Interstellar Helium Flow in the Solar System
Data from several satellites on the flow of interstellar helium in the solar system is presented here. The figure shows a compilation of the observations along with weighted mean values from all available observations.
Upper panel: direction of the helium flow in ecliptic coordinates.
Lower panel: flow speed and temperature.
It is evident that the direct observation of the neutral atoms by the GAS instrument provides the flow characteristics with the least uncertainty.