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arXiv · 2103.02045

Origin of the Moon

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
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Abstract

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.

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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. 2021-03-02. Origin of the Moon. https://arxiv.org/abs/2103.02045

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