There is pretty strong evidence that about 4.5 billion years ago the moon was formed as a result of early earths collision with another celestial body about the size of Mars namely Theia. The moon is most likely not a captured object but as a result of the debris thrown up due to this impact. The moons rocks contain many of the same elements and isotopic properties as earth rocks. If it were captured this would not be the case.
ThankTheBaker t1_jbirolg wrote
Reply to comment by XXAIgeneratedacctxXX in How much influence does a natural satellite (like the Moon) have on the formation of continents ? by Aubin_kun
There is pretty strong evidence that about 4.5 billion years ago the moon was formed as a result of early earths collision with another celestial body about the size of Mars namely Theia. The moon is most likely not a captured object but as a result of the debris thrown up due to this impact. The moons rocks contain many of the same elements and isotopic properties as earth rocks. If it were captured this would not be the case.