Loss of a satellite could explain Saturn’s obliquity and young rings

@article{Wisdom2022LossOA,  title={Loss of a satellite could explain Saturn’s obliquity and young rings},  author={Jack Wisdom and Rola Dbouk and Burkhard Militzer and William B. Hubbard and Francis Nimmo and Brynna G. Downey and Richard G. French},  journal={Science},  year={2022},  volume={377},  pages={1285 - 1289},  url={https://api.semanticscholar.org/CorpusID:252310492}}
The origin of Saturn’s ~26.7° obliquity and ~100-million-year-old rings is unknown. The observed rapid outward migration of Saturn’s largest satellite, Titan, could have raised Saturn’s obliquity through a spin-orbit precession resonance with Neptune. We use Cassini data to refine estimates of Saturn’s moment of inertia, finding that it is just outside the range required for the resonance. We propose that Saturn previously had an additional satellite, which we name Chrysalis, that caused Saturn… 

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37 References

The large obliquity of Saturn explained by the fast migration of Titan

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The results show that Saturn's rings are substantially younger than the planet itself and constrain models of their origin, and five small moons located in and around the rings are presented, confirming that the flows are very deep and likely extend down to the levels where magneticipation occurs.

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