Some Observations on High-Speed Impact*

This paper summarizes many of the experimental data that exist on phenomena associated with the impact of high-velocity particles; specifically, it discusses the impact of 20,000 ft./sec. particles produced by shaped charges, and the mechanics and energetics of crater formation. The probable mass of the meteorite that formed the Barringer Meteorite Crater of Arizona is calculated and found to be about 12,500 ordinary tons. The principal conclusions drawn from the data are that (a) probably only a small fraction of the total mass of a meteorite is vaporized on impact; (b) a meteorite may or may not shatter on impact; (c) the volume of the crater fixes rather closely the striking energy of the meteorite; and (d) there is some likelihood that high-velocity meteorites do not imbed themselves in the craters that they form.