An asymmetric solar wind termination shock

@article{Stone2008AnAS,
  title={An asymmetric solar wind termination shock},
  author={Edward C. Stone and Alan C. Cummings and Frank B. Mcdonald and Bryant C. Heikkila and N. K. Lal and W. R. Webber},
  journal={Nature},
  year={2008},
  volume={454},
  pages={71-74}
}
Voyager 2 crossed the solar wind termination shock at 83.7 au in the southern hemisphere, ∼10 au closer to the Sun than found by Voyager 1 in the north. This asymmetry could indicate an asymmetric pressure from an interstellar magnetic field, from transient-induced shock motion, or from the solar wind dynamic pressure. Here we report that 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… 

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TLDR
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Cool heliosheath plasma and deceleration of the upstream solar wind at the termination shock

TLDR
The termination shock is a weak, quasi-perpendicular shock that heats the thermal plasma very little and an unexpected finding is that the flow is still supersonic with respect to the thermal ions downstream of the termination shock.

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