Impact processess

A major conclusion resulting from U.S. and Soviet imaging and sampling missions to the Moon is that all the soils and many near-surface rocks are impact ejecta, and that even pristine rock surfaces, when examined under all resolvable scales, are covered with impact craters. New results reported, pertaining to cratering on the Moon and the other terrestrial planets, range from data on the dynamic strength of a rock to energy partitioning and crater-stability calculations. New ideas on the role of volatiles in crater formation and criteria for recognition of impact melts were presented. New constraints on the size and flux rate of impacting objects in the zones of the terrestrial planets over the last 3 X 10^9 years were given.