coaccretion hypothesis
Quick Summary
The coaccretion hypothesis suggests that the Moon and Earth formed simultaneously from a primordial accretion disk. This disk, composed of gas, plasma, dust, and particles, slowly collapsed inward around a central astronomical object. As material condensed and debris was pulled in, both Earth and the Moon grew. Earth's larger mass allowed it to develop a stronger gravitational pull, leading the Moon to orbit it. However, this theory has been challenged for failing to fully explain the current angular momentum of the Moon around Earth. Other theories for the Moon's formation include the fission of Earth, capture of a pre-formed Moon, and remnants from a collision with a planet called Theia.1
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