Collision Chains among the Terrestrial Planets. III. Formation of the Moon

@article{Asphaug2021CollisionCA,
  title={Collision Chains among the Terrestrial Planets. III. Formation of the Moon},
  author={Erik Asphaug and Alexandre Emsenhuber and Saverio Cambioni and Travis S. J. Gabriel and Stephen R. Schwartz},
  journal={The Planetary Science Journal},
  year={2021},
  volume={2}
}
In the canonical model of Moon formation, a Mars-sized protoplanet “Theia” collides with proto-Earth at close to their mutual escape velocity v esc and a common impact angle ∼45°. The “graze-and-merge” collision strands a fraction of Theia’s mantle into orbit, while Earth accretes most of Theia and its momentum. Simulations show that this produces a hot, high angular momentum, silicate-dominated protolunar system, in substantial agreement with lunar geology, geochemistry, and dynamics. However… 
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