Degree-one convection and the origin of Enceladus’ dichotomy
Recently, the Cassini spacecraft has detected ongoing geologic activity near the south pole of Saturn’smoon Enceladus. In contrast, the satellite’s north-polar region is heavily cratered and appears to have been geologically inactive for a long time. We propose that this hemispheric dichotomy is cau...
| Published in: | Icarus |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
Elsevier
2007
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| Subjects: | |
| Online Access: | https://elib.dlr.de/51676/ |
| Summary: | Recently, the Cassini spacecraft has detected ongoing geologic activity near the south pole of Saturn’smoon Enceladus. In contrast, the satellite’s north-polar region is heavily cratered and appears to have been geologically inactive for a long time. We propose that this hemispheric dichotomy is caused by interior dynamics with degree-one convection driving the south-polar activity. We investigate a number of core sizes and internal heating rates for which degree-one convection occurs. The numerical simulations imply that a core radius of less than 100±20 km and an energy input at a rate of 3.0 to 5.5 GW would be required for degree-one convection to prevail. This is within the range of the observed thermal power release near Enceladus’ south pole. Provided that Enceladus is not fully differentiated, degree-one convection is found to be a viable mechanism to explain Enceladus’ hemispheric dichotomy. |
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