Collisionless encounters and the origin of the lunar inclination

@article{Pahlevan2015CollisionlessEA,
  title={Collisionless encounters and the origin of the lunar inclination},
  author={Kaveh Pahlevan and Alessandro Morbidelli},
  journal={Nature},
  year={2015},
  volume={527},
  pages={492-494}
}
The Moon is generally thought to have formed from the debris ejected by the impact of a planet-sized object with the proto-Earth towards the end of planetary accretion. Models of the impact process predict that the lunar material was disaggregated into a circumplanetary disk and that lunar accretion subsequently placed the Moon in a near-equatorial orbit. Forward integration of the lunar orbit from this initial state predicts a modern inclination at least an order of magnitude smaller than the… 

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