How did the Moon form and why is it crucial to life?
It would seem simplest to presume that the Earth and its Moon were simply two concentrations of matter from the protoplanetary disc around the Sun that were near enough together to orbit each other. But the studies to date suggest a much more extraordinary scenario. Also extraordinary is the suggestion by Ward and Brownlee that the presence and nature of the Moon was essential for the development of advanced life on the Earth.
