Die Quelle des E Rings - das Enceladus Rätsel

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The sensational observations of the Cassini-Spacecraft during its close flyby at the E ring moon Enceladus (July 14th, 2005) open up completely new vistas on the creation, dynamics and sustainment of this largest ring of Saturn. We want to derive a kinetic model of this largest circum-planetary dust configuration in our Solar system by considering proper sources, dynamics and sinks in this region. While the sinks of the E ring dust are more or less known, the knowledge about the sources and the dust dynamics underwent substantial changes through to the recent Cassini observations. Cryovolcanism at Enceladus surface has to be considered as the main dust creation-process in addition to micro-meteoroid bombardment and the resulting particle ejecta (the latter process is possibly also relevant for Tethys). Moreover, the geophysical activities seem to exclusively occur at Enceladus south pole where beyond ice splitter also neutral gas is spit in the E ring region. This gas can sensitively influence the plasma- and magnetospheric environment in the vicinity of Enceladus orbit, and thus, the charging processes of the E ring particles. The major goal of this project is to theoretically investigate whether the CDA-data of the E ring in the vicinity of its main sources carry information about the process of particle creation and ejection at Enceladus and Tethys. This implies the question: How does the cryovolcanism at Enceladus influence the subsequent dynamics and with it the configuration of the whole E ring?