PLASMA IN THE HELIOSHEATH: 3.5 YEARS OF OBSERVATIONS

Richardson, J D; Wang, C

doi:10.1088/2041-8205/734/1/L21

Title: PLASMA IN THE HELIOSHEATH: 3.5 YEARS OF OBSERVATIONS

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Abstract

Voyager 2 (V2) has observed heliosheath (HSH) plasma since 2007 August. We describe how the plasma has evolved across the HSH. We show that the low solar wind dynamic pressure leads to an inward movement of the termination shock (TS) of about 10 AU to a minimum position of 73 AU in 2010. Near the TS large fluctuations are present in the HSH, but these fluctuations decrease as V2 moves further from the TS. The radial speed slowly decreases and the plasma flow slowly turns tailward. The temperature decreases across the HSH. The radial speed in 2011 remains above 100 km s{sup -1}, which implies that V2 is a substantial distance from the heliopause.

Authors:

Richardson, J D ^[1]; Wang, C ^[2]

Kavli Center for Astrophysics and Space Science, Massachusetts Institute of Technology, Cambridge 02139 (United States)
State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing (China)

Publication Date:: Fri Jun 10 00:00:00 EDT 2011

OSTI Identifier:: 21562609

Resource Type:: Journal Article

Journal Name:: Astrophysical Journal Letters

Additional Journal Information:: Journal Volume: 734; Journal Issue: 1; Other Information: DOI: 10.1088/2041-8205/734/1/L21; Journal ID: ISSN 2041-8205

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; FLUCTUATIONS; HELIOSPHERE; PLASMA; SOLAR WIND; VELOCITY; ATMOSPHERES; SOLAR ACTIVITY; SOLAR ATMOSPHERE; STELLAR ACTIVITY; STELLAR ATMOSPHERES; STELLAR WINDS; VARIATIONS

Citation Formats


                    Richardson, J D, and Wang, C. PLASMA IN THE HELIOSHEATH: 3.5 YEARS OF OBSERVATIONS.  United States: N. p., 2011. 
        Web.  doi:10.1088/2041-8205/734/1/L21.

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                    Richardson, J D, & Wang, C. PLASMA IN THE HELIOSHEATH: 3.5 YEARS OF OBSERVATIONS.  United States.  https://doi.org/10.1088/2041-8205/734/1/L21

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                    Richardson, J D, and Wang, C. 2011.  
        "PLASMA IN THE HELIOSHEATH: 3.5 YEARS OF OBSERVATIONS".  United States.  https://doi.org/10.1088/2041-8205/734/1/L21.

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@article{osti_21562609,

  title        = {PLASMA IN THE HELIOSHEATH: 3.5 YEARS OF OBSERVATIONS},

  author       = {Richardson, J D and Wang, C},

  abstractNote = {Voyager 2 (V2) has observed heliosheath (HSH) plasma since 2007 August. We describe how the plasma has evolved across the HSH. We show that the low solar wind dynamic pressure leads to an inward movement of the termination shock (TS) of about 10 AU to a minimum position of 73 AU in 2010. Near the TS large fluctuations are present in the HSH, but these fluctuations decrease as V2 moves further from the TS. The radial speed slowly decreases and the plasma flow slowly turns tailward. The temperature decreases across the HSH. The radial speed in 2011 remains above 100 km s{sup -1}, which implies that V2 is a substantial distance from the heliopause.},

  doi          = {10.1088/2041-8205/734/1/L21},

  url          = {https://www.osti.gov/biblio/21562609},
  journal      = {Astrophysical Journal Letters},

  issn         = {2041-8205},

  number       = 1,

  volume       = 734,

  place        = {United States},

  year         = {Fri Jun 10 00:00:00 EDT 2011},

  month        = {Fri Jun 10 00:00:00 EDT 2011}

}

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