Resonant capture of Saturn's arcs.

Abstract

Obtained images from the Cassini spacecraft have unveiled several small satellites in the vicinity of Mimas' orbit: Aegaeon, Methone and Anthe. Methone and Anthe are situated within arcs of material, while Aegaeon orbits within an arc near the inner edge of Saturn's G ring. The presence of these arcs and moons is consistent with their confinement by corotation eccentric resonance (CER) with Mimas. Aegaeon is captured in an inner 7 : 6 mean motion resonance with Mimas, while Methone and Anthe are, respectively, captured in outer 14 : 15 and 10 : 11 resonances with Mimas. Here, we estimate the probabilities of capturing these small satellites into their respective CERs with Mimas as the orbit of the latter evolves through tidal effects. We will discuss the potential implications of this work, in particular the constraints it may provide on Mimas' orbital evolution.This article is part of the theme issue 'Major advances in planetary sciences thanks to stellar occultations'.