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arXiv · 1206.4942

A modified "Type I migration" model for propeller moons in Saturn's rings

Matthew S. Tiscareno
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Abstract

We propose a mechanism for the observed non-keplerian motion (Tiscareno et al. 2010, ApJL) of "propeller" moons embedded in Saturn's rings. Our mechanism, in which radial variations in surface density -- external to, and unaffected by, the embedded moon -- result in an equilibrium semimajor axis for the moon due to "Type I" angular momentum exchange (Crida et al. 2010, AJ), provides a good fit to the observations. Future observations should distinguish between our model and others recently proposed.

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Matthew S. Tiscareno. 2012-06-21. A modified "Type I migration" model for propeller moons in Saturn's rings. https://doi.org/10.1016/j.pss.2012.07.012

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