Tilting Saturn. II. Numerical Model

  title={Tilting Saturn. II. Numerical Model},
  author={Douglas P. Hamilton and William Rankin. Ward},
  journal={The Astronomical Journal},
  pages={2510 - 2517}
We argue that the gas giants Jupiter and Saturn were both formed with their rotation axes nearly perpendicular to their orbital planes, and that the large current tilt of the ringed planet was acquired in a post-formation event. We identify the responsible mechanism as trapping into a secular spin-orbit resonance that couples the angular momentum of Saturn's rotation to that of Neptune's orbit. Strong support for this model comes from (1) a near-match between the precession frequencies of… 

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