Origin of the Moon in a giant impact near the end of the Earth's formation

  title={Origin of the Moon in a giant impact near the end of the Earth's formation},
  author={Robin M. Canup and Erik Asphaug},
The Moon is generally believed to have formed from debris ejected by a large off-centre collision with the early Earth. The impact orientation and size are constrained by the angular momentum contained in both the Earth's spin and the Moon's orbit, a quantity that has been nearly conserved over the past 4.5 billion years. Simulations of potential moon-forming impacts now achieve resolutions sufficient to study the production of bound debris. However, identifying impacts capable of yielding the… 
Forming a Moon with an Earth-like Composition via a Giant Impact
Computer simulations show that a giant impact on early Earth could lead to a Moon with a composition similar to Earth’s, and simulate impacts involving larger impactors than previously considered that can produce a disk with the same composition as the planet's mantle, consistent with Earth-Moon compositional similarities.
Accretion of the Earth
  • R. Canup
  • Geology, Physics
    Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2008
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