Difficulties with the simple condensation hypothesis. Alternate explanation of Mercury's high density. The condensation model today. Siderophiles and lithophiles. Lunar rocks are dry.
Lunar rocks contain reduced metal.
Lunar and terrestrial rocks are both depleted in siderophiles. Oxygen and its isotopes. Isotopic abundances of oxygen in solar-system materials. Historical theories of the origin of the Moon. The modern Big Whack hypothesis.