Moon once part of EARTH?
Name: theta sig
Date: 1993 - 1999
Is there any evidence that suggests that the moon was once part of
If so, when did it break away?
If not, where the heck did it come from, anyway?
There are three theories of the moon's origin:
1) the moon was part of the Earth and broke away early
in the Earth's history due to an impact with a large
meteor or asteroid.
2) the moon formed at the same time as the Earth and
in the same way -- gravitational collapse of a proto-stellar
3) the moon formed separately and was captured by the Earth's
gravitational field; we suspect this is what happened with
Mar's two moons.
Since the manned-moon landings starting in '69, moon rock
composition being very similar to Earth minerals suggests
that theory 1 or 2 is correct.
John (e-mail hawley)
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Update: June 2012