Zero outward flow velocity for plasma in a heliosheath transition layer

@article{Krimigis2011ZeroOF,
  title={Zero outward flow velocity for plasma in a heliosheath transition layer},
  author={Stamatios M. Krimigis and Edmond C. Roelof and R. Decker and Matthew E. Hill},
  journal={Nature},
  year={2011},
  volume={474},
  pages={359-361}
}
Voyager 1 has been in the reservoir of energetic ions and electrons that constitutes the heliosheath since it crossed the solar wind termination shock on 16 December 2004 at a distance from the Sun of 94 astronomical units (1 au = 1.5 × 108 km). It is now ∼22 au past the termination shock crossing. The bulk velocity of the plasma in the radial–transverse plane has been determined using measurements of the anisotropy of the convected energetic ion distribution. Here we report that the radial… 

No meridional plasma flow in the heliosheath transition region

TLDR
It is reported that, contrary to expectations, Voyager 1 observed a gradual slowing-down of radial plasma flow in the heliosheath to near-zero velocity, which yielded a meridional flow velocity of +3 ± 11 km s−1, that is, one consistent with zero within statistical uncertainties.

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