Unformatted text preview: orbital resonance with Dione , completing two orbits of Saturn for every one orbit completed by Dione. This resonance helps maintain Enceladus's orbital eccentricity (0.0047) and provides a heating source for Enceladus's geologic activity.  Like most of the larger satellites of Saturn, Enceladus rotates synchronously with its orbital period, keeping one face pointed toward Saturn. Unlike the Earth's moon, Enceladus does not appear to librate about its spin axis (more than 1.5°). However, analysis of the shape of Enceladus suggests that at some point it was in a 1:4 forced secondary spin-orbit libration.  This libration, like the resonance with Dione, could have provided Enceladus with an additional heat source....
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- Fall '10
- Astronomy, Natural satellite, Enceladus, dione, Moons of Saturn