Science and Exploration

Origin Of The Moon

By Keith Cowing
Press Release
March 3, 2021
Filed under ,
Origin Of The Moon
The Moon

The Earth-Moon system is unusual in several respects. The Moon is roughly 1/4 the radius of the Earth – a larger satellite-to-planet size ratio than all known satellites other than Pluto’s Charon.

The Moon has a tiny core, perhaps with only ~1% of its mass, in contrast to Earth whose core contains nearly 30% of its mass. The Earth-Moon system has a high total angular momentum, implying a rapidly spinning Earth when the Moon formed. In addition, the early Moon was hot and at least partially molten with a deep magma ocean. Identification of a model for lunar origin that can satisfactorily explain all of these features has been the focus of decades of research.

Robin M. Canup, Kevin Righter, Nicolas Dauphas, Kaveh Pahlevan, Matija Ćuk, Simon J. Lock, Sarah T. Stewart, Julien Salmon, Raluca Rufu, Miki Nakajima, Tomáš Magna

Comments: Book chapter in “New Views on the Moon II”
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Geophysics (physics.geo-ph); Space Physics (
Cite as: arXiv:2103.02045 [astro-ph.EP] (or arXiv:2103.02045v1 [astro-ph.EP] for this version)
Submission history
From: Raluca Rufu
[v1] Tue, 2 Mar 2021 21:50:46 UTC (1,320 KB)

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