Analytical description of physical librations of Saturnian coorbital satellites Janus and Epimetheus

  title={Analytical description of physical librations of Saturnian coorbital satellites Janus and Epimetheus},
  author={Philippe Robutel and N. Rambaux and Julie C. Castillo‐Rogez},
Abstract Janus and Epimetheus are famously known for their distinctive horseshoe-shaped orbits resulting from a 1:1 orbital resonance. Every 4 years these two satellites swap their orbits by a few tens of kilometers as a result of their close encounter. Recently Tiscareno et al. (Tiscareno, M.S., Thomas, P.C., Burns, J.A. [2009]. Icarus 204, 254–261) have proposed a model of rotation based on images from the Cassini orbiter. These authors inferred the amplitude of rotational librational motion… Expand

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