Where was the moon formed?
Volatile substances have a low abundance in lunar surface rocks as compared to terrestrial rocks. If this depletion is explained in terms of a late accretion of volatile materials from a solar nebula with falling temperature, then the conclusion can be drawn that the moon accumulated not in earth orbit but as a separate planet, and that it was later captured by the earth.
Singer
S F
SF
Bandermann
L W
LW