1. Fission theory - Earth may have been spinning so fast that a part of our planet may have spun off into space, but kept tethered by Earth’s gravity.
2. Capture theory - the moon originated elsewhere in the Milky Way.
3. Co-accretion theory - The moon and the Earth formed together when orbiting a black whole.
4. Giant impact hypothesis - A planetary object impacted Earth, causing a portion of the plant to come off and become the moon.
