The heliosphere—blowing in the interstellar wind

Abstract

Measurements of the velocity of interstellar He o inside of the heliosphere have been conducted over the past forty years. These historical data suggest that the ecliptic longitude of the direction of the interstellar flow has increased at an average rate of ∼ 0.19 • per year over time. Possible astronomical explanations for these short-term variations in the interstellar gas entering the heliosphere are presented.