Ridge formation and de-spinning of Iapetus via an impact-generated satellite

  title={Ridge formation and de-spinning of Iapetus via an impact-generated satellite},
  author={Harold F. Levison and Kevin John Walsh and Amy C. Barr and Luke Dones},
Abstract We present a scenario for building the equatorial ridge and de-spinning Iapetus through an impact-generated disk and satellite. This impact puts debris into orbit, forming a ring inside the Roche limit and a satellite outside. This satellite rapidly pushes the ring material down to the surface of Iapetus, and then itself tidally evolves outward, thereby helping to de-spin Iapetus. This scenario can de-spin Iapetus an order of magnitude faster than when tides due to Saturn act alone… Expand

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