Hartmann, R Phillips & G Taylor (eds):
Origin of the Moon.
Lunar & Planetary Institute, Houston.
This thick compendium of papers presented at a meeting in Kona, Hawaii marked the emergence a new consensus on the origin of the Moon. At this meeting Hartmann, Don Davis and other scientists presented the theory that the Moon was formed by the collision of a Mars-sized planetesimal late in the formation of the Earth. The collision totally melted the Earth and threw off a ring of material from the Earth's crust and upper mantle, as well as some ejecta from the impactor. Some of this material accreted to make the Moon.