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Title: Voyager 1 Near the heliopause

Abstract

Recent observations from the Voyager 1 spacecraft show that it is sampling the local interstellar medium (LISM). This is quite surprising because no realistic, steady-state model of the solar wind (SW) interaction with the LISM gives an inner heliosheath width as narrow as ~30 AU. This includes models that assume a strong redistribution of the ion energy to the tails in the pickup ion distribution function. We show that the heliopause (HP), which separates the SW from the LISM, is not a smooth tangential discontinuity, but rather a surface subject to Rayleigh-Taylor-type instabilities which can result in LISM material penetration deep inside the SW. We also show that the HP flanks are always subject to a Kelvin-Helmholtz instability. The instabilities are considerably suppressed near the HP nose by the heliospheric magnetic field in steady-state models, but reveal themselves in the presence of solar cycle effects. Here we argue that Voyager 1 may be in one such instability region and is therefore observing plasma densities much higher than those in the pristine SW. Lastly, these results may explain the early penetration of Voyager 1 into the LISM. They also show that there is a possibility that the spacecraft may start samplingmore » the SW again before it finally leaves the heliosphere.« less

Authors:
 [1];  [2]
  1. Univ. of Alabama in Huntsville, AL (United States). Center for Space Physics and Aeronomic Research (CSPAR)
  2. Univ. of Alabama in Huntsville, AL (United States). Dept. of Space Sciences
Publication Date:
Research Org.:
Univ. of Alabama, Huntsville, AL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
OSTI Identifier:
1326044
Grant/Contract Number:  
SC0008334; NNX10AE46G; NNX10AC17G; NNX12AB30G; OCI-1144120
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Astrophysical Journal Letters
Additional Journal Information:
Journal Volume: 783; Journal Issue: 1; Journal ID: ISSN 2041-8205
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; ISM: kinematics and dynamics; ISM: magnetic fields; solar wind; Sun: heliosphere

Citation Formats

Borovikov, S. N., and Pogorelov, N. V. Voyager 1 Near the heliopause. United States: N. p., 2014. Web. doi:10.1088/2041-8205/783/1/L16.
Borovikov, S. N., & Pogorelov, N. V. Voyager 1 Near the heliopause. United States. https://doi.org/10.1088/2041-8205/783/1/L16
Borovikov, S. N., and Pogorelov, N. V. Tue . "Voyager 1 Near the heliopause". United States. https://doi.org/10.1088/2041-8205/783/1/L16. https://www.osti.gov/servlets/purl/1326044.
@article{osti_1326044,
title = {Voyager 1 Near the heliopause},
author = {Borovikov, S. N. and Pogorelov, N. V.},
abstractNote = {Recent observations from the Voyager 1 spacecraft show that it is sampling the local interstellar medium (LISM). This is quite surprising because no realistic, steady-state model of the solar wind (SW) interaction with the LISM gives an inner heliosheath width as narrow as ~30 AU. This includes models that assume a strong redistribution of the ion energy to the tails in the pickup ion distribution function. We show that the heliopause (HP), which separates the SW from the LISM, is not a smooth tangential discontinuity, but rather a surface subject to Rayleigh-Taylor-type instabilities which can result in LISM material penetration deep inside the SW. We also show that the HP flanks are always subject to a Kelvin-Helmholtz instability. The instabilities are considerably suppressed near the HP nose by the heliospheric magnetic field in steady-state models, but reveal themselves in the presence of solar cycle effects. Here we argue that Voyager 1 may be in one such instability region and is therefore observing plasma densities much higher than those in the pristine SW. Lastly, these results may explain the early penetration of Voyager 1 into the LISM. They also show that there is a possibility that the spacecraft may start sampling the SW again before it finally leaves the heliosphere.},
doi = {10.1088/2041-8205/783/1/L16},
url = {https://www.osti.gov/biblio/1326044}, journal = {Astrophysical Journal Letters},
issn = {2041-8205},
number = 1,
volume = 783,
place = {United States},
year = {2014},
month = {2}
}

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Free Publicly Available Full Text
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Cited by: 30 works
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Works referenced in this record:

Model of the solar wind interaction with the local interstellar medium: Numerical solution of self-consistent problem
journal, January 1993


The structure of the hydrodynamic plasma flow near the heliopause stagnation point
journal, January 2010


Plasma near the Heliosheath: Observations and Modeling
journal, January 2011


Consequences of the Heliopause Instability Caused by Charge Exchange
journal, August 2008


EVIDENCE FOR A SHOCK IN INTERSTELLAR PLASMA: VOYAGER 1
journal, October 2013


Magnetic Field Observations as Voyager 1 Entered the Heliosheath Depletion Region
journal, June 2013


No meridional plasma flow in the heliosheath transition region
journal, September 2012


Stationary plasma-field equilibrium states in astropause boundary layers - I. General theory
journal, December 1983


Energetic Particle Anisotropies at the Heliospheric Boundary
journal, October 2013


In Situ Observations of Interstellar Plasma with Voyager 1
journal, September 2013


An Estimate of the Nearby Interstellar Magnetic Field Using Neutral Atoms
journal, August 2011


The Effects of a κ‐Distribution in the Heliosheath on the Global Heliosphere and ENA Flux at 1 AU
journal, July 2008


PICK-UP IONS IN THE OUTER HELIOSHEATH: A POSSIBLE MECHANISM FOR THE INTERSTELLAR BOUNDARY EXplorer RIBBON
journal, December 2009


Search for the Exit: Voyager 1 at Heliosphere's Border with the Galaxy
journal, June 2013


Zero outward flow velocity for plasma in a heliosheath transition layer
journal, June 2011


A Model of Acceleration of Anomalous Cosmic rays by Reconnection in the Heliosheath
journal, August 2009


Hydrodynamic instability of the heliopause driven by plasma-neutral charge-exchange interactions
journal, August 1996


The Heliosphere's Interstellar Interaction: No Bow Shock
journal, May 2012


Global Observations of the Interstellar Interaction from the Interstellar Boundary Explorer (IBEX)
journal, October 2009


On the Rotation of the Magnetic Field Across the Heliopause
journal, November 2013


The Effects of a Local Interstellar Magnetic Field on Voyager 1 and 2 Observations
journal, March 2006


Interaction of the solar wind with the local interstellar medium
journal, November 1995


RADIAL VELOCITY ALONG THE VOYAGER 1 TRAJECTORY: THE EFFECT OF SOLAR CYCLE
journal, April 2012


HELIOSPHERIC ASYMMETRIES AND 2-3 kHz RADIO EMISSION UNDER STRONG INTERSTELLAR MAGNETIC FIELD CONDITIONS
journal, March 2009


Probing Heliospheric Asymmetries with an MHD-Kinetic model
journal, February 2008


INTERSTELLAR BOUNDARY EXPLORER MEASUREMENTS AND MAGNETIC FIELD IN THE VICINITY OF THE HELIOPAUSE
journal, November 2011


The Effects of Local Interstellar Magnetic Field on Energetic Neutral atom sky maps
journal, August 2012


Stability of MHD shear flows: Application to space physics
journal, March 2010


IS VOYAGER 1 INSIDE AN INTERSTELLAR FLUX TRANSFER EVENT?
journal, November 2013


Voyager 1 Observes Low-Energy Galactic Cosmic Rays in a Region Depleted of Heliospheric Ions
journal, June 2013


The dynamical heliosphere
conference, January 1999


Interaction of the solar wind with the local interstellar medium: A multifluid approach
journal, October 1996


    Works referencing / citing this record:

    Three-Dimensional Kinetic-Mhd Model of the Global Heliosphere with the Heliopause-Surface Fitting
    journal, October 2015


    The IBEX Ribbon and the Thickness of the Inner Heliosheath
    journal, July 2018


    Compressible and Incompressible Magnetic Turbulence Observed in the Very Local Interstellar Medium by Voyager 1
    journal, December 2019


    Heliosheath Processes and the Structure of the Heliopause: Modeling Energetic Particles, Cosmic Rays, and Magnetic Fields
    journal, April 2017


    The Heliotail
    journal, October 2015


    Magnetic field and particle measurements made by Voyager 2 at and near the heliopause
    journal, November 2019


    LOCAL INTERSTELLAR MAGNETIC FIELD DETERMINED FROM THE INTERSTELLAR BOUNDARY EXPLORER RIBBON
    journal, February 2016


    WHY ARE THE MAGNETIC FIELD DIRECTIONS MEASURED BY VOYAGER 1 ON BOTH SIDES OF THE HELIOPAUSE SO SIMILAR?
    journal, June 2014


    On the nature of the magnetic Rayleigh–Taylor instability in astrophysical plasma: the case of uniform magnetic field strength
    journal, July 2016


    An Exact Analytical Solution for the Interstellar Magnetic Field in the Vicinity of the Heliosphere
    journal, June 2015


    Magnetic Turbulence Spectra and Intermittency in the Heliosheath and in the Local Interstellar Medium
    journal, February 2019


    Electron Thermal Conduction as a Possible Physical Mechanism to make the Inner Heliosheath Thinner
    journal, October 2014