Currently, the theory that best explains all the evidence about the formation of the Earth's moon is that the Earth was struck by a large object, possibly as
large as Mars. This theory says that enough debris was scattered from the Earth to form the Moon. Scientists can make movies of how this crash might have worked. The movies
show that such a crash produces a stream of completely vaporized
rock from the impact. It is thought that the Moon formed from this cooled material.
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