Heliospheric shocks and sheaths Available to Purchase

The Voyager spacecraft are both in the heliosheath, observing its properties in situ for the first time. This paper describes plasma observations in the heliosheath and compares its properties with those of planetary magnetosheaths and interplanetary coronal mass ejection (ICME) sheaths. Reflected ions are observed or inferred to be present in all three types of sheaths, although the percentage of reflected ions is highly variable. The heliosheath velocity variations are much smaller than those in magnetosheaths, probably due to the decreased role of large‐scale boundary motions. The density variation in these two sheaths are comparable, which we suggest is due to small scale shock motions (speed and normal changes) being comparable for these two types of shock. The radial plasma flux decreases across the heliosheath due to a combination of decreased solar output and the turning of flow down the heliotail.