Jain, Raj

299

Mirror Routing for Satellite Networks With Cross-layer Optimization

  Computer Technologies and Information Sciences Websites

Summary: Mirror Routing for Satellite Networks With Cross-layer Optimization Zhijiang Chang, Georgi have been proposed for routing in the Low Earth Orbit (LEO) satellite networks. The multi-layered routing ap- proaches are envisioned as promising because they use Middle Earth Orbit (MEO) satellite

Kuzmanov, Georgi

300

A Novel Dimensioning Method For High Throughput Satellite Design

  Physics Websites

Summary: A Novel Dimensioning Method For High Throughput Satellite Design Dimitri Serrano-Velarde, Emmanuel satellite (HTS) for broadband communications. The method is based on the optimization of performance is adaptable to any kind of service area. A digital video broadcasting satellite second generation (DVB-S2) air

Paris-Sud XI, Université de

301

On the perturbations on satellites probing General Relativity

  CERN Preprints

Summary: Non-gravitational Yarkovsky-Rubincam effect for LAGEOS and LAGEOS 2 satellites used to probe General Relativity has been revealed by means of the Kolmogorov analysis of their perturbations. We present the method and its efficiency at modeling of generated systems with properties expected at the satellite laser ranging measurements and then at satellite residual data analysis.

Sargsyan, S; Mirzoyan, S
2013-01-01

302

A model for improving ocean wind forecasts using satellite

  Mathematics Websites

Summary: A model for improving ocean wind forecasts using satellite measurements Anders Malmberg IFREMER, PLOUZAN� 18TH SEPTEMBER 2003 A model for improving ocean wind forecasts using satellite measurements ­ p.1 the forecast? A model for improving ocean wind forecasts using satellite measurements ­ p.2/18 #12;Recall

Malmberg, Anders

303

TOWARDS USING SATELLITE ALTIMETRY FOR THE OBSERVATION OF COASTAL DYNAMICS.

  Environmental Sciences and Ecology Websites

Summary: TOWARDS USING SATELLITE ALTIMETRY FOR THE OBSERVATION OF COASTAL DYNAMICS. Florence Birol (1 be observed with satellite altimetry. Therefore, we have used a new data processing approach developed. SATELLITE ALTIMETRY IN THE COASTAL DOMAIN: DEVELOPMENTS The new processing was originally developed


304

WDM Polymer Substrate Mode Photonic Interconnects for Satellite Communications

  Engineering Websites

Summary: WDM Polymer Substrate Mode Photonic Interconnects for Satellite Communications Jian Liu Polar is an enabling technology for future satellite communications to increase capacity ofbandwidth and network-3]. Compared with RF satellite communications, they use much smaller antenna aperture size and consume less

Chen, Ray

305

FORMATION FLYING SATELLITE CONTROL UTILIZING INPUT SHAPING Erika Biediger

  Engineering Websites

Summary: recognizable being solar panels and communications antennae. Many flexible satellites are positionedAAS 03-591 FORMATION FLYING SATELLITE CONTROL UTILIZING INPUT SHAPING Erika Biediger William of the difficulties with formation flying is that the satellites must be autonomous and able to generate and correct

Singhose, William

306

GROUP SIZE ESTIMATION FOR HYBRID SATELLITE/TERRESTRIAL RELIABLE

  Computer Technologies and Information Sciences Websites

Summary: hop. Satellite communications seem too expensive at first sight. Neverthe- less, in the context updates. Satellite communications are prone to transmission errors (due to atmo- spheric perturbations the satellite communication) grows. Consequently, the pro- posed approach consists of transmitting data via

Mailhes, Corinne

307

SCALABLE AND ROBUST RELIABLE MULTICAST FOR SATELLITE NETWORKS Kyriakos Manousakis

  Engineering Websites

Summary: Center for Satellite and Hybrid Communication Networks University of Maryland, College Park College Park efficiently. One way of accomplishing that is by using multicast communication between the satellite1 SCALABLE AND ROBUST RELIABLE MULTICAST FOR SATELLITE NETWORKS Kyriakos Manousakis John S. Baras

Baras, John S.

308

SATELLITE ATM NETWORK ARCHITECTURAL CONSIDERATIONS AND TCP IP PERFORMANCE1

  Computer Technologies and Information Sciences Websites

Summary: technology and Ka-Band satellite communications systems will lead to a vast array of opportunities for new in satellite communications exhibit an increased emphasis on new services as opposed to point-to-point data ATM networking is due to the several advantages o ered by satellite communications technology 3, 8

Jain, Raj

309

Interoperation and Integration of Satellite Based Augmentation Systems

  Engineering Websites

Summary: Interoperation and Integration of Satellite Based Augmentation Systems Richard Fuller, Donghai Dai development of Satellite Based Augmenta- tion Systems (SBASs). The Federal Aviation Admini- stration's Wide estimates will suffer this increase in uncertainty due to dramatic decreases in GPS satellite observability

Stanford University

310

Hundreds of Milky Way Satellites? Luminosity Bias in the Satellite Luminosity Function

  Astrophysics (arXiv)

Summary: We correct the observed Milky Way satellite luminosity function for luminosity bias using published completeness limits for the Sloan Digital Sky Survey DR5. Assuming that the spatial distribution of Milky Way satellites tracks the subhalos found in the Via Lactea LCDM N-body simulation, we show that there should be between ~300 and ~600 satellites within 400 kpc of the Sun that are brighter than the faintest known dwarf galaxies, and that there may be as many as ~ 1000, depending on assumptions. By taking into account completeness limits, we show that the radial distribution of known Milky Way dwarfs is consistent with our assumption that the full satellite population tracks that of subhalos. These results alleviate the primary worries associated with the so-called missing satellites problem in CDM. We show that future, deep wide-field surveys such as SkyMapper, the Dark Energy Survey (DES), PanSTARRS, and the Large Synoptic Survey Telescope (LSST) will deliver a complete census of ultra-faint dwarf satellites out to the Milky Way virial radius, offer new limits on the free-streaming scale of dark matter, and provide unprecedented constraints on the low-luminosity threshold of galaxy formation.

Erik J. Tollerud; James S. Bullock; Louis E. Strigari; Beth Willman
2008-10-08

311

The dynamics of tidal tails from massive satellites

  Astrophysics (arXiv)

Summary: (Abbreviated) We investigate the dynamical mechanisms responsible for producing tidal tails from dwarf satellites using N-body simulations. We identify two important dynamical co-conspirators: 1) the points where the attractive force of the host halo and satellite are balanced do not occur at equal distances from the satellite centre or at the same equipotential value for massive satellites, breaking the morphological symmetry of the leading and trailing tails; and 2) the escaped ejecta in the leading (trailing) tail continues to be decelerated (accelerated) by the satellite's gravity leading to large offsets of the ejecta orbits from the satellite orbit. The effect of the satellite's self gravity decreases only weakly with a decreasing ratio of satellite mass to host halo mass, demonstrating the importance of these effects over a wide range of subhalo masses. Not only will the morphology of the leading and trailing tails for massive satellites be different, but the observed radial velocities of the tails will be displaced from that of the satellite orbit; both the displacement and the peak radial velocity is proportional to satellite mass. If the tails are assumed to follow the progenitor satellite orbits, the tails from satellites with masses greater than 0.0001 of the host halo virial mass in a spherical halo will appear to indicate a flattened halo. Therefore, a constraint on the Milky Way halo shape using tidal streams requires mass-dependent modelling. Similarly, we compute the the distribution of tail orbits both in E_{r}-r^{-2} space and in E-L_{z} space, advocated for identifying satellite stream relics. The acceleration of ejecta by a massive satellite during escape spreads the velocity distribution and obscures the signature of a well-defined ``moving group'' in phase space.

Jun-Hwan Choi; Martin D. Weinberg; Neal Katz
2007-08-03

312

Poster Abstract: Satellite Based Wireless Sensor Networks Global Scale Sensing with Nano-and Pico-Satellites

  Computer Technologies and Information Sciences Websites

Summary: Poster Abstract: Satellite Based Wireless Sensor Networks ­ Global Scale Sensing with Nano- and Pico-Satellites Walter Colitti Vrije Universiteit Brussel ETRO Dept. Pleinlaan 2, B-1050 Brussels systems of small sensor-equipped satellites improve the cost efficiency and the missions' performance

Dunkels, Adam

313

Search for Unknown Dark Matter Satellites of the Milky Way

  HEP - Phenomenology (arXiv)

Summary: We present a search for Galactic dark matter (DM) satellites using the Large Area Telescope (LAT). N-body simulations based on the Lambda-CDM model of cosmology predict a large number of as yet unobserved Galactic DM satellites. These satellites could potentially produce gamma rays through the self-annihilation of DM particles. Some DM satellites are expected to have hard gamma-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We searched for LAT sources with these characteristics. We found no candidate DM satellites matching these criteria in one year of LAT data and interpreted this result in the context of N-body simulations.

Alex Drlica-Wagner; Ping Wang; Elliott Bloom; Louis Strigari; for the Fermi-LAT Collaboration
2011-11-14

314

A new spin on disks of satellite galaxies

  CERN Preprints

Summary: We investigate the angular and kinematic distributions of satellite galaxies around a large sample of bright isolated primaries in the spectroscopic and photometric catalogues of the Sloan Digital Sky Survey (SDSS). We detect significant anisotropy in the spatial distribution of satellites. To test whether this anisotropy could be related to the rotating disks of satellites recently found by Ibata et al. in a sample of SDSS galaxies, we repeat and extend their analysis. Ibata et al. found an excess of satellites on opposite sides of their primaries having anticorrelated radial velocities. We find that this excess is sensitive to small changes in the sample selection criteria which can greatly reduce its significance. In addition, we find no evidence for correspondingly correlated velocities for satellites observed on the same side of their primaries, which would be expected for rotating disks of satellites. We conclude that the detection of coherent rotation in the satellite population in current observationa...

Cautun, Marius; Frenk, Carlos S; Sawala, Till
2014-01-01

315

Planetesimals and Satellitesimals: Formation of the Satellite Systems

  CERN Preprints

Summary: The origin of the regular satellites ties directly to planetary formation in that the satellites form in gas and dust disks around the giant planets and may be viewed as mini-solar systems, involving a number of closely related underlying physical processes. The regular satellites of Jupiter and Saturn share a number of remarkable similarities that taken together make a compelling case for a deep-seated order and structure governing their origin. Furthermore, the similarities in the mass ratio of the largest satellites to their primaries, the specific angular momenta, and the bulk compositions of the two satellite systems are significant and in need of explanation. Yet, the differences are also striking. We advance a common framework for the origin of the regular satellites of Jupiter and Saturn and discuss the accretion of satellites in gaseous, circumplanetary disks. Following giant planet formation, planetesimals in the planet's feeding zone undergo a brief period of intense collisional grinding. Mass deli...

Mosqueira, Ignacio; Turrini, Diego
2009-01-01

316

The Principle of Navigation Constellation Composed of SIGSO Communication Satellites

  CERN Preprints

Summary: The Chinese Area Positioning System (CAPS), a navigation system based on GEO communication satellites, was developed in 2002 by astronomers at Chinese Academy of Sciences. Extensive positioning experiments of CAPS have been performed since 2005. On the basis of CAPS, this paper studies the principle of navigation constellation composed of Slightly Inclined Geostationary Orbit (SIGSO) communication satellites. SIGSO satellites are derived from end-of-life Geostationary Orbit (GEO) satellites under inclined orbit operation. Considering the abundant frequency resources of SIGSO satellites, multi-frequency observations could be conducted to enhance the precision of pseudorange measurements and ameliorate the positioning performence. The constellation composed of two GEO satellites and four SIGSO satellites with inclination of 5 degrees can provide the most territory of China with 24-hour maximum PDOP less than 42. With synthetic utilization of the truncated precise (TP) code and physical augmentation factor in fo...

Ji, Hai-Fu; Ai, Guo-Xiang; Shi, Hu-Li
2012-01-01

317

Satellites in Discs: Regulating the Accretion Luminosity

  Astrophysics (arXiv)

Summary: We demonstrate, using a simple analytic model, that the presence of a massive satellite can globally modify the structure and emission properties of an accretion disc to which it is tidally coupled. We show, using two levels of numerical approximation, that the analytic model gives reasonable results. The results are applicable to two astrophysical situations. In the case of an active galactic nucleus, we consider the case of a $\\sim 10^3\\Msun$ compact companion to the central black-hole and show that it could modulate the emitted spectrum on a timescale of $\\sim10^5$ years. In the case of a T Tauri accretion disc, a satellite such as a sub-dwarf or giant planet could modify the disc spectral energy distribution over a substantial fraction of the T Tauri star lifetime.

Dave Syer; Cathie Clarke
1995-05-04

318

Efficient statistical classification of satellite measurements

  CERN Preprints

Summary: Supervised statistical classification is a vital tool for satellite image processing. It is useful not only when a discrete result, such as feature extraction or surface type, is required, but also for continuum retrievals by dividing the quantity of interest into discrete ranges. Because of the high resolution of modern satellite instruments and because of the requirement for real-time processing, any algorithm has to be fast to be useful. Here we describe an algorithm based on kernel estimation called Adaptive Gaussian Filtering that incorporates several innovations to produce superior efficiency as compared to three other popular methods: k-nearest-neighbour (KNN), Learning Vector Quantization (LVQ) and Support Vector Machines (SVM). This efficiency is gained with no compromises: accuracy is maintained, while estimates of the conditional probabilities are returned. These are useful not only to gauge the accuracy of an estimate in the absence of its true value, but also to re-calibrate a retrieved image and...

Mills, Peter
2012-01-01

319

Satellite measurement of the Hannay angle

  Astrophysics (arXiv)

Summary: The concept of a measurement of the yet unevaluated Hannay angle, by means of an Earth-bound satellite, adiabatically driven by the Moon, is shown herein. Numerical estimates are given for the angles, the orbital displacements, the shortening of the orbital periods, for different altitudes. It is concluded that the Hannay effect is measurable in high Earth orbits, by means of atomic clocks, accurate Time & Frequency transfer system and precise positioning.

Alessandro D. A. M. Spallicci
2004-09-20

320

Cloud structures from defense meteorological satellite data

  Texas A&M University - TxSpace

Summary: the Defense Meteorological Satellite Program (DMSP) data to determine the structure of cloud tops above the convective zone. The DMSP imagery was of the high-resolution infrared (IR) de- rived type with a subtrack resolution of 2. 4 n mi. The variable den...-gray-level density wedge, provided by the Air Weather Service, enabled determinations of ap- proximate cloud heights A comparison was made between the DMSP imagery and the concurrent digital radar from the National Severe Storms Laboratory at Norman...

Phillips, John Frederick
1975-01-01

321

Photometric Survey of the Irregular Satellites

  Astrophysics (arXiv)

Summary: We present BVRI colors of 13 Jovian and 8 Saturnian irregular satellites obtained with the 2.56m Nordic Optical Telescope on La Palma, the 6.5m Magellan Baade Telescope on La Campanas, and the 6m MMT on Mt. Hopkins. The observations were performed between December 2001 to March 2002. Nearly all of the known irregular satellites can be divided into two distinct classes based on their colors. One, the grey color class, has the similar colors to the C-type asteroid, and the other, the light red color class, has colors similar to P/D-type asteroids. We also find at least one object, the Jovian irregular J XXIII Kalyke, that has colors similar to the red colored Centaurs/TNOs, although its classification is unsecure. We also find that there is a correlation between the physical properties and dynamical properties of the irregular satellites. Most of the dynamical clusters have homogeneous colors, which points to single homogeneous progenitors being cratered or fragmented as the source of each individual cluster. The heterogeneous colored clusters are most easily explained by assuming that there are several dynamical clusters in the area, rather than just one.

Tommy Grav; Matthew J. Holman; Brett Gladman; Kaare Aksnes
2003-01-02

322

The reionization of galactic satellite populations

  CERN Preprints

Summary: We use high resolution simulations of the formation of the local group post-processed by a radiative transfer code for UV photons, to investigate the reionization of the satellite populations of an isolated Milky Way-M31 galaxy pair in a variety of scenarios. We use an improved version of ATON which includes a simple recipe for radiative feedback. In our baseline models, reionization is initiated by low mass, radiatively regulated haloes at high redshift, until more massive haloes appear, which then dominate and complete the reionization process. We investigate the relation between reionization history and present-day positions of the satellite population. We find that the average reionization redshift (zr) of satellites is higher near galaxy centers (MW and M31). This is due to the inside-out reionization patterns imprinted by massive haloes within the progenitor during the EoR, which end up forming the center of the galaxy. Thanks to incomplete dynamical mixing during galaxy assembly, these early patterns s...

Ocvirk, P; Aubert, D; Knebe, A; Libeskind, N; Chardin, J; Gottlöber, S; Yepes, G; Hoffman, Y
2014-01-01

323

Galaxy Satellites and the Weak Equivalence Principle

  HEP - Phenomenology (arXiv)

Summary: Numerical simulations of the effect of a long-range scalar interaction (LRSI) acting only on nonbaryonic dark matter, with strength comparable to gravity, show patterns of disruption of satellites that can agree with what is seen in the Milky Way. This includes the symmetric Sagittarius stellar stream. The exception presented here to the Kesden and Kamionkowski demonstration that an LRSI tends to produce distinctly asymmetric streams follows if the LRSI is strong enough to separate the stars from the dark matter before tidal disruption of the stellar component, and if stars dominate the mass in the luminous part of the satellite. It requires that the Sgr galaxy now contains little dark matter, which may be consistent with the Sgr stellar velocity dispersion, for in the simulation the dispersion at pericenter exceeds virial. We present other examples of simulations in which a strong LRSI produces satellites with large mass-to-light ratio, as in Draco, or free streams of stars, which might be compared to "orphan" streams.

J. A. Keselman; A. Nusser; P. J. E. Peebles
2009-08-29

324

Baffin Island Satellite Altimetry andSatellite Altimetry and SeaglidersSeagliders: observing high: observing high--latitude ocean climatelatitude ocean climate

  Geosciences Websites

Summary: deep convhave shown that offshore flow from Greenland controls deep convection andection and LabradorBaffin Island Labrador Satellite Altimetry andSatellite Altimetry and SeaglidersHere we combine satellite altimetry with deep diving autonomousdeep diving autonomous Seagliders


325

Color Dependence in the Spatial Distribution of Satellite Galaxies

  Astrophysics (arXiv)

Summary: We explore the color dependence of the radial profile of satellite galaxies around isolated parent galaxies. Samples of potential satellites selected from large galaxy redshift surveys are significantly contaminated by interlopers -- objects not bound to the parent galaxy. We use the Sloan Digital Sky Survey to estimate the interloper fraction in samples of candidate satellite galaxies. We show that samples of red and blue satellites have different interloper populations: a larger fraction of blue galaxies are likely to be interlopers compared to red galaxies. Both with and without interloper subtraction, the radial profile of blue satellites is significantly shallower than that of red satellites. In addition, while red and blue primaries have different interloper fractions, the slope of the corrected radial profiles are consistent after interloper correction. We discuss the implications of these results for galaxy formation models.

Jacqueline Chen
2008-04-08

326

A Region Void of Irregular Satellites Around Jupiter

  CERN Preprints

Summary: An interesting feature of the giant planets of our solar system is the existence of regions around these objects where no irregular satellites are observed. Surveys have shown that, around Jupiter, such a region extends from the outermost regular satellite Callisto, to the vicinity of Themisto, the innermost irregular satellite. To understand the reason for the existence of such a satellite-void region, we have studied the dynamical evolution of Jovian irregulars by numerically integrating the orbits of several hundred test particles, distributed in a region between 30 and 80 Jupiter-radii, for different values of their semimajor axes, orbital eccentricities, and inclinations. As expected, our simulations indicate that objects in or close to the influence zones of the Galilean satellites become unstable because of interactions with Ganymede and Callisto. However, these perturbations cannot account for the lack of irregular satellites in the entire region between Callisto and Themisto. It is suggested that at ...

Haghighipour, N
2008-01-01

327

LARES succesfully launched in orbit: satellite and mission description

  CERN Preprints

Summary: On February 13th 2012, the LARES satellite of the Italian Space Agency (ASI) was launched into orbit with the qualification flight of the new VEGA launcher of the European Space Agency (ESA). The payload was released very accurately in the nominal orbit. The name LARES means LAser RElativity Satellite and summarises the objective of the mission and some characteristics of the satellite. It is, in fact, a mission designed to test Einstein's General Relativity Theory (specifically 'frame dragging' and Lense-Thirring effect). The satellite is passive and covered with optical retroreflectors that send back laser pulses to the emitting ground station. This allows accurate positioning of the satellite, which is important for measuring the very small deviations from Galilei-Newton's laws. In 2008, ASI selected the prime industrial contractor for the LARES system with a heavy involvement of the universities in all phases of the programme, from the design to the construction and testing of the satellite and separation...

Paolozzi, Antonio
2013-01-01

328

Some Implications of the Anisotropic Distribution of Satellite Galaxies

  Astrophysics (arXiv)

Summary: We examine a possible connection between the anisotropic distribution of satellite galaxies around giant spiral galaxies and the evolution of satellite systems. The observed polar anisotropy (Zaritsky et al.1997) is either imprinted by initial conditions or develops from an initially symmetric distribution. We attempt to discriminate between these two possibilities by exploring the implications of the latter one. From the observed distribution of satellite galaxies relative to the primary galaxy's disk, we derive constrains on the orbital inclinations of the current satellite population. Using this derived inclination limit and assuming that the initial population had no preferred orbital inclination, we estimate the size of the hypothesized original population. We find that our best-fit models imply a population of destroyed (or inhibited) satellites whose combined luminosity (assuming the same M/L as for the observed satellites) is between 18% and 103% of the current disk luminosity.

Dennis Zaritsky; Anthony H. Gonzalez
1999-08-17

329

From Tidal Dwarf Galaxies to Satellite Galaxies

  Astrophysics (arXiv)

Summary: Cosmological models have granted dwarf galaxies a key role: their properties constrain the distribution of dark matter and the physical evolution of their hosts. There is increasing evidence that objects with masses of dwarf galaxies form in the tidal tails of colliding galaxies and speculations that they could become satellite-like galaxies around their progenitors and thus be cosmologically important. Yet, whether these "Tidal Dwarf Galaxies" (TDGs) candidates are really long-lived and not only present in young interacting systems is still an open question to which numerical simulations may give answers. We present a set of 96 simulations of colliding galaxies with various mass ratios and encounter geometries, and statistically study the evolution of their TDG candidates. Among the 593 substructures initially identified in tidal tails, about 75% fall back onto their progenitor or are disrupted in a few 10^8 years. The remaining 25% become long-lived bound objects that typically survive more than 2Gyr with masses above 10^8 M_sun. These long-lived, satellite-like objects, are found to form in the outer most regions of the tidal tails. We infer several basic properties that dwarf galaxies should meet to have a tidal origin and apply these criteria to the Local Group dwarfs. We also find that the presence of TDGs would foster the anisotropy observed in the distribution of satellite galaxies around their host. Identifying the conditions required for interacting systems to form long-lived tidal dwarfs, we roughly estimate their contribution to the overall population of dwarfs. We conclude that a small but significant fraction of them - typically a few percent, and possibly more in dense environments or around early-type galaxies - could be of tidal origin.

F. Bournaud; P. -A. Duc
2006-05-15

330

The Anisotropic Distribution of Galactic Satellites

  Astrophysics (arXiv)

Summary: We present a study of the spatial distribution of subhalos in galactic dark matter halos using dissipationless cosmological simulations of the concordance LCDM model. We find that subhalos are distributed anisotropically and are preferentially located along the major axes of the triaxial mass distributions of their hosts. The Kolmogorov-Smirnov probability for drawing our simulated subhalo sample from an isotropic distribution is P_KS \\simeq 1.5 \\times 10^{-4}. An isotropic distribution of subhalos is thus not the correct null hypothesis for testing the CDM paradigm. The nearly planar distribution of observed Milky Way (MW) satellites is marginally consistent (probability \\simeq 0.02) with being drawn randomly from the subhalo distribution in our simulations. Furthermore, if we select the subhalos likely to be luminous, we find a distribution that is consistent with the observed MW satellites. In fact, we show that subsamples of the subhalo population with a centrally-concentrated radial distribution, similar to that of the MW dwarfs, typically exhibit a comparable degree of planarity. We explore the origin of the observed subhalo anisotropy and conclude that it is likely due to (1) preferential accretion of subhalos along filaments, often closely aligned with the major axis of the host halo, and (2) evolution of satellite orbits within the prolate, triaxial potentials typical of CDM halos. Agreement between predictions and observations requires the major axis of the outer dark matter halo of the Milky Way to be nearly perpendicular to the disk. We discuss possible observational tests of such disk-halo alignment with current large galaxy surveys.

Andrew R. Zentner; Andrey V. Kravtsov; Oleg Y. Gnedin; Anatoly A. Klypin
2005-04-23

331

An analysis of the properties of VAS satellite soundings

  Texas A&M University - TxSpace

Summary: temperature and moisture between satellite and rawinsonde derived soundings, The differences are related to atmospheric structure and highly dependent on the synoptic and mesoscale features measured by the rawinsonde. In addition to the statistical... analysis, synoptic and mesoscale analyses derived from both satellite and rawi nsonde data were compared. Comparison of synoptic scale analyses show that satellite data repre- sent large scale systems reasonably well, but mesoscale systems are poorly...

Rhodes, Robert Charles
1984-01-01

332

A Survey for Outer Satellites of Mars: Limits to Completeness

  Astrophysics (arXiv)

Summary: We surveyed the Hill sphere of Mars for irregular satellites. Our search covered nearly the entire Hill Sphere, but scattered light from Mars excluded the inner few arcminutes where the satellites Phobos and Deimos reside. No new satellites were found to an apparent limiting red magnitude of 23.5, which corresponds to radii of about 0.09 km using an albedo of 0.07.

Scott S. Sheppard; David Jewitt; Jan Kleyna
2004-09-22

333

Wind energy calculated from SAR and scatterometer satellite data

  Multidisciplinary Databases and Resources Websites

Summary: 1 Slide no. 4 Wind energy calculated from SAR and scatterometer satellite data Charlotte Bay: In-situ and satellite wind speed #12;9 Slide no. 4 0.0 5.0 10.0 15.0 0.0 5.0 10.0 15.0 Wind speed in-situ and satellite wind speed with linear regression #12;1 0 Slide no. 4 Comparison III Linear regression results


334

Spatial and kinematic alignments between central and satellite halos

  Astrophysics (arXiv)

Summary: Based on a cosmological N-body simulation we analyze spatial and kinematic alignments of satellite halos within six times the virial radius of group size host halos (Rvir). We measure three different types of spatial alignment: halo alignment between the orientation of the group central substructure (GCS) and the distribution of its satellites, radial alignment between the orientation of a satellite and the direction towards its GCS, and direct alignment between the orientation of the GCS and that of its satellites. In analogy we use the directions of satellite velocities and probe three further types of alignment: the radial velocity alignment between the satellite velocity and connecting line between satellite and GCS, the halo velocity alignment between the orientation of the GCS and satellite velocities and the auto velocity alignment between the satellites orientations and their velocities. We find that satellites are preferentially located along the major axis of the GCS within at least 6 Rvir (the range probed here). Furthermore, satellites preferentially point towards the GCS. The most pronounced signal is detected on small scales but a detectable signal extends out to 6 Rvir. The direct alignment signal is weaker, however a systematic trend is visible at distances < 2 Rvir. All velocity alignments are highly significant on small scales. Our results suggest that the halo alignment reflects the filamentary large scale structure which extends far beyond the virial radii of the groups. In contrast, the main contribution to the radial alignment arises from the adjustment of the satellite orientations in the group tidal field. The projected data reveal good agreement with recent results derived from large galaxy surveys. (abridged)

A. Faltenbacher; Y. P. Jing; Cheng Li; Shude Mao; H. J. Mo; Anna Pasquali; Frank C. van den Bosch
2007-12-18

335

Andromeda and its satellites - a kinematic perspective

  CERN Preprints

Summary: Using spectroscopic data taken with Keck II DEIMOS by the Z-PAndAS team in the Andromeda-Triangulum region, I present a comparison of the disc and satellite systems of Andromeda with those of our own Galaxy. I discuss the observed discrepancies between the masses and scale radii of Andromeda dwarf spheroidal galaxies of a given luminosity with those of the Milky Way. I also also present an analysis of the newly discovered M31 thick disc, which is measured to be hotter, more extended and thicker than that seen in the Milky Way.

Collins, Michelle L M; Chapman, Scott C
2012-01-01

336

Cloud structures from defense meteorological satellite data 

  Texas A&M University - TxSpace

Summary: ) number 2, German ballistic missile developed during World War II very High Resolution visual imagery from DMSP, resolution is 0. 33 n mi at subtrack VIL Mapped Vertically ? Integrated liquid-water content Very-High Resolution IR, refers to DMSp... the Defense Meteorological Satellite Program (DMSP) data to determine the structure of cloud tops above the convective zone. The DMSP imagery was of the high-resolution infrared (IR) de- rived type with a subtrack resolution of 2. 4 n mi. The variable den...

Phillips, John Frederick
1975-01-01

337

Satellite based retrieval of aerosol optical thickness: The effect of sun and satellite geometry

  Environmental Sciences and Ecology Websites

Summary: in the visible and near infrared part of the spectrum that can be used for AOD (Aerosol Optical Depth) retrieval satellite multi-spectral instruments (at visible and near infrared wavelengths) can be used to estimate AOD. Small pixel size (5 m  5 m in the visible and 20 m  20 m in the infrared) eliminates most sub


338

Satellite Data Assimilation forSatellite Data Assimilation for Naval Undersea CapabilityNaval Undersea Capability

  Geosciences Websites

Summary: of satellite altimeters necessary to ensure maximum weapon effectiveness · To determine the point at which additional altimeter input no longer increases weapon effectiveness #12;Modular Ocean Data Assimilation provides more realistic ocean environment. · Difference in weapon acoustic preset between using MODAS

Chu, Peter C.

339

Designing Satellite Communication Networks by Zero-One Quadratic Programming

  MIT - DSpace

Summary: In satellite communications networks, distinctive facilities called homing stations perform special transmission functions. Local demand nodes clustered around each homing station communicate with each other via a local ...

Helme, Marcia P.

340

Title: IKONOS Satellite Image of North York, Ontario Data Creator /

  Computer Technologies and Information Sciences Websites

Summary: Title: IKONOS Satellite Image of North York, Ontario Data Creator / Copyright Owner: Geo of approximately 10 metres Original Image ID: 20090901163045200000116082042000046195600THC Image Date: September 11


341

Notes to Saturn satellites Ijiraq and Kiviuq mutual close encounters

  Astrophysics (arXiv)

Summary: The problem of origin of outer irregular satellites of large planets is considered. The capture way of their origin most probable, however there is not detail theory. There are a number of irregular satellites, discovered in recent time. It gives an ability to investigate the statistics of orbital interaction and try to reconstruct real collision history of these objects We restrict this consideration by pair of orbits with close elements: Kiviuq and Ijiraq and determine period of close encounters between this satellites. It may be considered as a first step on road to the construction of theory of origin of the abundant class of irregular satellites.

A. E. Rosaev
2006-02-01

342

The dynamics of satellite disruption in cold dark matter haloes

  Astrophysics (arXiv)

Summary: We investigate the physical mechanisms of tidal heating and satellite disruption in cold dark matter host haloes using N-body simulations based on cosmological initial conditions. We show the importance of resonant shocks and resonant torques with the host halo to satellite heating. A resonant shock (torque) couples the radial (tangential) motion of a satellite in its orbit to its phase space. For a satellite on a circular orbit, an ILR-like resonance dominates the heating and this heating results in continuous satellite mass loss. We estimate the requirements for simulations to achieve these dynamics using perturbation theory. Both resonant shocks and resonant torques affect satellites on eccentric orbits. We demonstrate that satellite mass loss is an outside-in process in energy space; a satellite's stars and gas are thus protected by their own halo against tidal stripping. We simulate the evolution of a halo similar to the Large Magellanic Cloud (LMC) in our Galactic dark matter halo and conclude that the LMC stars have not yet been stripped. Finally, we present a simple algorithm for estimating the evolution of satellite mass that includes both shock heating and resonant torques.

Jun-Hwan Choi; Martin D. Weinberg; Neal Katz
2009-08-17

343

SEQUOIA 2000 METADATA SCHEMA FOR SATELLITE IMAGES Jean T. Anderson and Michael Stonebraker

  Computer Technologies and Information Sciences Websites

Summary: SEQUOIA 2000 METADATA SCHEMA FOR SATELLITE IMAGES Jean T. Anderson and Michael Stonebraker EECS. This paper focuses on the metadata schema for digital satellite images. We examine how satellite metadata on the metadata schema being developed to manage satellite images. Section 2 looks at satellite data

California at Irvine, University of

344

OPTIMAL DESPIN OF A TUMBLING SATELLITE WITH AN ARBITRARY THRUSTER CONFIGURATION, INERTIA MATRIX,

  Engineering Websites

Summary: 1 OPTIMAL DESPIN OF A TUMBLING SATELLITE WITH AN ARBITRARY THRUSTER CONFIGURATION, INERTIA MATRIX to despin a tumbling satellite with known, but arbitrary thruster configuration, inertia matrix, and cost-orbit servicing of satellites is how to cap- ture and despin a satellite that may be tumbling. A satellite can


345

ISCTM/MJFF Satellite Meeting 22 February/S Murphy 1

  Mathematics Websites

Summary: ISCTM/MJFF Satellite Meeting 22 February/S Murphy 1 #12;ISCTM/MJFF Satellite Meeting 22 February/MJFF Satellite Meeting 22 February/S Murphy 3 #12;ISCTM/MJFF Satellite Meeting 22 February/S Murphy 4 #12;ISCTM/MJFF Satellite Meeting 22 February/S Murphy 5 First review the general principles behind pilot studies. The key

Murphy, Susan A.

346

STRUCTURAL HIGH-RESOLUTION SATELLITE IMAGE INDEXING Gui-Song Xia1

  Physics Websites

Summary: STRUCTURAL HIGH-RESOLUTION SATELLITE IMAGE INDEXING Gui-Song Xia1 , Wen Yang2 , Julie Delon1 , Yann: retrieval and classification, high-resolution satellite image, structure, texture ABSTRACT: Satellite images-resolution satellite images. We suggest a satellite image indexing method relying on topographic maps and a shape

Paris-Sud XI, Université de

347

Fast object detection for use onboard satellites

  CERN Preprints

Summary: We propose an object detection algorithm which is efficient and fast enough to be used in (almost) real time with the limited computer capacities onboard satellites. For stars below the saturation limit of the CCD detectors it is based on a four neighbourhood local maximum criterion in order to find the centre of a stellar image. For saturated stars it is based on the assumption that the image is increasing monotonically towards the centre in the unsaturated part of the image. The algorithm also calculates approximate stellar magnitudes and efficiently rejects most of the cosmics which would otherwise lead to a large number of false detections. The quality of the algorithm was evaluated with the help of a large set of simulated data for the DIVA satellite mission; different assumptions were made for the noise level, and the presence of cosmics or for a variable sky background. We could show that our algorithm fulfills the requirements for DIVA; only in the case of simulated images which included the bright ga...

Bange, M; Biermann, M; Kaempke, T; Scholz, R D; Bange, Martin; Jordan, Stefan; Biermann, Michael; Kaempke, Thomas
2002-01-01

348

The Big Occulting Steerable Satellite (BOSS)

  Astrophysics (arXiv)

Summary: Natural (such as lunar) occultations have long been used to study sources on small angular scales, while coronographs have been used to study high contrast sources. We propose launching the Big Occulting Steerable Satellite (BOSS), a large steerable occulting satellite to combine both of these techniques. BOSS will have several advantages over standard occulting bodies. BOSS would block all but about 4e-5 of the light at 1 micron in the region of interest around the star for planet detections. Because the occultation occurs outside the telescope, scattering inside the telescope does not degrade this performance. BOSS could be combined with a space telescope at the Earth-Sun L2 point to yield very long integration times, in excess of 3000 seconds. If placed in Earth orbit, integration times of 160--1600 seconds can be achieved from most major telescope sites for objects in over 90% of the sky. Applications for BOSS include direct imaging of planets around nearby stars. Planets separated by as little as 0.1--0.25 arcseconds from the star they orbit could be seen down to a relative intensity as little as 1e-9 around a magnitude 8 (or brighter) star. Other applications include ultra-high resolution imaging of compound sources, such as microlensed stars and quasars, down to a resolution as little as 0.1 milliarcseconds.

Craig J. Copi; Glenn D. Starkman
1999-04-29

349

Satellite dynamics on the Laplace surface

  CERN Preprints

Summary: The orbital dynamics of most planetary satellites is governed by the quadrupole moment from the equatorial bulge of the host planet and the tidal field from the Sun. On the Laplace surface, the long-term orbital evolution driven by the combined effects of these forces is zero, so that orbits have a fixed orientation and shape. The "classical" Laplace surface is defined for circular orbits, and coincides with the planet's equator at small planetocentric distances and with its orbital plane at large distances. A dissipative circumplanetary disk should settle to this surface, and hence satellites formed from such a disk are likely to orbit in or near the classical Laplace surface. This paper studies the properties of Laplace surfaces. Our principal results are: (i) if the planetary obliquity exceeds 68.875 deg there is a range of semimajor axes in which the classical Laplace surface is unstable; (ii) at some obliquities and planetocentric distances there is a distinct Laplace surface consisting of nested eccentr...

Tremaine, Scott; Namouni, Fathi
2008-01-01

350

Satellite dynamics on the Laplace surface

  Astrophysics (arXiv)

Summary: The orbital dynamics of most planetary satellites is governed by the quadrupole moment from the equatorial bulge of the host planet and the tidal field from the Sun. On the Laplace surface, the long-term orbital evolution driven by the combined effects of these forces is zero, so that orbits have a fixed orientation and shape. The "classical" Laplace surface is defined for circular orbits, and coincides with the planet's equator at small planetocentric distances and with its orbital plane at large distances. A dissipative circumplanetary disk should settle to this surface, and hence satellites formed from such a disk are likely to orbit in or near the classical Laplace surface. This paper studies the properties of Laplace surfaces. Our principal results are: (i) if the planetary obliquity exceeds 68.875 deg there is a range of semimajor axes in which the classical Laplace surface is unstable; (ii) at some obliquities and planetocentric distances there is a distinct Laplace surface consisting of nested eccentric orbits, which bifurcates from the classical Laplace surface at the point where instability sets in; (iii) there is also a "polar" Laplace surface perpendicular to the line of nodes of the planetary equator on the planetary orbit; (iv) for circular orbits, the polar Laplace surface is stable at small planetocentric distances and unstable at large distances; (v) at the onset of instability this polar Laplace surface bifurcates into two polar Laplace surfaces composed of nested eccentric orbits.

Scott Tremaine; Jihad Touma; Fathi Namouni
2008-09-01

351

Fast object detection for use onboard satellites

  Astrophysics (arXiv)

Summary: We propose an object detection algorithm which is efficient and fast enough to be used in (almost) real time with the limited computer capacities onboard satellites. For stars below the saturation limit of the CCD detectors it is based on a four neighbourhood local maximum criterion in order to find the centre of a stellar image. For saturated stars it is based on the assumption that the image is increasing monotonically towards the centre in the unsaturated part of the image. The algorithm also calculates approximate stellar magnitudes and efficiently rejects most of the cosmics which would otherwise lead to a large number of false detections. The quality of the algorithm was evaluated with the help of a large set of simulated data for the DIVA satellite mission; different assumptions were made for the noise level, and the presence of cosmics or for a variable sky background. We could show that our algorithm fulfills the requirements for DIVA; only in the case of simulated images which included the bright galaxy M31 some fainter stars could not be detected in the galaxy's vicinity. Since stellar images contain large areas without any stars, we propose an additional block-skipping algorithm which can be coded on special-purpose hardware.

Martin Bange; Stefan Jordan; Michael Biermann; Thomas Kaempke; R alf-Dieter Scholz
2003-01-30

352

Evaluation of Long-Term Cloud-Resolving Model Simulations Using Satellite Radiance Observations and Multifrequency Satellite Simulators

  Physics Websites

Summary: This paper proposes a methodology known as the Tropical Rainfall Measuring Mission (TRMM) Triple- Sensor statistics of multisensor radiance and backscattering signals observed from the TRMM satellite. Specifically

Masunaga, Hirohiko

353

Temporal disaggregation of satellite-derived precipitation estimatesHydrology and Earth System Sciences, 5(1), 2738 (2001) EGS Temporal disaggregation of satellite-derived monthly precipitation

  Physics Websites

Summary: 27 Temporal disaggregation of satellite-derived precipitation estimatesHydrology and Earth System Sciences, 5(1), 27­38 (2001) © EGS Temporal disaggregation of satellite-derived monthly precipitation and low earth-orbit satellites. However, revisit patterns of polar-orbiting satellites and the need

Paris-Sud XI, Université de
2001-01-01

354

Adaptive Thermal Modeling Architecture for Small Satellite Applications

  Engineering Websites

Summary: Adaptive Thermal Modeling Architecture for Small Satellite Applications 2Lt. John Anger Richmond Architecture for Small Satellite Applications 2Lt. John Anger Richmond, USAF Colonel John Keesee, USAF Retired May 2010 SSL # 4-10 This work is based on the unaltered text of the thesis by 2Lt. John Anger Richmond


355

Motion properties of satellites around external spiral galaxies

  Astrophysics (arXiv)

Summary: We are analyzing a sample of closeby galaxy systems, each comprising a bright isolated spiral and its satellites. We find an excess (56%) of prograde satellites over retrograde, which basically holds for all angular displacements from the primary major axis. Monte Carlo simulations show that interlopers and mixing systems at different distances in the sample should not affect porcentages sensibly.

M. Azzaro; F. Prada; C. M. Gutiérrez
2003-10-17

356

Modelling Uncertainty in Satellite Derived Land Edward Cripps

  Mathematics Websites

Summary: Modelling Uncertainty in Satellite Derived Land Cover Maps Edward Cripps Anthony O'Hagan Tristan Quaife Clive Anderson March 24, 2009 Abstract Maps of land cover, derived from satellite observation, the true land cover category at a given site may differ from the category assigned in the map

O'Hagan, Tony

357

Using satellite data for mapping offshore wind resources and wakes

  Multidisciplinary Databases and Resources Websites

Summary: SectionRadarCrossNormalized = Physics Ocean surface roughens by wind interaction: Capillary and short gravity waves are generated. More wind causes more steep waves causes higher backscatter. #12;1800 km 400 km 100 km ERS Envisat Quik;Conclusions · Satellite ocean wind from many satellites are used to calculate: mean wind speed, Weibull


358

VERY HIGH RESOLUTION SATELLITE IMAGES FOR PARAMETERIZATION OF

  Computer Technologies and Information Sciences Websites

Summary: were orthorectified. A tree crown detection algorithm, based on the marked point processes [6VERY HIGH RESOLUTION SATELLITE IMAGES FOR PARAMETERIZATION OF TREE-SCALE FOREST PROCESS-BASED MODEL (VHSR) satellite images provide interesting information for parameterizing tree-scale forest process-based

Boyer, Edmond

359

Observing ocean heat content using satellite gravity and altimetry

  Geosciences Websites

Summary: . Geophys. Res., 108(C2), 3031, doi:10.1029/2002JC001619, 2003. 1. Introduction [2] The exchange of heatObserving ocean heat content using satellite gravity and altimetry Steven R. Jayne1,2 and John M with satellite measurements of the Earth's time-varying gravity to give improved estimates of the ocean's heat

Jayne, Steven

360

CHANGES IN THE NIGHTTIME LANDSCAPES DERIVED BY SATELLITE Jon Mathieu

  Geosciences Websites

Summary: Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) data for analyzing cities boundaries and the their surrounding to derive the landscape. Doing this with the old analog DMSP data was a challenge. In this work we of the Defense Meteorological Satellite Program (DMSP), records useful data in the visible channel. Its

Wunderle, Stefan

361

International Symposium on Formal Methods 2012 Autonomy in Satellite Systems

  Engineering Websites

Summary: of the satellite the orbit is uniquely defined · Fixing an orbit o, the angular speed (v) is given by: · Orbital currently in orbit: 3,000 · Speed of a satellite in Geostationary Orbit ~ 11,000 Kmph · Radio delay system: 2D rectangle with "wrap-around" transitions Distance properties mapped to predicates on angular

Liberzon, Daniel

362

Performance Modelling of TCP Enhancements in Terrestrial-Satellite Hybrid

  Engineering Websites

Summary: 1 Performance Modelling of TCP Enhancements in Terrestrial-Satellite Hybrid Networks Jing Zhu Abstract In this paper, we focus on the performance of TCP enhancements for a hybrid terrestrial- satellite network. Compared to other network scenarios for which many models of TCP were proposed in the literature

Roy, Sumit

363

Physical aspects to consider in radiometric calibration of satellite images

  CERN Preprints

Summary: It does a revision about the physical principles involved in digital processing of satellite images, more specifically in radiometric calibration of them. It shows a conceptual description of the interaction between radiation and atmosphere and radiation and soil in order to help the reader understand in more detail which means the information contained in satellite images.

Delgado-Correal, Camilo
2012-01-01

364

Testing General Relativity and gravitational physics using the LARES satellite

  General Relativity & Quantum Cosmology (arXiv)

Summary: The discovery of the accelerating expansion of the Universe, thought to be driven by a mysterious form of `dark energy' constituting most of the Universe, has further revived the interest in testing Einstein's theory of General Relativity. At the very foundation of Einstein's theory is the geodesic motion of a small, structureless test-particle. Depending on the physical context, a star, planet or satellite can behave very nearly like a test-particle, so geodesic motion is used to calculate the advance of the perihelion of a planet's orbit, the dynamics of a binary pulsar system and of an Earth orbiting satellite. Verifying geodesic motion is then a test of paramount importance to General Relativity and other theories of fundamental physics. On the basis of the first few months of observations of the recently launched satellite LARES, its orbit shows the best agreement of any satellite with the test-particle motion predicted by General Relativity. That is, after modelling its known non-gravitational perturbations, the LARES orbit shows the smallest deviations from geodesic motion of any artificial satellite. LARES-type satellites can thus be used for accurate measurements and for tests of gravitational and fundamental physics. Already with only a few months of observation, LARES provides smaller scatter in the determination of several low-degree geopotential coefficients (Earth gravitational deviations from sphericity) than available from observations of any other satellite or combination of satellites.

Ignazio Ciufolini; Antonio Paolozzi; Erricos Pavlis; John Ries; Vahe Gurzadyan; Rolf Koenig; Richard Matzner; Roger Penrose; Giampiero Sindoni
2012-11-06

365

Quantifying Offshore Wind Resources from Satellite Wind Maps

  Environmental Sciences and Ecology Websites

Summary: the spatial extent of the wake behind large offshore wind farms. Copyright © 2006 John Wiley & Sons, LtdQuantifying Offshore Wind Resources from Satellite Wind Maps: Study Area the North Sea C. B National Laboratory, Roskilde, Denmark Offshore wind resources are quantified from satellite synthetic

Pryor, Sara C.

366

Digital Video Broadcasting By Satellite Matthew C. Valenti

  Computer Technologies and Information Sciences Websites

Summary: Providers Digital Satellite Television in the United States DirecTV Spinoff of Hughes Network Systems. Began Network Systems. DirecTV. M.C. Valenti ( Lane Department of Computer Science and Electrical Engineering West Virginia UniverLDPC Codes Apr. 2, 2012 2 / 41 #12;Outline 1 Satellite Television Standards 2 DVB

Valenti, Matthew C.

367

Modelling the core field using 21st century satellite observations

  Geosciences Websites

Summary: High precision magnetic measurements from the Oersted, CHAMP and SAC-C satellites are now available of anisotropic errors due to the satellite measurement setup, and an attempt is made to take account of latitudinal variations in errors due to unmodelled ring current fluctations and auroral excitation. A L1

Finlay, Christopher

368

Improving TCP performance in mobile satellite IP communications

  Computer Technologies and Information Sciences Websites

Summary: (TCP) Motivation for TCP performance improvement Mobile satellite services risks uncertainties ethics: "everywhere computing: a human-centric system" quality of service (QoS) is maintained for network services design issues arise in satellite transmission circuits using TCP as primary transport protocol #12;June

Trajkovic, Ljiljana

369

Design, Implementation and Control of a Sparse Aperture Imaging Satellite

  Engineering Websites

Summary: Design, Implementation and Control of a Sparse Aperture Imaging Satellite by Soon-Jo Chung B;2 #12;3 Design, Implementation and Control of a Sparse Aperture Imaging Satellite by SOON-JO CHUNG, the diameter size of primary mirrors for space telescopes is limited by the volume and mass constraints


370

Satellite Link Layer Performance Using Two Copy SR-ARQ

  Engineering Websites

Summary: satellite channels (LMSC) at higher frequencies such as K or EHF band, where shadowing is the primary impediment to reliable data transmis- sion. Compared with short-term multipath fading, shadowing is char satellite channel at K or EHF bands is shadowing due to blockage rather than multipath fading. In such cases

Roy, Sumit

371

A DESIGN FOR SATELLITE GROUND STATION RECEIVER AUTOCONFIGURATION

  Engineering Websites

Summary: A DESIGN FOR SATELLITE GROUND STATION RECEIVER AUTOCONFIGURATION Phillip De Leon, Qingsong Wang a receiver design for satellite ground station use which can demodulate a waveform without specific knowledge, ground station receiver, autoconfiguration, self-configuration 1. INTRODUCTION Users of NASA's Space

De Leon, Phillip

372

ORIGINAL PAPER Comparing land surface phenology derived from satellite

  Environmental Sciences and Ecology Websites

Summary: optical-infrared (IR) sensors, have provided direct LSP mea- sures of the phenological state of vegetation from satellite optical-IR re- mote sensing is constrained over many areas by clouds and M. O. JonesORIGINAL PAPER Comparing land surface phenology derived from satellite and GPS network microwave

Montana, University of

373

Jupiter's Outer Satellites and Trojans David C. Jewitt

  Physics Websites

Summary: 12 Jupiter's Outer Satellites and Trojans David C. Jewitt Institute for Astronomy, University Institute 12.1 INTRODUCTION Jupiter's irregular satellites possess large, eccentric and highly inclined and the Trojans (the latter co-orbiting the Sun leading and trailing Jupiter by 60 deg). However, there is reason

Jewitt, David C.

374

Jupiter's Outer Satellites and Trojans David C. Jewitt

  Physics Websites

Summary: 12 Jupiter's Outer Satellites and Trojans David C. Jewitt Institute for Astronomy, University Institute 12.1 INTRODUCTION Jupiter's irregular satellites possess large, eccentric and highly inclined and the Trojans (the latter co-orbiting the Sun leading and trailing Jupiter by 60 ). However, there is reason

Jewitt, David C.

375

Monitoring drying up of Urmia lake satellite altimetry

  Geosciences Websites

Summary: Monitoring drying up of Urmia lake with satellite altimetry Sh. Roohi (shirzad Validation Analysis and conclusion Monitoring drying up of Urmia lake with satellite altimetry 1 #12;Introduction Urmia lake Geography Chemistry Ecology Main inflow rivers Monitoring drying up of Urmia lake

Stuttgart, Universität

376

Stability of Satellites in Closely Packed Planetary Systems

  CERN Preprints

Summary: We perform numerical integrations of four-body (star, planet, planet, satellite) systems to investigate the stability of satellites in planetary Systems with Tightly-packed Inner Planets (STIPs). We find that the majority of closely-spaced stable two-planet systems can stably support satellites across a range of parameter-space which is only slightly decreased compared to that seen for the single-planet case. In particular, circular prograde satellites remain stable out to $\\sim 0.4 R_H$ (where $R_H$ is the Hill Radius) as opposed to $\\sim 0.5 R_H$ in the single-planet case. A similarly small restriction in the stable parameter-space for retrograde satellites is observed, where planetary close approaches in the range 2.5 to 4.5 mutual Hill radii destabilize most satellites orbits only if $a\\sim 0.65 R_H$. In very close planetary pairs (e.g. the 12:11 resonance) the addition of a satellite frequently destabilizes the entire system, causing extreme close-approaches and the loss of satellites over a range of cir...

Payne, Matthew J; Holman, Matthew J; Perets, Hagai B
2013-01-01

377

Asteroid 2014 OL339: yet another Earth quasi-satellite

  CERN Preprints

Summary: Our planet has one permanently bound satellite -the Moon-, a likely large number of mini-moons or transient irregular natural satellites, and three temporary natural retrograde satellites or quasi-satellites. These quasi-moons -(164207) 2004 GU9, (277810) 2006 FV35 and 2013 LX28- are unbound companions to the Earth. The orbital evolution of quasi-satellites may transform them into temporarily bound satellites of our planet. Here, we study the dynamical evolution of the recently discovered Aten asteroid 2014 OL339 to show that it is currently following a quasi-satellite orbit with respect to the Earth. This episode started at least about 775 yr ago and it will end 165 yr from now. The orbit of this object is quite chaotic and together with 164207 are the most unstable of the known Earth quasi-satellites. This group of minor bodies is, dynamically speaking, very heterogeneous but three of them exhibit Kozai-like dynamics: the argument of perihelion of 164207 oscillates around -90 degrees, the one of 277810 libr...

Marcos, C de la Fuente
2014-01-01

378

NASA ACTS SATELLITE: A DISASTER RECOVERY TEST Dr. Hans Kruse

  Engineering Websites

Summary: NASA ACTS SATELLITE: A DISASTER RECOVERY TEST Dr. Hans Kruse School of Communications Systems In September 1993, NASA launched its long- awaited Advanced Communication Technology (ACTS) satellite. ACTS links. The ACTS Disaster Recovery Project was designed to test the Bank's ability to by

Kruse, Hans

379

Distributed Geo-rectification of Satellite Images using Grid Computing

  Computer Technologies and Information Sciences Websites

Summary: include wrapping satellite positional data to compensate the earth curvature, and consist of several steps by the earth's curvature in raw satellite images. It establishes the image in the correct spatial location], specifically the geo-rectification of earth images. Geo-rectification is the correction of skew caused

Teo, Yong-Meng

380

First satellite observations of lower tropospheric ammonia and methanol

  Geosciences Websites

Summary: First satellite observations of lower tropospheric ammonia and methanol Reinhard Beer,1 Mark W) and methanol (CH3OH), well above the normal background levels. This is the first time that these molecules have. Citation: Beer, R., et al. (2008), First satellite observations of lower tropospheric ammonia and methanol


381

A Satellite Survey Cloud Cover and Water Vapor

  Physics Websites

Summary: A Satellite Survey of Cloud Cover and Water Vapor in Northern Chile A study conducted for: Cerro, the frequency of occurrence of these conditions were determined from satellite observations of cloud cover brightness temperature to UTH 10 4.3 Computation of precipitable water vapor 11 4.4 Cloud detection


382

Satellite Eye for Galathea 3 Annual Report 2007

  Multidisciplinary Databases and Resources Websites

Summary: observations and through collaboration with many Galathea 3 research projects educational material for upper secondary schools were being prepared. A total of 41 educational projects were being developed. Most the Satellite Eye team jointly with Nature & science prepared an educational film `Satellite Eye ­ Galathea 3


383

Title: Worldview 2 Satellite Image of York University Data Creator /

  Computer Technologies and Information Sciences Websites

Summary: Title: Worldview 2 Satellite Image of York University Data Creator / Copyright Owner: Digital Globe Publisher: Digital Globe Edition: N/A Versions: N/A Publication Date: 2013 Coverage Date(s): July 25, 2012 Updates: N/A Abstract: Worldview 2 Satellite Image: Orthorectified image of York University Keele campus


384

A Region Void of Irregular Satellites Around Jupiter

  Astrophysics (arXiv)

Summary: An interesting feature of the giant planets of our solar system is the existence of regions around these objects where no irregular satellites are observed. Surveys have shown that, around Jupiter, such a region extends from the outermost regular satellite Callisto, to the vicinity of Themisto, the innermost irregular satellite. To understand the reason for the existence of such a satellite-void region, we have studied the dynamical evolution of Jovian irregulars by numerically integrating the orbits of several hundred test particles, distributed in a region between 30 and 80 Jupiter-radii, for different values of their semimajor axes, orbital eccentricities, and inclinations. As expected, our simulations indicate that objects in or close to the influence zones of the Galilean satellites become unstable because of interactions with Ganymede and Callisto. However, these perturbations cannot account for the lack of irregular satellites in the entire region between Callisto and Themisto. It is suggested that at distances between 60 and 80 Jupiter-radii, Ganymede and Callisto may have long-term perturbative effects, which may require the integrations to be extended to times much longer than 10 Myr. The interactions of irregular satellites with protosatellites of Jupiter at the time of the formation of Jovian regulars may also be a destabilizing mechanism in this region. We present the results of our numerical simulations and discuss their applicability to similar satellite void-regions around other giant planets.

N. Haghighipour; D. Jewitt
2008-05-24

385

Resonant Thickening of Disks by Small Satellite Galaxies

  Astrophysics (arXiv)

Summary: We study the vertical heating and thickening of galaxy disks due to accretion of small satellites. Our simulations are restricted to axial symmetry, which largely eliminates numerical evolution of the target galaxy but requires the trajectory of the satellite to be along the symmetry axis of the target. We find that direct heating of disk stars by the satellite is not important because the satellite's gravitational perturbation has little power at frequencies resonant with the vertical stellar orbits. The satellite does little damage to the disk until its decaying orbit resonantly excites large-scale disk bending waves. Bending waves can damp through dynamical friction from the halo or internal wave-particle resonances; we find that wave-particle resonances dominate the damping. The principal vertical heating mechanism is therefore dissipation of bending waves at resonances with stellar orbits in the disk. Energy can thus be deposited some distance from the point of impact of the satellite. The net heating from a tightly bound satellite can be substantial, but satellites that are tidally disrupted before they are able to excite bending waves do not thicken the disk.

J. A. Sellwood; Robert W. Nelson; Scott Tremaine
1998-05-12

386

Rotational spectroscopy of S2O: vibrational satellites, 33

  Physics Websites

Summary: Rotational spectroscopy of S2O: vibrational satellites, 33 S isotopomers, and the submillimeter structure, vibrational satellites PACS: Preprint submitted to Elsevier Science 23 February 2006 #12]. A microwave study of S2 18 O v2 = 0, 1 has also been reported [4] as well as diode laser investigations

Thorwirth, Sven

387

Research Article The Effect of Lunarlike Satellites on the Orbital

  Geosciences Websites

Summary: Research Article The Effect of Lunarlike Satellites on the Orbital Infrared Light Curves of Earth the influence of lunarlike satellites on the infrared orbital light curves of Earth-analog extrasolar planets orbit. We used an energy balance model to calculate disk-averaged infrared (bolometric) fluxes from

Moskovitz, Nicholas

388

On the scarcity of Magellanic Cloud-like satellites

  CERN Preprints

Summary: We have used H alpha narrow-band imaging to search for star-forming satellite galaxies around 143 luminous spiral galaxies, with the goal of quantifying the frequency of occurrence of satellites resembling the Magellanic Clouds, around galaxies comparable to the Milky Way. For two-thirds of the central galaxies, no star-forming satellites are found, down to luminosities and star-formation rates well below those of the Magellanic Clouds. A total of 62 satellites is found, associated with 47 of the central galaxies searched. The R-band magnitude difference between central galaxies and their satellites has a median value of 4.6 mag, and a maximum of 10.2 mag. The mean projected separation of the satellites from their central galaxies is 81 kpc, or 98 kpc for systems beyond 30 Mpc. Thus star-forming satellites are quite rare, and the Milky Way is unusual both for the luminosity and the proximity of its two brightest satellites. We also find that the Clouds themselves are unusual in that they appear to form a boun...

James, Phil A
2010-01-01

389

Analysis of sampling behavior of candidate SWOT satellite orbits

  Geosciences Websites

Summary: sides of the orbital track. Look angles are limited to less than 4.5 providing a 120 km wide swathAnalysis of sampling behavior of candidate SWOT satellite orbits Sh. Roohi, N. Sneeuw Institute of Geodesy, University of Stuttgart, Germany Abstract Current satellite altimetry can not monitor global

Stuttgart, Universität

390

Satellite Measurements Reveal Persistent Small-Scale Features in

  Geosciences Websites

Summary: Satellite Measurements Reveal Persistent Small-Scale Features in Ocean Winds Dudley B. Chelton,1-resolution measurements of near-surface wind speed and direction over the global ocean from the QuikSCAT satellite radar and thermodynamically important curl and diver- gence of the wind stress. Air-sea interaction over sea surface

Kurapov, Alexander

391

The dynamics of satellite disruption in cold dark matter haloes

  CERN Preprints

Summary: We investigate the physical mechanisms of tidal heating and satellite disruption in cold dark matter host haloes using N-body simulations based on cosmological initial conditions. We show the importance of resonant shocks and resonant torques with the host halo to satellite heating. A resonant shock (torque) couples the radial (tangential) motion of a satellite in its orbit to its phase space. For a satellite on a circular orbit, an ILR-like resonance dominates the heating and this heating results in continuous satellite mass loss. We estimate the requirements for simulations to achieve these dynamics using perturbation theory. Both resonant shocks and resonant torques affect satellites on eccentric orbits. We demonstrate that satellite mass loss is an outside-in process in energy space; a satellite's stars and gas are thus protected by their own halo against tidal stripping. We simulate the evolution of a halo similar to the Large Magellanic Cloud (LMC) in our Galactic dark matter halo and conclude that the ...

Choi, Jun-Hwan; Katz, Neal
2008-01-01

392

SPICE Testbed: A DTN Testbed for Satellite and Space Communications

  Computer Technologies and Information Sciences Websites

Summary: SPICE Testbed: A DTN Testbed for Satellite and Space Communications Ioannis Komnios, Ioannis SPICE testbed, a state-of-the-art Delay Tolerant Networking testbed for satellite and space of underlying and overlying protocols. SPICE testbed is equipped with specialised hardware components

Tsaoussidis, Vassilis

393

Effects of Rain Attenuation on Satellite Video Transmission

  Computer Technologies and Information Sciences Websites

Summary: Effects of Rain Attenuation on Satellite Video Transmission Yee Hui Lee and Stefan Winkler Nanyang, email: stefan.winkler@adsc.com.sg Abstract--Heavy convective rain events are often experienced] caused by rain or cloud cover. Poor link conditions can lead to signal outage. Satellite service

Winkler, Stefan

394

FOP Is a Centriolar Satellite Protein Involved in Ciliogenesis

  Biology and Medicine Websites

Summary: BBS4. As for BBS4, FOP localization to satellites is cell cycle dependent, with few satellites labeled in G1, when FOP protein levels are lowest, and most labeled in G2. FOP- FGFR1, an oncogenic fusion://www.arcsfoundation.org), and NIH Grant GM52022 to T.S. The funders had no role in study design, data collection and analysis

Stearns, Tim

395

A NOVEL DIMENSIONING METHOD FOR HIGH THROUGHPUT SATELLITE DESIGN

  Physics Websites

Summary: A NOVEL DIMENSIONING METHOD FOR HIGH THROUGHPUT SATELLITE DESIGN Dimitri Serrano-Velarde Eutelsat@eutelsat.com Georges Rodriguez-Guisantes TELECOM ParisTech, Communications and Electronics, 46, rue Barrault, 75634 describes a novel methodology for the dimensioning of a Ka-Band high throughput satellite for broadband

Paris-Sud XI, Université de

396

On the central configurations of the coorbital satellite problem

  Mathematics Websites

Summary: On the central configurations of the coorbital satellite problem Josep M. Cors 1 Jaume Llibre 2 Merc`e Oll'e 3 Abstract In this communication we study the central configurations of the coorbital satellite problem --also called 1 +n body problem--, that is, we study the central configurations of a large

Politècnica de Catalunya, Universitat

397

Bandwidth Allocation for IP Traffic Over Satellite Links

  Computer Technologies and Information Sciences Websites

Summary: provisioning is discussed. Index terms: satellite communications, ground terminals, TCP/IP, QoS, qualityBandwidth Allocation for IP Traffic Over Satellite Links Claude Bélisle, Peter Andreadis, Steve Bernier, François Lévesque, and Michel Barbeau Communications Research Centre Canada 3701 Carling Avenue

Barbeau, Michel

398

Adaptive Beamforming in Mobile, Massively Multiuser Satellite Communications: A System

  Engineering Websites

Summary: Adaptive Beamforming in Mobile, Massively Multiuser Satellite Communications: A System Perspective Xiao Lei, Laura Cottatellucci, Samah A. M. Ghanem Mobile Communications Department, Eurecom, France Email: {xiao.lei; laura.cottatellucci; samah.ghanem}@eurecom.fr Abstract--We consider a Mobile Satellite

Gesbert, David

399

Cyclone Global Navigation Satellite System (CYGNSS) Mission Overview

  Engineering Websites

Summary: _Handout_B The CYGNSS mission is comprised of 8 Low Earth Orbiting (LEO) spacecraft (S/C) that receive both direct-resolutionwindfieldimageryofTCgenesis,intensificationanddecay. GPS satellites CYGNSS Observatories Primary Objectives: · Measure ocean surface wind speed in all Global Navigation Satellite System (CYGNSS) Mission Timeline Delay Doppler Mapping Instrument (DDMI)Observatory

Eustice, Ryan

400

Geosynchronous satellite maneuver detection and orbit recovery using ground based optical tracking

  MIT - DSpace

Summary: Geosynchronous satellite orbit maintenance is a very important issue. Satellites maneuver frequently requiring the ability to detect unknown maneuvers for target satellites and quickly recover an accurate orbit. This study ...

Aaron, Benjamin S. (Benjamin Samuel)
2006-01-01

401

Climatology and comparison study of stratosphere and lower mesosphere temperatures using satellite and reanalysis data sets

  University of California eScholarship Repository

Summary: temperature structure generated by the GPS RO, satellite andSATELLITE AND REANALYSIS DATA SETS Figure 10. Latitudinal structurestructures by GPS (CHAMP+COSMIC) with reanalysis data sets (JRA-25, GEOS5 and METO) and satellite

Madhavi, G. N.; Kishore, P.; Rao, S. V. B.; Velicogna, I.; Sivakumar, V.
2013-01-01

402

The relationship between the spectral diversity of satellite imagery, habitat heterogeneity, and plant species richness

  Environmental Sciences and Ecology Websites

Summary: measure of the relationship between the spectral diversity of satellite imagery, habitat heterogeneityThe relationship between the spectral diversity of satellite imagery, habitat heterogeneity multispectral satellite image, we examined 168 metrics of spectral diversity as potential indicators of those


403

NOAA Technical Report NESDIS 143 NOAA Coral Reef Watch 50 km Satellite Sea Surface

  Environmental Sciences and Ecology Websites

Summary: NOAA Technical Report NESDIS 143 NOAA Coral Reef Watch 50 km Satellite Sea Surface Temperature OF COMMERCE National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service #12;NOAA TECHNICAL REPORTS National Environmental Satellite, Data, and Information Service


404

Welcome from the CIOSS Director The Cooperative Institute for Oceanographic Satellite Studies (CIOSS) was

  Geosciences Websites

Summary: Welcome from the CIOSS Director The Cooperative Institute for Oceanographic Satellite Studies at the NESDIS STAR Satellite Oceanography and Climatology Division (SOCD) to enhance and improve the use of satellite remote sensing for oceanographic research, operational applications, and education

Kurapov, Alexander

405

Evaluation of mesoscale convective systems in South America using multiple satellite products and an objectbased approach

  Geosciences Websites

Summary: Evaluation of mesoscale convective systems in South America using multiple satellite products satellite precipitation products: Tropical Rainfall Measurement Mission (TRMM), Climate Prediction Center of all satellite products. Errors in the spatial location of the systems influenced the magnitude

Ebert, Beth

406

Development of Satellite Remote Sensing Techniques for Quantifying Volcanic Ash Cloud Properties

  Environmental Sciences and Ecology Websites

Summary: Development of Satellite Remote Sensing Techniques for Quantifying Volcanic Ash Cloud Properties, Professor, Atmospheric and Oceanic Sciences Kurt Feigl, Professor, Geoscience #12;i Development of Satellite approaches to automatically detect and characterize volcanic ash using satellite data are presented

Wisconsin at Madison, University of

407

THE GLOBAL IMPACT OF SATELLITE-DERIVED POLAR WINDS ON MODEL FORECASTS

  Environmental Sciences and Ecology Websites

Summary: THE GLOBAL IMPACT OF SATELLITE-DERIVED POLAR WINDS ON MODEL FORECASTS by David A. Santek........................................................................................................... 1 2. Satellite-derived winds algorithm........................................................................... 6 2.1 Geostationary satellite winds algorithm

Wisconsin at Madison, University of

408

Channel Estimation and Code Word Inference for Mobile Digital Satellite Broadcasting Reception

  Mathematics Websites

Summary: #12;Channel Estimation and Code Word Inference for Mobile Digital Satellite Broadcasting Reception reception of digital satellite broadcasting in a moving vehicle. According to some studies, the antennas sequences and diversity reception. Digital satellite broadcasting, however, does not transmit pilot

Ikeda, Shiro

409

FPGA Implementation of a Satellite Attitude Control using Variable Structure Control

  Computer Technologies and Information Sciences Websites

Summary: FPGA Implementation of a Satellite Attitude Control using Variable Structure Control Mokhtar Dept. of Electrical Engineering Effat University Jeddah Saudi Arabia Abstract-- Satellite control implementation of a Variable Structure Controller (VSC) for a satellite. Our implementation uses fixed point

Aboelaze, Mokhtar

410

Elisabeth FRAGNER: Prediction of satellite orbits with SLR (completed in May 1998)

  Geosciences Websites

Summary: Elisabeth FRAGNER: Prediction of satellite orbits with SLR (completed in May 1998) The modelling of artificial satellite orbits is nowadays often precondition for subsequent geodynamic represent the real distances, the eccentricitiy on the ground and at the satellite

Schuh, Harald

411

National Oceanic and Atmospheric Administration | NOAA Satellite and Information Service Two Orbits, One Mission

  Environmental Sciences and Ecology Websites

Summary: National Oceanic and Atmospheric Administration | NOAA Satellite and Information Service Two Orbits, One Mission Mission The NATIONAL ENVIRONMENTAL SATELLITE, DATA AND INFORMATION SERVICE (NESDIS) is dedicated to providing timely access to global environmental data from satellites and other sources


412

Managing diversity with handover to provide classes of service in satellite constellation networks

  Engineering Websites

Summary: 1 of 10 Managing diversity with handover to provide classes of service in satellite constellation satellite constellation network with intersatellite links (ISLs) presents unique properties, in providing locally separate ascending and descending network surfaces of interconnected satellites with which

Wood, Lloyd

413

AFFILIATIONS: AckermAn--Cooperative Institute for Meteorological Satellite Studies, and University of Wisconsin--

  Multidisciplinary Databases and Resources Websites

Summary: AFFILIATIONS: AckermAn--Cooperative Institute for Meteorological Satellite Studies, and University Satellite Studies, Madison, Wisconsin CORRESPONDING AUTHOR: Steven A. Ackerman, Department of Atmospheric Satellite Studies (CIMSS) was formed through a Memorandum of Understandingbetweenthe

Sheridan, Jennifer

414

Using QuickBird Sub-Metre Satellite Imagery for Implementation Monitoring and

  Renewable Energy Websites

Summary: Using QuickBird Sub-Metre Satellite Imagery for Implementation Monitoring and Effectiveness-Metre Satellite Imagery for Implementation Monitoring and Effectiveness Evaluation in Forestry. Research Section ............................................................................................................................................................................. 4 2.2 QuickBird Satellite


415

Mark S. Paese Deputy Assistant Administrator for Satellite and Information Services

  Environmental Sciences and Ecology Websites

Summary: Mark S. Paese Deputy Assistant Administrator for Satellite and Information Services Mark Paese serves as the Deputy Assistant Administrator for Satellite and Information Services, National Environmental Satellite, Data, and Information Service (NESDIS), National Oceanic and Atmospheric Administration


416

Data Gathering for Freeway Simulation Using Unintrusive Sensors and Satellite Telemetry*

  Energy Storage, Conversion and Utilization Websites

Summary: Data Gathering for Freeway Simulation Using Unintrusive Sensors and Satellite Telemetry* * 0 test results, and success- ful deployments of traffic sensor data retrieval via satellite communication, traffic sensors, sensor test- ing, satellite telemetry 1 Introduction A long running project (1996

Prevedouros, Panos D.

417

Multi-Attribute Tradespace Exploration for Survivability: Application to Satellite Radar

  Engineering Websites

Summary: issue for military space ­ Satellite radar architecture development Problem Statement *Richards, MMulti-Attribute Tradespace Exploration for Survivability: Application to Satellite Radar Matthew G · Problem Statement · Research Questions · Methodology Overview · Case Application: Satellite Radar

de Weck, Olivier L.

418

What Drives Spacecraft Innovation? A Quantitative Analysis of Communication Satellite History

  Engineering Websites

Summary: 1 What Drives Spacecraft Innovation? A Quantitative Analysis of Communication Satellite History of Communication Satellite History by Zoe Szajnfarber Submitted to the Department of Aeronautics tradeoffs associated with adopting this principle in the context of communication satellites

de Weck, Olivier L.

419

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING Int. J. Satell. Commun. Network. 2006; 24:261281

  Computer Technologies and Information Sciences Websites

Summary: INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING Int. J. Satell. Commun. Network: 10.1002/sat.841 Turbo-coded APSK modulations design for satellite broadband communications Riccardo phase shift keying (APSK) modulation with application to satellite broadband communications. APSK


420

Improved Explicit Congestion Notification for Satellite Networks Arjan Durresi*a

  Computer Technologies and Information Sciences Websites

Summary: of the greatest challenges before telecommunications industry in the 21st century. Satellite communicationImproved Explicit Congestion Notification for Satellite Networks Arjan Durresi*a , Mukundan University b Nayna Networks, Inc. ABSTRACT Due to the fundamental satellite system characteristics

Jain, Raj

421

Dark influences: imprints of dark satellites on dwarf galaxies

  CERN Preprints

Summary: In the context of the current $\\Lambda$CDM cosmological model small dark matter haloes are abundant and satellites of dwarf galaxies are expected to be predominantly dark. Since low mass galaxies have smaller baryon fractions interactions with these satellites may leave particularly dramatic imprints. We uncover the influence of the most massive of these dark satellites on disky dwarf galaxies and the possible dynamical and morphological transformations that result from these interactions. We use a suite of carefully set-up, controlled simulations of isolated dwarf galaxies. The primary dwarf galaxies have solely a stellar disk in the dark matter halo and the secundaries are completely devoid of baryons. We vary the disk mass, halo concentration, initial disk thickness and inclination of the satellite orbit. The disky dwarf galaxies are heated and disrupted due to the minor merger event, more extremely for higher satellite over disk mass ratios, and the morphology and kinematics are significantly altered. Mor...

Starkenburg, Tjitske K
2014-01-01

422

Asymptotic behavior of an elastic satellite with internal friction

  Mathematical Physics (arXiv)

Summary: We study the dynamics of an elastic body whose shape and position evolve due to the gravitational forces exerted by a pointlike planet. The main result is that, if all the deformations of the satellite dissipate some energy, then under a suitable nondegeneracy condition there are only three possible outcomes for the dynamics: (i) the orbit of the satellite is unbounded, (ii) the satellite falls on the planet, (iii) the satellite is captured in synchronous resonance i.e. its orbit is asymptotic to a motion in which the barycenter moves on a circular orbit, and the satellite moves rigidly, always showing the same face to the planet. The result is obtained by making use of LaSalle's invariance principle and by a careful kinematic analysis showing that energy stops dissipating only on synchronous orbits. We also use in quite an extensive way the fact that conservative elastodynamics is a Hamiltonian system invariant under the action of the rotation group.

Emanuele Haus; Dario Bambusi
2012-12-04

423

The Extended Shapes of Galactic Satellites

  CERN Preprints

Summary: We are exploring the extended stellar distributions of Galactic satellite galaxies and globular clusters. For seven objects studied thus far, the observed profile departs from a King function at large r, revealing a ``break population'' of stars. In our sample, the relative density of the ``break'' correlates to the inferred M/L of these objects. We discuss opposing hypotheses for this trend: (1) Higher M/L objects harbor more extended dark matter halos that support secondary, bound, stellar ``halos''. (2) The extended populations around dwarf spheroidals (and some clusters) consist of unbound, extratidal debris from their parent objects, which are undergoing various degrees of tidal disruption. In this scenario, higher M/L ratios reflect higher degrees of virial non-equilibrium in the parent objects, thus invalidating a precept underlying the use of core radial velocities to obtain masses.

Majewski, S R; Ostheimer, J C; Palma, C; Siegel, M H; Sohn, S; Westfall, K B; Patterson, R J; Frinchaboy, P M; Link, R
2001-01-01

424

The Extended Shapes of Galactic Satellites

  Astrophysics (arXiv)

Summary: We are exploring the extended stellar distributions of Galactic satellite galaxies and globular clusters. For seven objects studied thus far, the observed profile departs from a King function at large r, revealing a ``break population'' of stars. In our sample, the relative density of the ``break'' correlates to the inferred M/L of these objects. We discuss opposing hypotheses for this trend: (1) Higher M/L objects harbor more extended dark matter halos that support secondary, bound, stellar ``halos''. (2) The extended populations around dwarf spheroidals (and some clusters) consist of unbound, extratidal debris from their parent objects, which are undergoing various degrees of tidal disruption. In this scenario, higher M/L ratios reflect higher degrees of virial non-equilibrium in the parent objects, thus invalidating a precept underlying the use of core radial velocities to obtain masses.

S. R. Majewski; A. D. Forestell; J. C. Ostheimer; C. Palma; M. H. Siegel; S. Sohn; K. B. Westfall; R. J. Patterson; P. M. Frinchaboy; R. Link
2001-09-26

425

Symmetric Satellite Swarms and Choreographic Crystals

  CERN Preprints

Summary: In this paper, we introduce a natural dynamical analogue of crystalline order, which we call choreographic order. In an ordinary (static) crystal, a high degree of symmetry may be achieved through a careful arrangement of the fundamental repeated elements. In the dynamical analogue, a high degree of symmetry may be achieved by having the fundamental elements perform a carefully choreographed dance. For starters, we show how to construct and classify all symmetric satellite constellations. Then we explain how to generalize these ideas to construct and classify choreographic crystals more broadly. We introduce a quantity, called the "choreography" of a given configuration. We discuss the possibility that some (naturally occurring or artificial) many-body or condensed-matter systems may exhibit choreographic order, and suggest natural experimental signatures that could be used to identify and characterize such systems.

Boyle, Latham; Smith, Kendrick
2014-01-01

426

Symmetric Satellite Swarms and Choreographic Crystals

  Mathematical Physics (arXiv)

Summary: In this paper, we introduce a natural dynamical analogue of crystalline order, which we call choreographic order. In an ordinary (static) crystal, a high degree of symmetry may be achieved through a careful arrangement of the fundamental repeated elements. In the dynamical analogue, a high degree of symmetry may be achieved by having the fundamental elements perform a carefully choreographed dance. For starters, we show how to construct and classify all symmetric satellite constellations. Then we explain how to generalize these ideas to construct and classify choreographic crystals more broadly. We introduce a quantity, called the "choreography" of a given configuration. We discuss the possibility that some (naturally occurring or artificial) many-body or condensed-matter systems may exhibit choreographic order, and suggest natural experimental signatures that could be used to identify and characterize such systems.

Latham Boyle; Jun Yong Khoo; Kendrick Smith
2014-07-22

427

Submerged turbulence detection with optical satellites

  CERN Preprints

Summary: During fall periods in 2002, 2003 and 2004 three major oceanographic expeditions were carried out in Mamala Bay, Hawaii. These were part of the RASP Remote Anthropogenic Sensing Program. Ikonos and Quickbird optical satellite images of sea surface glint revealed ~100 m spectral anomalies in km^2 averaging patches in regions leading from the Honolulu Sand Island Municipal Outfall diffuser to distances up to 20 km. To determine the mechanisms behind this phenomenon, the RASP expeditions monitored the waters adjacent to the outfall with an array of hydrographic, optical and turbulence microstructure sensors in anomaly and ambient background regions. Drogue tracks and mean turbulence parameters for 2x10^4 microstructure patches were analyzed to understand complex turbulence, fossil turbulence and zombie turbulence near-vertical internal wave transport processes. The dominant mechanism appears to be generic to stratified natural fluids including planet and star atmospheres and is termed beamed zombie turbulence ma...

Gibson, Carl H; Bondur, Valery G; Leung, Pak T; Prandke, H; Vithanage, D
2007-01-01

428

Relative equilibria of four identical satellites

  Mathematical Physics (arXiv)

Summary: We consider the Newtonian 5-body problem in the plane, where 4 bodies have the same mass m, which is small compared to the mass M of the remaining body. We consider the (normalized) relative equilibria in this system, and follow them to the limit when m/M -> 0. In some cases two small bodies will coalesce at the limit. We call the other equilibria the relative equilibria of four separate identical satellites. We prove rigorously that there are only three such equilibria, all already known after the numerical researches in [SaY]. Our main contribution is to prove that any equilibrium configuration possesses a symmetry, a statement indicated in [CLO2] as the missing key to proving that there is no other equilibrium.

Alain Albouy; Yanning Fu
2009-02-18

429

Feasibility of satellite quantum key distribution

  Quantum Physics (arXiv)

Summary: In this paper we present a novel analysis of the feasibility of quantum key distribution between a LEO satellite and a ground station. First of all, we study signal propagation through a turbulent atmosphere for uplinks and downlinks, discussing the contribution of beam spreading and beam wandering. Then we introduce a model for the background noise of the channel during night-time and day-time, calculating the signal-to-noise ratio for different configurations. We also discuss the expected error-rate due to imperfect polarization-compensation in the channel. Finally, we calculate the expected key generation rate of a secure key for different configurations (uplink, downlink) and for different protocols (BB84 with and without decoy states, entanglement-based Ekert91 protocol).

Cristian Bonato; Andrea Tomaello; Vania Da Deppo; Giampiero Naletto; Paolo Villoresi
2009-05-12

430

Constraining supersymmetry from the satellite experiments

  HEP - Phenomenology (arXiv)

Summary: In this paper we study the detectability of $\\gamma$-rays from dark matter annihilation in the subhalos of the Milky Way by the satellite-based experiments, EGRET and GLAST. We work in the frame of supersymmetric extension of the standard model and assume the lightest neutralino being the dark matter particles. Based on the N-body simulation of the evolution of dark matter subhalos we first calculate the average intensity distribution of this new class of $\\gamma$-ray sources by neutralino annihilation. It is possible to detect these $\\gamma$-ray sources by EGRET and GLAST. Conversely, if these sources are not detected the nature of the dark matter particls will be constrained by these experiments, which, however, depending on the uncertainties of the subhalo profile.

Xiao-Jun Bi
2007-12-10

431

Downburst Prediction Applications of Meteorological Geostationary Satellites

  CERN Preprints

Summary: A suite of products has been developed and evaluated to assess hazards presented by convective storm downbursts derived from the current generation of Geostationary Operational Environmental Satellite (GOES) (13-15). The existing suite of GOES downburst prediction products employs the GOES sounder to calculate risk based on conceptual models of favorable environmental profiles for convective downburst generation. A diagnostic nowcasting product, the Microburst Windspeed Potential Index (MWPI), is designed to infer attributes of a favorable downburst environment: 1) the presence of large convective available potential energy (CAPE), and 2) the presence of a surface-based or elevated mixed layer with a steep temperature lapse rate and vertical relative humidity gradient. These conditions foster intense convective downdrafts upon the interaction of sub-saturated air in the elevated or sub-cloud mixed layer with the storm precipitation core. This paper provides an updated assessment of the MWPI algorithm, present...

Pryor, Kenneth L
2014-01-01

432

Properties of cluster satellites in hydrodynamical simulations

  Astrophysics (arXiv)

Summary: We analyze the dynamical and thermal evolution of dark matter and ICM in hydrodynamical Tree-SPH simulations of galaxy clusters. Starting from a sample of 17 high-resolution objects, with virial mass ranging from 3 10^{14} to 1.7 10^{15} M_sun, we follow the build-up of the systems in dark matter and hot gas through the repeated merging of satellites along their merging history trees. We measure the self-bound mass fraction of subhaloes as a function of time after the merging, estimate the satellite mean orbital properties as a function of the mass ratio with the main cluster at merging time, and study the evolution of their internal velocity dispersion, gas temperature and entropy as the substructure is disrupted by various dynamical processes, reaching eventually thermo-dynamic equilibrium in the gravitational potential of the main cluster. We model some relevant properties of subhalo orbits, as the time of the first pericentric and apocentric passages, and the typical distances and velocities at the corresponding times. This survival study can be used to interpret the dynamics of observed merging clusters; as an example we apply our results to the system 1E0657-56. We show that, in the light of our results, the most likely interpretation of the data for this cluster points to the merger of a small group with mass M\\approx 1 10^{13} M_sun with a massive cluster with M\\approx 1.3 10^{15} M_sun.

Giuseppe Tormen; Lauro Moscardini; Naoki Yoshida
2004-03-04

433

Characterizing switching problems in low earth orbit satellite constellations with satellite failures

  Texas A&M University - TxSpace

Summary: ACKs. D. Karn's Algorithm E. Slow Start. F. Big Window G. New Reno . FL SACK I. FACK J. Compression K. SCPS-TP L. Summary . APPENDIX B SATELLITE GEOMETRY Page 100 100 101 102 102 103 103 103 104 105 106 A. Summary of Orbital... window, ACK spacing, delayed DUP ACKs, selective ACKs, header and payload compression [3]. These solutions are described generically in Appendix A; here we will cover them in the context of GEO communications. Slow start defines connection startup...

Wadsworth, Brandon Scott
1999-01-01

434

1Hinode Satellite Power The Hinode satellite weighs approximately 700 kg (dry) and carries 170 kg of gas for

  Environmental Sciences and Ecology Websites

Summary: for up to two years. The satellite has two solar panels (blue) that produce all of the spacecraft's power by the solar panels when facing the sun? Can the satellite supply enough power to operate the experiments which.03 watts of power for each square centimeter of area, what is the total power produced by the solar panels


435

Fusion of satellite images of different spatial resolutions. 1 FUSION OF SATELLITE IMAGES OF DIFFERENT SPATIAL RESOLUTIONS

  Computer Technologies and Information Sciences Websites

Summary: assessment of the spectral quality of these products. Five sets of criteria are defined. They measureFusion of satellite images of different spatial resolutions. 1 FUSION OF SATELLITE IMAGES the performance of a method to synthesize the radiometry in a single spectral band as well as the multispectral

Boyer, Edmond

436

1Satellite Surface Areas The NASA Imager for Magnetosphere-to-Aurora Global Exploration (IMAGE) satellite was

  Geosciences Websites

Summary: are powered by solar cells on the satellite's outer surface. In this problem you will calculate the surface. Solar cells produce 0.0017 watts of electrical power per square centimeter from sunlight falling on their surfaces. What is the maximum power that can be produced by the satellite if only half of the solar cells


437

Satellite Image Automatic MapperTM -SIAMTM -Patent pending - Andrea Baraldi University of Maryland Satellite Image Automatic MapperTM

  Geosciences Websites

Summary: Satellite Image Automatic MapperTM - SIAMTM - Patent pending - © Andrea Baraldi University MapperTM - SIAMTM - Patent pending - © Andrea Baraldi University of Maryland - Email: andrea.baraldi@hermes.geog.umd.edu #12;Satellite Image Automatic MapperTM - SIAMTM - Patent pending - © Andrea Baraldi University

Kuligowski, Bob

438

10. The LAGEOS satellites are heavy brass and alumi-num satellites, of about 406 kg, completely passive

  Biology and Medicine Websites

Summary: 10. The LAGEOS satellites are heavy brass and alumi- num satellites, of about 406 kg, completely passive and covered with retroreflectors, orbiting about 6000 km above Earth's surface. LAGEOS, launched- ture but are in different orbits. The semimajor axis of LAGEOS is aI 12,270 km, the period PI 3

Bonhoeffer, Sebastian

439

NOAA Satellite and Information Service The National Environmental Satellite, Data, and Information Service (NESDIS) is dedicated to providing

  Environmental Sciences and Ecology Websites

Summary: Service NESDIS Line Offices National Climatic Data Center www.ncdc.noaa.gov/ National Geophysical Data Center www.ngdc.noaa.gov/ National Oceanographic Data Center www.nodc.noaa.gov/ Office of Systems Development www.osd.noaa.gov/ Office of Satellite Operations www.oso.noaa.gov/ Office of Satellite & Product


440

TriAnd and its Siblings: Satellites of Satellites in the Milky Way Halo

  CERN Preprints

Summary: We explore the Triangulum-Andromeda (TriAnd) overdensity in the SPLASH (Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo) and SEGUE (the Sloan Extension for Galactic Understanding and Exploration) spectroscopic surveys. Milky Way main sequence turn-off stars in the SPLASH survey reveal that the TriAnd overdensity and the recently discovered PAndAS stream (Martin et al. 2014) share a common distance (D ~ 20 kpc), position on the sky, and line-of-sight velocity (V_GSR ~ 50 km/s). Similarly, A-type, giant, and main sequence turn-off stars selected from the SEGUE survey in the vicinity of the Segue 2 dwarf show that TriAnd is prevalent in these fields, with a velocity and distance similar to the Segue 2 satellite. The coincidence of the PAndAS stream and Segue 2 satellite in positional and velocity space to TriAnd suggests that these substructures are all associated, and may be a fossil record of group-infall onto the Milky Way halo. In this scenario, the Segue 2 satellite and PAndAS stream are...

Deason, A J; Hamren, K M; Koposov, S E; Gilbert, K M; Beaton, R L; Dorman, C E; Guhathakurta, P; Majewski, S R; Cunningham, E C
2014-01-01

441

Segue 2: A Prototype of the Population of Satellites of Satellites

  CERN Preprints

Summary: We announce the discovery of a new Milky Way satellite Segue 2 found in the data of the Sloan Extension for Galactic Understanding and Exploration (SEGUE). We followed this up with deeper imaging and spectroscopy on the Multiple Mirror Telescope. From this, we derive a luminosity of M_v = -2.5, a half-light radius of 34 pc and a systemic velocity of -40$ km/s. Our MMT data also provides evidence for a stream around Segue 2 at a similar heliocentric velocity, and the SEGUE data show that it is also present in neighboring fields. We resolve the velocity dispersion of Segue 2 as 3.4 km/s and the possible stream as about 7 km/s. This object shows points of comparison with other recent discoveries, Segue 1, Boo II and Coma. We speculate that all four objects may be representatives of a population of satellites of satellites -- survivors of accretion events that destroyed their larger but less dense parents. They are likely to have formed at redshifts z > 10 and are good candidates for fossils of the reionization e...

Belokurov, V; Evans, N W; Gilmore, G; Irwin, M J; Mateo, M; Mayer, L; Olszewski, E; Bechtold, J; Pickering, T
2009-01-01

442

Toward a Satellite Algorithm Test Bed Report of a Workshop Organized by National Oceanic and Atmospheric

  Environmental Sciences and Ecology Websites

Summary: the scientific community access to all publicly available primary earth observing satellite data streams to obtain satellite data streams and independently create infrastructure to conduct research. In addition

Kuligowski, Bob

443

Satellite Application Facility for Numerical Weather Prediction Document NWPSAF-KN-UD-006

  Geosciences Websites

Summary: NWP SAF Satellite Application Facility for Numerical Weather Prediction Document NWPSAF-KN-UD-006 Satellite Application Facility on Numerical Weather Prediction (NWP SAF), under the Cooperation Agreement

Stoffelen, Ad

444

A Survey of Satellite Galaxies around NGC 4258

  CERN Preprints

Summary: We conduct a survey of satellite galaxies around the nearby spiral NGC 4258 by combining spectroscopic observations from the Apache Point Observatory 3.5-meter telescope with SDSS spectra. New spectroscopy is obtained for 15 galaxies. Of the 47 observed objects, we categorize 8 of them as probable satellites, 8 as possible satellites, and 17 as unlikely to be satellites. We do not speculate on the membership of the remaining 14 galaxies due to a lack of velocity and distance information. Radially integrating our best fit NFW profile for NGC 4258 yields a total mass of 1.8e12 Msun within 200 kpc. We find that the angular distribution of the satellites appears to be random, and not preferentially aligned with the disk of NGC 4258. In addition, many of the probable satellite galaxies have blue u-r colors and appear to be star-forming irregulars in SDSS images; this stands in contrast to the low number of blue satellites in the Milky Way and M31 systems at comparable distances.

Spencer, Meghin; Yoachim, Peter
2014-01-01

445

LARES succesfully launched in orbit: satellite and mission description

  General Relativity & Quantum Cosmology (arXiv)

Summary: On February 13th 2012, the LARES satellite of the Italian Space Agency (ASI) was launched into orbit with the qualification flight of the new VEGA launcher of the European Space Agency (ESA). The payload was released very accurately in the nominal orbit. The name LARES means LAser RElativity Satellite and summarises the objective of the mission and some characteristics of the satellite. It is, in fact, a mission designed to test Einstein's General Relativity Theory (specifically 'frame dragging' and Lense-Thirring effect). The satellite is passive and covered with optical retroreflectors that send back laser pulses to the emitting ground station. This allows accurate positioning of the satellite, which is important for measuring the very small deviations from Galilei-Newton's laws. In 2008, ASI selected the prime industrial contractor for the LARES system with a heavy involvement of the universities in all phases of the programme, from the design to the construction and testing of the satellite and separation system. The data exploitation phase started immediately after the launch under a new contract between ASI and those universities. Tracking of the satellite is provided by the International Laser Ranging Service. Due to its particular design, LARES is the orbiting object with the highest known mean density in the solar system. In this paper, it is shown that this peculiarity makes it the best proof particle ever manufactured. Design aspects, mission objectives and preliminary data analysis will be also presented.

Antonio Paolozzi; Ignazio Ciufolini
2013-05-29

446

The Distribution of Satellite Galaxies: The Great Pancake

  Astrophysics (arXiv)

Summary: The 11 known satellite galaxies within 250 kpc of the Milky Way lie close to a great circle on the sky. We use high resolution N-body simulations of galactic dark matter halos to test if this remarkable property can be understood within the context of the cold dark matter cosmology. We construct halo merger trees from the simulations and use a semianalytic model to follow the formation of satellite galaxies. We find that in all 6 of our simulations, the 11 brightest satellites are indeed distributed along thin, disk-like structures analogous to that traced by the Milky Way's satellites. This is in sharp contrast to the overall distributions of dark matter in the halo and of subhalos within it which, although triaxial, are not highly aspherical. We find that the spatial distribution of satellites is significantly different from that of the most massive subhalos but is similar to that of the subset of subhalos that had the most massive progenitors at earlier times. The elongated disk-like structure delineated by the satellites has its long axis aligned with the major axis of the dark matter halo. We interpret our results as reflecting the preferential infall of satellites along the spines of a few filaments of the cosmic web.

Noam I Libeskind; Carlos S Frenk; Shaun Cole; John C Helly; Adrian Jenkins; Julio F Navarro; Chris Power
2005-03-18

447

Satellite Infall and the Growth of Bulges of Spiral Galaxies

  Astrophysics (arXiv)

Summary: For bulges of spiral galaxies, the concentration, or Sersic index, increases with bulge luminosity and bulge-to-disk ratio B/D (Andredakis, Peletier, & Balcells 1995, MNRAS, 275, 874). Does this trend trace the growth of bulges via satellite accretion? And, is satellite infall consistent with this trend? Aguerri, Balcells, & Peletier (2001, A&A, 367, 428) investigated this question with N-body simulations of the accretion of dense, spheroidal satellites. Here, we expand on that work by running N-body simulations of the accretion of satellites that have realistic densities. Satellites are modelled as disk-bulge structures with their own dark-matter halo. A realistic density scaling with the primary galaxy is ensured by using the Tully-Fisher relation. Our merger models show that most satellites disrupt before reaching the center. However, a bulge-disk decomposition of the surface density profile after the accretion shows an increase of both the B/D and the Sersic index n of the bulge. The increase in the mass and concentration of the inner Sersic component is due to inward piling up of disk material due to transient bars during the satellite orbital decay. This research is described in Eliche-Moral, Balcells, Aguerri, & Gonzalez-Garcia, 2005 (in preparation).

M. C. Eliche-Moral; M. Balcells; J. A. L. Aguerri; A. C. Gonzalez-Garcia
2005-01-18

448

Anisotropic Distribution of SDSS Satellite Galaxies: Planar (not Polar) Alignment

  Astrophysics (arXiv)

Summary: The distribution of satellite galaxies relative to isolated host galaxies in the Sloan Digital Sky Survey (SDSS) is investigated. Host-satellite systems are selected using three different methods, yielding samples of ~3300, ~1600, and \\~950 satellites. In the plane of the sky, the distributions of all three samples show highly significant deviations from circular symmetry (> 99.99%, > 99.99%, and 99.79% confidence levels, respectively), and the degree of anisotropy is a strong function of the projected radius, r_p, at which the satellites are found. For r_p < 100 kpc, the SDSS satellites are aligned preferentially with the major axes of the hosts. This is in stark contrast to the Holmberg effect, in which satellites are aligned with the minor axes of host galaxies. The degree of anisotropy in the distribution of the SDSS satellites decreases with r_p and is consistent with an isotropic distribution at of order the 1-sigma level for 250 kpc < r_p < 500 kpc.

Tereasa G. Brainerd
2005-06-15

449

Satellite probing General Relativity and its extensions and Kolmogorov analysis

  General Relativity & Quantum Cosmology (arXiv)

Summary: We apply the Kolmogorov statistic to analyse the residual data of two LAGEOS satellites on General Relativistic Lense-Thirring effect, and show that it reveals a tiny difference in the properties of the satellites, possibly related to Yarkovsky-Rubincam effect. The recently launched LAser RElativity Satellite (LARES) can provide constraints to the extensions of General Relativity such as the Chern-Simons (CS) gravity with metric coupled to a scalar field through the Pontryagin density, so an explicit dependence on the frame dragging measurements vs the CS parameter is given.

V. G. Gurzadyan; I. Ciufolini; S. Sargsyan; G. Yegorian; S. Mirzoyan; A. Paolozzi
2013-06-24

450

Lasers for coherent optical satellite links with large dynamics

  CERN Preprints

Summary: We present the experimental realization of a laser system for ground to satellite optical Doppler ranging at the atmospheric turbulence limit. Such a system needs to display good frequency stability (a few parts in 10^{-14}) whilst allowing large and well controlled frequency sweeps of +/- 12 GHz at rates exceeding 100 MHz/s. Furthermore it needs to be sufficiently compact and robust for transportation to different astronomical observation sites where it is to be interfaced with satellite ranging telescopes. We demonstrate that our system fulfills those requirements and should therefore allow operation of ground to low Earth orbit satellite coherent optical links limited only by atmospheric turbulence.

Chiodo, Nicola; Acef, Ouali; Clairon, Andre; Wolf, Peter
2013-01-01

451

Satellite probing General Relativity and its extensions and Kolmogorov analysis

  CERN Preprints

Summary: We apply the Kolmogorov statistic to analyse the residual data of two LAGEOS satellites on General Relativistic Lense-Thirring effect, and show that it reveals a tiny difference in the properties of the satellites, possibly related to Yarkovsky-Rubincam effect. The recently launched LAser RElativity Satellite (LARES) can provide constraints to the extensions of General Relativity such as the Chern-Simons (CS) gravity with metric coupled to a scalar field through the Pontryagin density, so an explicit dependence on the frame dragging measurements vs the CS parameter is given.

Gurzadyan, V G; Sargsyan, S; Yegorian, G; Mirzoyan, S; Paolozzi, A
2013-01-01

452

Andean terraced hills (a use of satellite imagery)

  CERN Preprints

Summary: The aim of this paper is in stimulating the use of satellite imagery, in particular the free service of Google Maps, to investigate the distribution of the agricultural technique of terraced hills in Andean countries, near Titicaca Lake. In fact, satellite maps can give a clear view of the overall surface modified by human work, being then a precious help for on-site archaeological researches and for historical analysis. Satellite imagery is also able to give the distribution of burial and worship places. The paper discusses some examples near the Titicaca Lake.

Sparavigna, Amelia Carolina
2010-01-01

453

Submerged turbulence detection with optical satellites

  Astrophysics (arXiv)

Summary: During fall periods in 2002, 2003 and 2004 three major oceanographic expeditions were carried out in Mamala Bay, Hawaii. These were part of the RASP Remote Anthropogenic Sensing Program. Ikonos and Quickbird optical satellite images of sea surface glint revealed ~100 m spectral anomalies in km^2 averaging patches in regions leading from the Honolulu Sand Island Municipal Outfall diffuser to distances up to 20 km. To determine the mechanisms behind this phenomenon, the RASP expeditions monitored the waters adjacent to the outfall with an array of hydrographic, optical and turbulence microstructure sensors in anomaly and ambient background regions. Drogue tracks and mean turbulence parameters for 2x10^4 microstructure patches were analyzed to understand complex turbulence, fossil turbulence and zombie turbulence near-vertical internal wave transport processes. The dominant mechanism appears to be generic to stratified natural fluids including planet and star atmospheres and is termed beamed zombie turbulence maser action (BZTMA). Most of the bottom turbulent kinetic energy is converted to ~100 m fossil turbulence waves. These activate secondary (zombie) turbulence in outfall fossil turbulence patches that transmit heat, mass, chemical species, momentum and information vertically to the sea surface for detection in an efficient maser action. The transport is beamed in intermittent mixing chimneys.

Carl H. Gibson; R. Norris Keeler; Valery G. Bondur; Pak T. Leung; H. Prandke; D. Vithanage
2007-09-05

454

Astrometric Microlensing with the GAIA satellite

  Astrophysics (arXiv)

Summary: GAIA is the ``super-Hipparcos'' survey satellite selected as a Cornerstone 6 mission by the European Space Agency. GAIA can measure microlensing by the small excursions of the light centroid that occur during events. The all-sky source-averaged astrometric microlensing optical depth is about 10^{-5}. Some 25000 sources will have a significant variation of the centroid shift, together with a closest approach, during the lifetime of the mission. A covariance analysis is used to study the propagation of errors and the estimation of parameters from realistic sampling of the GAIA datastream of transits in the along-scan direction during microlensing events. Monte Carlo simulations are used to study the 2500 events for which the mass can be recovered with an error of less than 50 per cent. These high quality events are dominated by disk lenses within a few tens of parsecs and source stars within a few hundred parsecs. We show that the local mass function can be recovered from the high quality sample to good accuracy. GAIA is the first instrument with the capabilities of measuring the mass locally in very faint objects like black holes and very cool white and brown dwarfs. For only 5 per cent of all astrometric events will GAIA record even one photometric datapoint. There is a need for a dedicated telescope that densely samples the Galactic Centre and spiral arms, as this can improve the accuracy of parameter estimation by a factor of about 10.

V. A. Belokurov; N. W. Evans
2001-12-11

455

Generalized Morse Potential: Symmetry and Satellite Potentials

  HEP - Theory (arXiv)

Summary: We study in detail the bound state spectrum of the generalized Morse potential~(GMP), which was proposed by Deng and Fan as a potential function for diatomic molecules. By connecting the corresponding Schr\\"odinger equation with the Laplace equation on the hyperboloid and the Schr\\"odinger equation for the P\\"oschl-Teller potential, we explain the exact solvability of the problem by an $so(2,2)$ symmetry algebra, and obtain an explicit realization of the latter as $su(1,1) \\oplus su(1,1)$. We prove that some of the $so(2,2)$ generators connect among themselves wave functions belonging to different GMP's (called satellite potentials). The conserved quantity is some combination of the potential parameters instead of the level energy, as for potential algebras. Hence, $so(2,2)$ belongs to a new class of symmetry algebras. We also stress the usefulness of our algebraic results for simplifying the calculation of Frank-Condon factors for electromagnetic transitions between rovibrational levels based on different electronic states.

A. Del Sol Mesa; C. Quesne; Yu. F. Smirnov
1997-08-06

456

Tidal gravitational effects in a satellite

  General Relativity & Quantum Cosmology (arXiv)

Summary: Atomic wave interferometers are tied to a telescope pointing towards a faraway star in a nearly free falling satellite. Such a device is sensitive to the acceleration and the rotation relatively to the local inertial frame and to the tidal gravitational effects too. We calculate the rotation of the telescope due to the aberration and the deflection of the light in the gravitational field of a central mass (the Earth and Jupiter). Within the framework of a general parametrized description of the problem, we discuss the contributions which must be taken into account in order to observe the Lense-Thirring effect. Using a geometrical model, we consider some perturbations to the idealized device and we calculate the corresponding effect on the periodic components of the signal. Some improvements in the knowledge of the gravitational field are still necessary as well as an increase of the experimental capabilities; however our conclusions support a reasonable optimism for the future. Finally we put forward the necessity of a more complete, realistic and powerful model in order to obtain a definitive conclusion on the feasibility of the experiment as far as the observation of the Lense-Thirring effect is involved.

Philippe Tourrenc; Marie-Christine Angonin-Willaime; Xavier Ovido
2004-07-23

457

The population of natural Earth satellites

  CERN Preprints

Summary: We have for the first time calculated the population characteristics of the Earth's irregular natural satellites (NES) that are temporarily captured from the near-Earth-object (NEO) population. The steady-state NES size-frequency and residence-time distributions were determined under the dynamical influence of all the massive bodies in the solar system (but mainly the Sun, Earth, and Moon) for NEOs of negligible mass. To this end, we compute the NES capture probability from the NEO population as a function of the latter's heliocentric orbital elements and combine those results with the current best estimates for the NEO size-frequency and orbital distribution. At any given time there should be at least one NES of 1-meter diameter orbiting the Earth. The average temporarily-captured orbiter (TCO; an object that makes at least one revolution around the Earth in a co-rotating coordinate system) completes $(2.88\\pm0.82)\\rev$ around the Earth during a capture event that lasts $(286\\pm18)\\days$. We find a small pre...

Granvik, Mikael; Jedicke, Robert
2011-01-01

458

The Kinematics of the Ultra-Faint Milky Way Satellites: Solving the Missing Satellite Problem

  Astrophysics (arXiv)

Summary: We present Keck/DEIMOS spectroscopy of stars in 8 of the newly discovered ultra-faint dwarf galaxies around the Milky Way. We measure the velocity dispersions of Canes Venatici I and II, Ursa Major I and II, Coma Berenices, Hercules, Leo IV and Leo T from the velocities of 18 - 214 stars in each galaxy and find dispersions ranging from 3.3 to 7.6 km/s. The 6 galaxies with absolute magnitudes M_V < -4 are highly dark matter-dominated, with mass-to-light ratios approaching 1000. The measured velocity dispersions are inversely correlated with their luminosities, indicating that a minimum mass for luminous galactic systems may not yet have been reached. We also measure the metallicities of the observed stars and find that the 6 brightest of the ultra-faint dwarfs extend the luminosity-metallicity relationship followed by brighter dwarfs by 2 orders of magnitude in luminosity; several of these objects have mean metallicities as low as [Fe/H] = -2.3 and therefore represent some of the most metal-poor known stellar systems. We detect metallicity spreads of up to 0.5 dex in several objects, suggesting multiple star formation epochs. Having established the masses of the ultra-faint dwarfs, we re-examine the missing satellite problem. After correcting for the sky coverage of the SDSS, we find that the ultra-faint dwarfs substantially alleviate the discrepancy between the predicted and observed numbers of satellites around the Milky Way, but there are still a factor of ~4 too few dwarf galaxies over a significant range of masses. We show that if galaxy formation in low-mass dark matter halos is strongly suppressed after reionization, the simulated circular velocity function of CDM subhalos can be brought into approximate agreement with the observed circular velocity function of Milky Way satellite galaxies. [slightly abridged

Joshua D. Simon; Marla Geha
2007-07-26

459

DISCOVERING SIGNIFICANT EVOLUTION PATTERNS FROM SATELLITE IMAGE TIME SERIES

  Physics Websites

Summary: pixel (the radiometric levels of different wavelengths corresponding to infra-red, red, etc.), which. The next generation of satellites (e.g., V enµs, Sentinel-2) will actually be able to acquire image time

Paris-Sud XI, Université de

460

Satellite constellation design for mid-course ballistic missile intercept

  MIT - DSpace

Summary: This thesis will establish a conceptual approach to the design of constellations for satellite-based mid-course missile defense. The ballistic missile intercept problem leads to a new paradigm of coverage where interceptor ...

Sauter, Luke Michael, 1979-
2004-01-01

461

The Elemental Abundance Distributions of Milky Way Satellite Galaxies

  CERN Preprints

Summary: The chemical compositions of the stars in Milky Way (MW) satellite galaxies reveals the history of gas flows and star formation (SF) intensity. This talk presented a Keck/DEIMOS spectroscopic survey of the Fe, Mg, Si, Ca, and Ti abundances of nearly 3000 red giants in eight MW dwarf satellites. The metallicity and alpha-to-iron ratio distributions obey the following trends: (1) The more luminous galaxies are more metal-rich, indicating that they retained gas more efficiently than the less luminous galaxies. (2) The shapes of the metallicity distributions of the more luminous galaxies require gas infall during their SF lifetimes. (3) At [Fe/H] < -1.5, [alpha/Fe] falls monotonically with increasing [Fe/H] in all MW satellites. One interpretation of these trends is that the SF timescale in any MW satellite is long enough that Type Ia supernovae exploded for nearly the entire SF lifetime.

Kirby, Evan N
2010-01-01

462

Search for Dark Matter Satellites using the FERMI-LAT

  CERN Preprints

Summary: Numerical simulations based on the Lambda-CDM model of cosmology predict a large number of as yet unobserved Galactic dark matter satellites. We report the results of a Large Area Telescope (LAT) search for these satellites via the gamma-ray emission expected from the annihilation of weakly interacting massive particle (WIMP) dark matter. Some dark matter satellites are expected to have hard gamma-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We sought to identify LAT sources with these characteristics, focusing on gamma-ray spectra consistent with WIMP annihilation through the $b \\bar b$ channel. We found no viable dark matter satellite candidates using one year of data, and we present a framework for interpreting this result in the context of numerical simulations to constrain the velocity-averaged annihilation cross section for a conventional 100 GeV WIMP annihilating through the $b \\bar b$ channel.

Ackermann, M; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Bechtol, K; Bellazzini, R; Blandford, R D; Bloom, E D; Bonamente, E; Borgland, A W; Bottacini, E; Brandt, T J; Bregeon, J; Brigida, M; Bruel, P; Buehler, R; Burnett, T H; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Cecchi, C; Charles, E; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Conrad, J; Cutini, S; de Palma, F; Dermer, C D; Digel, S W; Silva, E do Couto e; Drell, P S; Drlica-Wagner, A; Essig, R; Falletti, L; Favuzzi, C; Fegan, S J; Focke, W B; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Germani, S; Giglietto, N; Giordano, F; Giroletti, M; Glanzman, T; Godfrey, G; Grenier, I A; Guiriec, S; Gustafsson, M; Hadasch, D; Hayashida, M; Hou, X; Hughes, R E; Johnson, R P; Johnson, A S; Kamae, T; Katagiri, H; Kataoka, J; Knodlseder, J; Kuss, M; Lande, J; Latronico, L; Lee, S -H; Lionetto, A M; Garde, M Llena; Longo, F; Loparco, F; Lovellette, M N; Lubrano, P; Mazziotta, M N; McEnery, J E; Michelson, P F; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Naumann-Godo, M; Norris, J P; Nuss, E; Ohsugi, T; Okumura, A; Orlando, E; Ormes, J F; Ozaki, M; Paneque, D; Pelassa, V; Pierbattista, M; Piron, F; Pivato, G; Porter, T A; Raino, S; Rando, R; Razzano, M; Reimer, A; Reimer, O; Ritz, S; Sadrozinski, H F -W; Sehgal, N; Sgro, C; Siskind, E J; Spinelli, P; Strigari, L; Suson, D J; Tajima, H; Takahashi, H; Tanaka, T; Thayer, J G; Thayer, J B; Tibaldo, L; Tinivella, M; Torres, D F; Troja, E; Uchiyama, Y; Usher, T L; Vandenbroucke, J; Vasileiou, V; Vianello, G; Vitale, V; Waite, A P; Wang, P; Winer, B L; Wood, K S; Yang, Z; Zalewski, S; Zimmer, S
2012-01-01

463

2011NOAA SATELLITE AND INFORMATION SERVICE Annual Repor t

  Geosciences Websites

Summary: Office Director 20 People and Awards 24 Annual Report Credits Layout & Artistic Design- Marc Pulliam and Information Service Assistant Administrator Mary Kicza at the Fairbanks Alaska Satellite Operations Facility


464

Achieving bounded delay on a time-varying satellite uplink

  MIT - DSpace

Summary: In this paper, we investigate the packet transmission delay in a time varying satellite uplink. Specifically, we are interested in bounding the packet transmission delay within the terminal router for uplink traffic in a ...

Wysocarski, Jeffrey S.

465

Why Baryons Matter: The Kinematics of Dwarf Spheroidal Satellites

  CERN Preprints

Summary: We use some of the highest resolution cosmological simulations ever produced of Milky Way-mass galaxies that include both baryons and dark matter to show that baryonic physics (energetic feedback from supernovae and subsequent tidal stripping) significantly reduces the dark matter mass in the central regions of luminous satellite galaxies. The reduced central masses of the simulated satellites reproduce the observed internal dynamics of Milky Way and M31 satellites as a function of luminosity. Including baryonic physics in Cold Dark Matter models naturally explains the observed low dark matter densities in the Milky Way's dwarf spheroidal population. Our simulations therefore resolve the tension between kinematics predicted in Cold Dark Mater theory and observations of satellites, without invoking alternative forms of dark matter.

Brooks, Alyson M
2012-01-01

466

How environment drives galaxy evolution: lessons learnt from satellite galaxies

  CERN Preprints

Summary: It is by now well established that galaxy evolution is driven by intrinsic and environmental processes, both contributing to shape the observed properties of galaxies. A number of early studies, both observational and theoretical, have shown that the star formation activity of galaxies depends on their environmental local density and also on galaxy hierarchy, i.e. centrals vs. satellites. In fact, contrary to their central (most massive) galaxy of a group/cluster, satellite galaxies are stripped of their gas and stars, and have their star formation quenched by their environment. Large galaxy surveys like SDSS now permit us to investigate in detail environment-driven transformation processes by comparing centrals and satellites. In this paper I summarize what we have so far learnt about environmental effects by analysing the observed properties of local central and satellite galaxies in SDSS, as a function of their stellar mass and the dark matter mass of their host group/cluster.

Pasquali, A
2015-01-01

467

istruzioni di montaggio Montiamo insieme il satellite Agile!

  Physics Websites

Summary: usare la colla nelle quattro asole intorno al cubo appena incollato arrotola gli elementi in foto ed rettangolari del pannello solare. unisci il pannello al satellite col- legando gli elementi in foto puoi


468

BUFFER MANAGEMENT SCHEMES FOR ENHANCED TCP PERFORMANCE OVER SATELLITE LINKS

  Engineering Websites

Summary: satellite networks. Our queue management schemes, Smallest Window First (SWF) and Smallest Sequence Number reduce the latency associated with transmitting short files (e.g., e-mails). SWF doubles the goodput

Modiano, Eytan

469

Characterization of Signal Deformations for GPS and WAAS Satellites

  Engineering Websites

Summary: was collected using SRI's 46 meter dish antenna, and involved 6 people in planning and operations. Multiple C satellite signals. INTRODUCTION The impact of signal deformation was first noticed in 1993[1]. Users

Stanford University

470

Aerospace Power & Electronics Simulation Workshop 2004 Satellite Attitude Control

  Computer Technologies and Information Sciences Websites

Summary: Aerospace Power & Electronics Simulation Workshop 2004 · Satellite Attitude Control System Design Using Reaction Wheels Bhanu Gouda Brian Fast Dan Simon #12;2Aerospace Power & Electronics Simulation;3Aerospace Power & Electronics Simulation Workshop 2004 ADCS ·ADCS: Attitude Determination and Control

Simon, Dan

471

SatMagazine Worldwide Satellite Magazine May 2009

  Geosciences Websites

Summary: .S. Satellite Industry? Something Brewing All Year `Round CEOS Technology for the Future Remote Sensing of these tropical cyclones, and NASA scientists conduct There's Always Something Brewing All Year `Round Map


472

From the Atlanta Workshop -Use Satellite Data for Model Evaluation

  Geosciences Websites

Summary: Atmosphere Workshop it was concluded that the low hanging fruit was more use of satellite data for model Assimilation ­ dries surface Control - Model too cool due to moisture Plan to revisit August 2006 Texas

Jacob, Daniel J.

473

The Fundamental Line of the Local Group Satellites

  Astrophysics (arXiv)

Summary: We present a new correlation between the mass-to-light (M/L) ratio and the mean metallicity for the satellites of the Local Group. This relation together with their central surface brightness define a Fundamental Line where metal poor and low surface brightness dwarfs are dark matter dominated while metal rich high surface brightness systems will have a low M/L ratio. This Fundamental Line is independent of distance to the central galaxy (M31 and the Milky Way) and morphological type among other global parameters as their star formation history. The new M/L-metallicity relation indicates that dwarf spheroidal galaxies are dark matter confined. It can be interpreted if satellites experienced a continuous loss of metals with a final episode of gas ejection at the end of the star formation epoch. Only Globular Clusters are found to lie outside the Fundamental Line of dwarf satellites. Unlike satellite galaxies they are not dark matter confined.

Francisco Prada; Andreas Burkert
2001-08-17

474

Micro-electromagnetic formation flight of satellite systems

  MIT - DSpace

Summary: Electromagnetic formation flight (EMFF) investigates the concept of using electromagnets to provide the forces to maintain a satellite's relative position in a formation. Thus far, high temperature superconducting (HTS) ...

Sakaguchi, Aya, S.M. Massachusetts Institute of Technology
2007-01-01

475

On the use of Satellite Television in High Energy Physics

  HEP - Experiment (arXiv)

Summary: This paper assesses the feasibility of exploiting commercial satellite television technologies to broadcast video signals and data from major High Energy Physics facilities to collaborating institutes throughout the world.

Lucas Taylor; David O. Williams
1998-10-24

476

Risk management of student-run small satellite programs

  MIT - DSpace

Summary: This paper proposes an approach for failure mode identification in university-affiliated, small satellite programs. These small programs have a unique set of risks due to many factors, including a typically inexperienced ...

Deems, Elizabeth (Elizabeth Carolina)
2007-01-01

477

The Generalized Information Network Analysis Methodology for Distributed Satellite Systems

  Engineering Websites

Summary: , performance and cost. The quantitative analysis methodology speci es measurable, unambiguous metrics. Validation of the methodology is provided by a comprehensive quantitative analysis of the NAVSTAR GlobalThe Generalized Information Network Analysis Methodology for Distributed Satellite Systems


478

A small satellite preliminary thermal control and heat shield analysis

  MIT - DSpace

Summary: As part of a student owned small satellite project, a preliminary thermal control and heat shield analysis was developed to verify acceptable performance requirements for the system. For the thermal control section, the ...

Melani Barreiro, Diego A
2008-01-01

479

Formation of dSph Satellites without Dark Matter

  CERN Preprints

Summary: Recently it was shown that low-mass galaxies containing no dark matter can naturally evolve to dSph-like satellites in a tidal field. Such dSph-like satellites fake total domination by dark matter. If this is correct then it must be possible to assemble appropriate precursors of dSph satellites. The genesis of dwarf galaxies in tidal tails appears to be a likely possibility. This is documented by theoretical work and observational surveys. However, it is not yet clear if the Milky Way could have sustained one or two mergers or fly-bys that were mild enough not to have destroyed the Galactic disc. The tidal arms could have been pulled from the incoming galaxy. Also, this scenario has to account for the correlation between brightness and metal abundance displayed by the Galactic dSph satellites, and lead to at least some debris on bound eccentric orbits.

Kroupa, P
1998-01-01

480

Studies on Replication of Cucumber Mosaic Virus Satellite RNA

  University of California eScholarship Repository

Summary: plant genome since there is a noticeable segmental sequenceplant genome. In addition, the satellite RNA of peanut stunt virus ( PSV) nucleotide sequenceplants. Although satRNA has no sequence homology with CMV genome,

Choi, Soon Ho
2011-01-01

481

A Comparative Study of Estimation Models for Satellite Relative Motion 

  Texas A&M University - TxSpace

Summary: sextant [2]. The development and launch of the Global Positioning System (GPS) allowed man to accurately predict where he is, anywhere on the Earth. Through the use of coordinated satellite information, man could know his exact location [3...

Desai, Uri
2013-01-31

482

Formation of dSph Satellites without Dark Matter

  Astrophysics (arXiv)

Summary: Recently it was shown that low-mass galaxies containing no dark matter can naturally evolve to dSph-like satellites in a tidal field. Such dSph-like satellites fake total domination by dark matter. If this is correct then it must be possible to assemble appropriate precursors of dSph satellites. The genesis of dwarf galaxies in tidal tails appears to be a likely possibility. This is documented by theoretical work and observational surveys. However, it is not yet clear if the Milky Way could have sustained one or two mergers or fly-bys that were mild enough not to have destroyed the Galactic disc. The tidal arms could have been pulled from the incoming galaxy. Also, this scenario has to account for the correlation between brightness and metal abundance displayed by the Galactic dSph satellites, and lead to at least some debris on bound eccentric orbits.

Pavel Kroupa
1998-01-07

483

The use of satellite-based technology in developing countries

  MIT - DSpace

Summary: Satellite technology in the areas of remote sensing, communication, and navigation can provide valuable information in a number of areas from business to disaster management to agriculture. There is great potential for ...

Wood, Danielle Renee
2007-01-01

484

Search for Dark Matter Satellites using the FERMI-LAT

  HEP - Experiment (arXiv)

Summary: Numerical simulations based on the Lambda-CDM model of cosmology predict a large number of as yet unobserved Galactic dark matter satellites. We report the results of a Large Area Telescope (LAT) search for these satellites via the gamma-ray emission expected from the annihilation of weakly interacting massive particle (WIMP) dark matter. Some dark matter satellites are expected to have hard gamma-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We sought to identify LAT sources with these characteristics, focusing on gamma-ray spectra consistent with WIMP annihilation through the $b \\bar b$ channel. We found no viable dark matter satellite candidates using one year of data, and we present a framework for interpreting this result in the context of numerical simulations to constrain the velocity-averaged annihilation cross section for a conventional 100 GeV WIMP annihilating through the $b \\bar b$ channel.

The Fermi LAT Collaboration; M. Ackermann; A. Albert; L. Baldini; J. Ballet; G. Barbiellini; D. Bastieri; K. Bechtol; R. Bellazzini; R. D. Blandford; E. D. Bloom; E. Bonamente; A. W. Borgland; E. Bottacini; T. J. Brandt; J. Bregeon; M. Brigida; P. Bruel; R. Buehler; T. H. Burnett; G. A. Caliandro; R. A. Cameron; P. A. Caraveo; J. M. Casandjian; C. Cecchi; E. Charles; J. Chiang; S. Ciprini; R. Claus; J. Cohen-Tanugi; J. Conrad; S. Cutini; F. de Palma; C. D. Dermer; S. W. Digel; E. do Couto e Silva; P. S. Drell; A. Drlica-Wagner; R. Essig; L. Falletti; C. Favuzzi; S. J. Fegan; W. B. Focke; Y. Fukazawa; S. Funk; P. Fusco; F. Gargano; S. Germani; N. Giglietto; F. Giordano; M. Giroletti; T. Glanzman; G. Godfrey; I. A. Grenier; S. Guiriec; M. Gustafsson; D. Hadasch; M. Hayashida; X. Hou; R. E. Hughes; R. P. Johnson; A. S. Johnson; T. Kamae; H. Katagiri; J. Kataoka; J. Knodlseder; M. Kuss; J. Lande; L. Latronico; S. -H. Lee; A. M. Lionetto; M. Llena Garde; F. Longo; F. Loparco; M. N. Lovellette; P. Lubrano; M. N. Mazziotta; J. E. McEnery; P. F. Michelson; W. Mitthumsiri; T. Mizuno; A. A. Moiseev; C. Monte; M. E. Monzani; A. Morselli; I. V. Moskalenko; S. Murgia; M. Naumann-Godo; J. P. Norris; E. Nuss; T. Ohsugi; A. Okumura; E. Orlando; J. F. Ormes; M. Ozaki; D. Paneque; V. Pelassa; M. Pierbattista; F. Piron; G. Pivato; T. A. Porter; S. Raino; R. Rando; M. Razzano; A. Reimer; O. Reimer; S. Ritz; H. F. -W. Sadrozinski; N. Sehgal; C. Sgro; E. J. Siskind; P. Spinelli; L. Strigari; D. J. Suson; H. Tajima; H. Takahashi; T. Tanaka; J. G. Thayer; J. B. Thayer; L. Tibaldo; M. Tinivella; D. F. Torres; E. Troja; Y. Uchiyama; T. L. Usher; J. Vandenbroucke; V. Vasileiou; G. Vianello; V. Vitale; A. P. Waite; P. Wang; B. L. Winer; K. S. Wood; Z. Yang; S. Zalewski; S. Zimmer
2012-01-12

485

On the use of Satellite Television in High Energy Physics

  CERN Preprints

Summary: This paper assesses the feasibility of exploiting commercial satellite television technologies to broadcast video signals and data from major High Energy Physics facilities to collaborating institutes throughout the world.

Taylor, L; Taylor, Lucas; Williams, David O.
1998-01-01

486

Assesment and Prediction of Natural Hazards from Satellite Imagery

  University of California eScholarship Repository

Summary: subsidence of the tsunami in Banda Aceh, Sumatra. Run-upimagery of tsunami effects in Banda Aceh. Science 308, 1596.Tsunami damage assessment using high resolution satellite imagery: a case study of Aceh,

Gillespie, Thomas; Chu, Jasmine; Frankenberg, Elizabeth; Thomas, Duncan
2007-01-01

487

An integrated evolutionary model approach to small satellite engineering

  MIT - DSpace

Summary: A deficiency exists in the use of detailed integrated modeling in the design, fabrication, and operations of small satellites (<180kg). This need led to the design of the Integrated Evolutionary Model (IEM) approach to ...

Robinson, Joseph B. (Joseph Brian)
2010-01-01

488

Multi-stakeholder Interactive Simulation for Federated Satellite Systems

  MIT - DSpace

Summary: Federated satellite systems (FSS) are a new class of space-based systems which emphasize a distributed architecture. New information exchanging functions among FSS members enable data transportation, storage, and processing ...

Grogan, Paul Thomas

489

Upper-bounding bias errors in satellite navigation

  CERN Preprints

Summary: A satellite navigation system for a safety critical application is required to provide an integrity alert of any malfunction; the probability that a navigation positioning error exceeds a given alert limit without an integrity alert is required to be smaller than a given integrity risk. So far, a little number of applications provide integrity alerts, because signal propagation from a satellite to a receiver depends on diversified phenomena and makes probabilistic upper-bound of possible threats difficult. To widen application fields of satellite navigation, two methods to upper-bound wide classes of bias errors are shown in this paper. The worst bias error in a maximum likelihood estimate caused by an interference signal within a given small power is derived. A novel inequality condition with a clock bias error and magnification coefficients that upper-bounds a horizontal position error is presented. Robustness of the inequality condition is numerically shown based on actual configurations of satellites.

Iwamoto, Takashi
2014-01-01

490

RESEARCH Open Access Application of satellite precipitation data to

  Geosciences Websites

Summary: RESEARCH Open Access Application of satellite precipitation data to analyse and model arbovirus GEOGRAPHICS © 2011 Schuster et al; licensee BioMed Central Ltd. This is an Open Access article distributed

Ebert, Beth

491

Satellite Meeting of "Kochi School on Random Schrodinger Operators"

  Mathematics Websites

Summary: Satellite Meeting of "Kochi School on Random Schr¨odinger Operators" 2009, Nov. 29 ­ 30 Kuroshio communications between foreign and Japanese graduate students. Schedule: Nov. 29 (Su.), 16:00 ­ 18:00 : Talks

Nakamura, Shu

492

Dynamic resource allocation DAMA alternatives study for satellite communications systems

  MIT - DSpace

Summary: We consider the design of demand assigned multiple access (DAMA) algorithms that efficiently utilize limited RF uplink resources for packet switched military satellite communication networks. In previous work, we designed ...

Yao, Huan

493

Satellite Remote Sensing of Mid-level Clouds

  Texas A&M University - TxSpace

Summary: -scale cloud variations, providing information from \\top down" viewpoint about the verti- cal distribution of cloud-top locations. However, the satellite imagers and sounders can only see the uppermost cloud top in each vertical column, and the statistics... by Nasiri et al. (2008). Their simulations show that hyperspectral measurements would serve an important role in re ning estimates of cloud phase. A wealth of high-resolution IR emission measurements from several satellite instruments, includ- ing AIRS...

Jin, Hongchun 1980-
2012-11-07

494

Satellite-viewed cloud signatures associated with extratropical cyclogenesis 

  Texas A&M University - TxSpace

Summary: SATELLITE-VIEWED CLOUD SIGNATURES ASSOCIATED WITH EXTRATROPICAL CYCLOGENESIS A Thesis by ROBERT LUCIEN LAPIERRE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1973 Major Subject: Meteorology SATELLITE-VIENED CLOUD SIGNATURES ASSOCIATED WITH EXTRATROPICAL CYCLOGENESIS A Thesis by ROBERT LUCIEN LAPIERRE Appi"o ed as to st~le and content by: n llcgrceo~& (C ai rman of Conmi t te~ YemberI Hay...

Lapierre, Robert Lucien
1973-01-01

495

Dwarf-spheroidal satellites: are they of tidal origin?

  Astrophysics (arXiv)

Summary: The Milky Way and Andromeda must have formed through an initial epoch of sub-structure merging. As a result of fundamental physical conservation laws tidal-dwarf galaxies (TDGs) have likely been produced. Here we show that such TDGs appear, after a Hubble-time of dynamical evolution in the host dark-matter halo, as objects that resemble known dSph satellite galaxies. We discuss the possibility that some of the Milky Way's satellites may be of tidal origin.

M. Metz; P. Kroupa
2007-01-10

496

Pre-solution of the perturbed motion of artificial satellite

  CERN Preprints

Summary: The authors try to find a good solution of an artificial satellite motion under the influence of J2 gravity in terms of KS variables by using Picard Iterative Method. The result shows that there are many solutions for this problem depends on the initial guess solutions, so the choice of correct and convince initial guess is very difficult. Applications of the method applied on many satellites.

Hassan, Inalds A; Basha, Mohammad A F
2012-01-01

497

Determination of wind from Nimbus-6 satellite sounding data

  Texas A&M University - TxSpace

Summary: DETERMINATION OF WIND FROM NIMBUS-6 SATELLITE SOUNDING DATA A Thesis by WILLIAM EVERETT CARLE Submitted to the Graduate College of Texas A&M University in partial fulfil!. ment of the requirement for the deg. . ec of MASTER OF SCIENCE... December 1979 Major Subject: Meteorology DETEIQ&INATION OE WIND PROS1 NINEDS-6 SATELLITE SOUNDING DATA A Thesis WILLIA11 EVERETT CARLE Aporoved as to style and content by: (Chairman of Commi tee) Nember) (Head of Department) December 1979...

Carle, William Everett
1979-01-01

498

A mathematical simulation of earth satellite explosion debris orbital elements

  Texas A&M University - TxSpace

Summary: A MATHEMATICAL SIKJLATION OF EARTH SATELLITE EXPLOSION DEBRIS ORBITAI ELEMENTS A Thesis WAYNE EDWARD NABREY Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of NASTER OF SCIENCE... Nay 1970 Major Subject Nathematics A MATHEMATICAL SlmZATION OZ EARTH SATELLITE EXPLOSION DEBRIS ORBITAL ELEMENTS A Thesis WAI? EDWARD MABREY Approved as to style and content by: haxrman o ommi tee Head o epartment mber Member May 1...

Mabrey, Wayne Edward
1970-01-01

499

The international status of intelligence-collecting reconnaissance satellites

  Texas A&M University - TxSpace

Summary: THE INTERNATIONAL STATUS OF INTELLIGENCE- COLLECTING RECONNAISSANCE SATELLITES A Thesis by BRENT ALLEN GATES Submitted to the Graduate College of Texas ASH University in partial fulfillment of the requirement for the degree of i~STER OF ARTS... May 1972 Major Subject: Political Science THE INTERNATIONAL STATUS OF INTELLIGENCE- COLLECTING RECONNAISSANCE SATELLITES A Thesis by BRENT ALLEN GATES Approved as to style and content by: (Chairman of Commit e) 09JD ' J 'd (Head of Department...

Gates, Brent Allen
1972-01-01

500

The international status of intelligence-collecting reconnaissance satellites 

  Texas A&M University - TxSpace

Summary: or more boosters, with final assembly of the satellite in outer space. Even if maximum allowable size were a factor in the launching and orbiting of space systems, it would not present a serious limitation to the operating capability of these parti... of launching. The second type of system was a photographic reconnais- sance satellite designed to provide both general and detailed imagery of the territories being overflown. The Soviet Union has released little information about their systems. Until 1962...

Gates, Brent Allen
1972-01-01

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