The Role of Three-Body Resonances on the Dynamical History of the Saturnian Satellite System

Saturn have a dynamically diverse satellite system, featuring at least three orbital resonances among three pairs of moons: Mimas-Tethys with a ratio of 4:2, Enceladus-Dione with a ratio of 2:1, and Titan-Hyperion with a ratio of 4:3 mean-motion resonances. Previous studies of Saturn’s moon orbital histories typically assumed dominance of two-body resonances. Through direct numerical integrations, we’ve discovered that three-body resonances among Saturn’s satellites were prevalent in the past, leading to relatively extended capture times (10 million years or more). These three-body resonances consistently manifest as eccentricity types and don’t seem to influence moon inclinations. Some three-body resonances align closely with two-body resonances, involving the orbital precession of the third body, while others occur in isolation, unrelated to two-body resonances. It’s imperative that future research into the system’s history fully considers three-body resonances, which have been previously overlooked. This presentation will predominantly explore the era of the 3:1 resonance between Dione and Mimas, investigating its notable impact on shaping the current observed configuration of Mimas specifically, and Saturnian moons in general.