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Name: theta sig
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Date: 1993 - 1999

Is there any evidence that suggests that the moon was once part of the Earth?

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 gas cloud.

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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