There is a theory that the moon was formed when a planetoid struck the Earth. Both the Earth and the planetoid disintegrated, and then reformed into two bodies: the current Earth and the Moon.
The Moon is too large of a body for the Earth to have captured via gravity, which gave rise to the collision theory.
God formed the Earth.... the Moon and the Stars.
Same thing.
BTW, Mars had a close encounter, even bumping knuckles with a planetoid. There was a tremendous electrical exchange (think arc-welder) between the two planets before they bumped, carving the valleys we thought were carved by water, and creating giant lumps with arc marks all around them. When the two actually touched, the Valles Marineris was created.
Our ancestors described the 'war of the Gods' (Mars and something else bumping together) in mythology. That would have been quite a show.
That actually makes sense and I think I recall seeing (maybe on NOVA?) a computer simulation of how such a collision would have played out. Basically, the Earth and Moon are a binary system in a gravitational dance. The other planets with moons are hundreds and thousands of times larger and more massive than their satellites.