Artwork of the young Earth-Moon system. The Earth had recently formed when it was struck by a
protoplanet – called Theia – roughly three times the size of Mars. Debris from the impact went
into orbit, while the cores of the two planets merged. Within weeks of the event, the debris formed
a Saturn-like ring around the Earth. Later collisions in this ring led to the formation of the Moon,
probably within just a few thousand years. Initially the Earth and Moon were much closer together
than they are now, and spinning more quickly.
Moon Formation - V3