Cassini Dust Measurements at Enceladus and Implications for the Origin of the E Ring
Abstract
During Cassini's close flyby of Enceladus on 14 July 2005, the High Rate Detector of the Cosmic Dust Analyzer registered micron-sized dust particles enveloping this satellite. The dust impact rate peaked about 1 minute before the closest approach of the spacecraft to the moon. This asymmetric signature is consistent with a locally enhanced dust production in the south polar region of Enceladus. Other Cassini experiments revealed evidence for geophysical activities near Enceladus' south pole: a high surface temperature and a release of water gas. Production or release of dust particles related to these processes may provide the dominant source of Saturn's E ring.
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Supplementary Material
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We thank T. V. Johnson for comments on the manuscript. The Potsdam group was supported by Deutsche Forschungsgemeinschaft grants Sp 384/16, Sp 384/17, and Sp 384/18; Deutsches Zentrum für Luft und Raumfahrt (DLR) grant 50OH0003; and the Studienstiftung des deutschen Volkes. The group at the Max Planck Institut für Kernphysik was supported by the Max Planck Society and by DLR under grant 500OH9802. The work in Chicago was supported by Jet Propulsion Laboratory contract 96 11 70, and M. Sremčević is funded by the Cassini UVIS project.
Information & Authors
Information
Published In
Science
Volume 311 • Issue 5766 • 10 March 2006
Pages: 1416 - 1418
History
Received: 14 October 2005
Accepted: 19 January 2006
Copyright
American Association for the Advancement of Science.
