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Title: The ALEXIS mission recovery

Abstract

The authors report the recovery of the ALEXIS small satellite mission. ALEXIS is a 113-kg satellite that carries an ultrasoft x-ray telescope array and a high-speed VHF receiver/digitizer (BLACKBEARD), supported by a miniature spacecraft bus. It was launched by a Pegasus booster on 1993 April 25, but a solar paddle was damaged during powered flight. Initial attempts to contact ALEXIS were unsuccessful. The satellite finally responded in June, and was soon brought under control. Because the magnetometer had failed, the rescue required the development of new attitude control-techniques. The telemetry system has performed nominally. They discuss the procedures used to recover the ALEXIS mission.

Authors:
; ; ; ; ; ; ; ; ;  [1]; ; ; ; ; ;  [2]
  1. Los Alamos National Lab., NM (United States)
  2. AeroAstro, Inc., Herndon, VA (United States)
Publication Date:
Research Org.:
Los Alamos National Lab., NM (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
142518
Report Number(s):
LA-UR-94-503; CONF-940259-1
ON: DE94007549; TRN: AHC29407%%50
DOE Contract Number:
W-7405-ENG-36
Resource Type:
Conference
Resource Relation:
Conference: 17. annual American Astronomical Society (AAS) guidance and control conference, Keystone, CO (United States), 2-6 Feb 1994; Other Information: PBD: 1994
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; SATELLITES; PHOTOVOLTAIC POWER SUPPLIES; ELECTRONIC GUIDANCE; NAVIGATION; ATTITUDE CONTROL

Citation Formats

Bloch, J., Armstrong, T., Dingler, B., Enemark, D., Holden, D., Little, C., Munson, C., Priedhorsky, B., Roussel-Dupre, D., Smith, B., Warner, R., Dill, B., Huffman, G., McLoughlin, F., Mills, R., and Miller, R.. The ALEXIS mission recovery. United States: N. p., 1994. Web.
Bloch, J., Armstrong, T., Dingler, B., Enemark, D., Holden, D., Little, C., Munson, C., Priedhorsky, B., Roussel-Dupre, D., Smith, B., Warner, R., Dill, B., Huffman, G., McLoughlin, F., Mills, R., & Miller, R.. The ALEXIS mission recovery. United States.
Bloch, J., Armstrong, T., Dingler, B., Enemark, D., Holden, D., Little, C., Munson, C., Priedhorsky, B., Roussel-Dupre, D., Smith, B., Warner, R., Dill, B., Huffman, G., McLoughlin, F., Mills, R., and Miller, R.. Tue . "The ALEXIS mission recovery". United States. doi:. https://www.osti.gov/servlets/purl/142518.
@article{osti_142518,
title = {The ALEXIS mission recovery},
author = {Bloch, J. and Armstrong, T. and Dingler, B. and Enemark, D. and Holden, D. and Little, C. and Munson, C. and Priedhorsky, B. and Roussel-Dupre, D. and Smith, B. and Warner, R. and Dill, B. and Huffman, G. and McLoughlin, F. and Mills, R. and Miller, R.},
abstractNote = {The authors report the recovery of the ALEXIS small satellite mission. ALEXIS is a 113-kg satellite that carries an ultrasoft x-ray telescope array and a high-speed VHF receiver/digitizer (BLACKBEARD), supported by a miniature spacecraft bus. It was launched by a Pegasus booster on 1993 April 25, but a solar paddle was damaged during powered flight. Initial attempts to contact ALEXIS were unsuccessful. The satellite finally responded in June, and was soon brought under control. Because the magnetometer had failed, the rescue required the development of new attitude control-techniques. The telemetry system has performed nominally. They discuss the procedures used to recover the ALEXIS mission.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 01 00:00:00 EST 1994},
month = {Tue Mar 01 00:00:00 EST 1994}
}

Conference:
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  • In 2013, the U.S. Department of Energy's (DOE) Hanford Site, located in Washington State, funded an update to the critical network infrastructure supporting the Hanford Federal Cloud (HFC). The project, called ET-50, was the final step in a plan that was initiated five years ago called "Hanford's IT Vision, 2015 and Beyond." The ET-50 project upgraded Hanford's core data center switches and routers along with a majority of the distribution layer switches. The upgrades allowed HFC the network intelligence to provide Hanford with a more reliable and resilient network architecture. The culmination of the five year plan improved network intelligencemore » and high performance computing as well as helped to provide 10 Gbps capable links between core backbone devices (10 times the previous bandwidth). These improvements allow Hanford the ability to further support bandwidth intense applications, such as video teleconferencing. The ET-50 switch upgrade, along with other upgrades implemented from the five year plan, have prepared Hanford's network for the next evolution of technology in voice, video, and data. Hand-in-hand with ET-50's major data center outage, Mission Support Alliance's (MSA) Information Management (IM) organization executed a disaster recovery (DR) exercise to perform a true integration test and capability study. The DR scope was planned within the constraints of ET-50's 14 hour datacenter outage window. This DR exercise tested Hanford's Continuity of Operations (COOP) capability and failover plans for safety and business critical Hanford Federal Cloud applications. The planned suite of services to be tested was identified prior to the outage and plans were prepared to test the services ability to failover from the primary Hanford data center to the backup data center. The services tested were: Core Network (backbone, firewall, load balancers); Voicemail; Voice over IP (VoIP); Emergency Notification; Virtual desktops; and, Select set of production applications and data. The primary objective of the exercise was to test COOP around the emergency operations at Hanford to provide information on capabilities and dependencies of the current system to insure improved focus of emergency, safety and security capacity in a disaster situation. The integration of the DR test into the ET-50 project allowed the testing of COOP at Hanford and allowed the lessons learned to be defined. These lessons learned have helped improve the understanding of Hanford's COOP capabilities and will be critical for future planning. With the completion of the Hanford Federal Cloud network upgrades and the disaster recovery exercise, the MSA has a clearer path forward for future technology implementations as well as network improvements to help shape the usability and reliability of the Hanford network in support of the cleanup mission.« less
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  • The Array of Low Energy X-ray Imaging Sensors (ALEXIS) experiment consists of six wide angle EUV/ultrasoft x-ray telescopes utilizing normal incidence multilayer mirrors, flown a miniature satellite to map out the sky in three narrow bandpasses around 66, 71, and 95 eV. The 66 and 71 eV bandpasses are centered on intense Fe emission lines which are characteristic of million degree plasmas such as the one thought to produce the soft x-ray background. The 95 eV bandpass has a higher throughput and is more sensitive to continuum sources. The mission will be launched into orbit on the Pegasus Air Launchedmore » Vehicle in mid-1991. We will present the details of the ALEXIS telescope optical design, initial characterizations of the first flight mirrors and detectors, and the current schemes for characterizing and calibrating the completed telescope assemblies. We will also discuss the details of a novel wavetrap'' feature incorporated into the multilayer mirror structure to greatly reduce the mirror's reflectivity at 304 {angstrom}, a major background contamination flux of He II emission from the geocorona. 2 refs., 13 figs.« less
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