--onsored by Los Alamos National Laboratory, the Rebound experiment was conducted at 10 a.m. Pacific Daylight Time in the U1A complex, a horizontal tunnel mined about 960 feet beneath the ground surface. The purpose of Rebound was to obtain information on the response of plutonium to shock wave compression under different high pressure conditions (several million times atmospheric pressure).

--xplosive energy was directed at about two dozen pieces of plutonium with a total mass of less than 1.5 kilograms (3.3 pounds) with the largest being 70 grams (2.5 ounces