Crossing the Termination Shock into the Heliosheath: Magnetic Fields

  title={Crossing the Termination Shock into the Heliosheath: Magnetic Fields},
  author={L. Burlaga and N. Ness and M. Acuna and R. Lepping and J. Connerney and E. Stone and F. Mcdonald},
  pages={2027 - 2029}
Magnetic fields measured by Voyager 1 show that the spacecraft crossed or was crossed by the termination shock on about 16 December 2004 at 94.0 astronomical units. An estimate of the compression ratio of the magnetic field strength B (± standard error of the mean) across the shock is B2/B1 = 3.05 ± 0.04, but ratios in the range from 2 to 4 are admissible. The average B in the heliosheath from day 1 through day 110 of 2005 was 0.136 ± 0.035 nanoteslas, ∼4.2 times that predicted by Parker's… Expand
Tsallis Statistics of the Magnetic Field in the Heliosheath
The spacecraft Voyager 1 crossed the termination shock on 2004 December 16 at a distance of 94 AU from the Sun, and it has been moving through the heliosheath toward the interstellar medium sinceExpand
Multiscale structure of magnetic fields in the heliosheath
[1] Voyager 1 (V1) crossed the termination shock, leaving the solar wind and entering the heliosheath. This paper analyzes the magnetic field observed in the heliosheath from day of year 1 to 308,Expand
Magnetic Fields in the Heliosheath: Voyager 1 Observations
Magnetic fields in the heliosheath were observed by Voyager 1 (V1) from 2004 DOY 352 to 2005 125, when V1 moved from 94.04 to 95.24 AU at 341N. The strongest fields (0.31 nT, observed on 2005 DOYExpand
Voyager observations of magnetic fields and cosmic rays in the heliosheath
[1] The major features of the profile of >70 MeV/nuc cosmic ray intensity (CRI) observed by Voyager 1 (V1) in the heliosheath from 2005.8–2010.24 are described by the empirical “CR-B” relation as theExpand
This paper describes the principal features of 24 hr averages of the magnetic field strength variations B(t) and their relationships to the plasma and energetic particles observed prior to and afterExpand
Magnetic fields at the solar wind termination shock
Observations of the magnetic field structure and dynamics of the termination shock made by Voyager 2 on 31 August–1 September 2007 reveal a complex, rippled, quasi-perpendicular supercritical magnetohydrodynamic shock of moderate strength undergoing reformation on a scale of a few hours. Expand
Observations of the Magnetic Field and Plasma in the Heliosheath by Voyager 2 from 2007.7 to 2009.4
The density and temperature profiles of the plasma measured by Voyager 2 (V2) behind the termination shock changed abruptly near 2008.6 from relatively large average values and large fluctuationsExpand
An asymmetric solar wind termination shock
The intensity of 4–5 MeV protons accelerated by the shock near Voyager 2 was three times that observed concurrently by Voyager 1, indicating differences in the shock at the two locations. Expand
Sectors and Large-Scale Magnetic Field Strength Fluctuations in the Heliosheath Near 110 AU: Voyager 1,2009
This paper describes observations of daily averages of the magnetic field strength B and the magnetic polarity measured by Voyager 1 (V1) in the heliosheath during 2009 between 108.5 and 112.1 AU andExpand
Heliosphere Termination Shock as a Transformer of Magnetic Field from Lognormal to Normal Distribution
A mechanism is proposed to demonstrate that the strength of magnetic field can be transformed from a lognormal to a normal distribution as the solar wind passes through the heliosphere terminationExpand


Voyager 1 exited the solar wind at a distance of ∼85 au from the Sun
The outer limit of the Solar System is often considered to be at the distance from the Sun where the solar wind changes from supersonic to subsonic flow. Theory predicts that a termination shockExpand
Search for the heliosheath with Voyager 1 magnetic field measurements
The magnetic field measured by Voyager 1 (V1) near 85 AU from 2002.0 to 2003.17 has the expected properties for the heliospheric magnetic field at that distance and epoch of the solar cycle. These V1Expand
Enhancements of energetic particles near the heliospheric termination shock
A significant increase in the numbers of energetic ions and electrons that persisted for seven months beginning in mid-2002 is reported, arguing that the radial anisotropy of the cosmic rays is expected to be small in the foreshock region, as is observed. Expand
Voyager 1 Explores the Termination Shock Region and the Heliosheath Beyond
The intensity of anomalous cosmic ray (ACR) helium did not peak at the shock, indicating that the ACR source is not in the shock region local to Voyager 1, and the intensities of ∼10–megaelectron volt electrons, ACRs, and galactic cosmic rays have steadily increased since late 2004. Expand
Voyager 1 in the Foreshock, Termination Shock, and Heliosheath
Observations from Voyager 1 are interpreted as evidence that V1 was crossed by the TS on 2004/351 (during a tracking gap) at 94.0 astronomical units, evidently as the shock was moving radially inward in response to decreasing solar wind ram pressure, and that V 1 has remained in the heliosheath until at least mid-2005. Expand
News from the Edge of Interstellar Space
Auroral activity and magnetic storms that occasionally disrupt electric power grids are caused by the supersonic solar wind that sweeps past Earth as it blows radially away from the Sun. This Expand
Electron Plasma Oscillations Upstream of the Solar Wind Termination Shock
Electron plasma oscillations have been detected upstream of the solar wind termination shock by the plasma wave instrument on the Voyager 1 spacecraft, consistent with the spacecraft having crossed the termination shock into the heliosheath. Expand
Solar wind speed and coronal flux-tube expansion
The hypothesis that the solar wind speed at 1 AU and the rate of magnetic flux-tube expansion in the corona are inversely correlated is shown to be consistent with observations extending over theExpand
Motion of the termination shock in response to an 11 Year variation in the solar wind
A two-dimensional hydrodynamic numerical model has been used to study the motion of the termination shock in response to an 11 year variation in the solar wind ram pressure. We find that for a totalExpand
Solar cycle induced variations of the outer heliospheric structures
[1] The solar wind undergoes complicated but typical changes during the solar activity cycle which are especially strongly pronounced in the inner heliosphere. In the outer heliosphere, as the mainExpand