Penetration of external plasma into a rotation‐driven magnetosphere

Thomsen et al. (2016) provide a new statistical analysis of nearly eight years of Cassini Plasma Spectrometer data, revealing that hot electrons injected from Saturn's outer magnetosphere penetrate into the inner magnetosphere, but only to a distinct inner edge whose location is independent of external solar wind properties. This result is fully consistent with the hypothesis that centrifugally driven interchange motion is responsible for plasma transport between inner and outer magnetosphere.