BAKER test, Bikini Atoll, July 25, 1946 (b/w photo)

Operation Crossroads was a series of nuclear weapons tests conducted by the United States at Bikini Atoll in the Marshall Islands in 1946. The purpose of the operation, which included two shots, ABLE and BAKER, was to investigate the effect of nuclear weapons on naval warships. They were the first tests to be publicly announced beforehand and observed by an invited audience, which included a large press corps. The second test, codenamed BAKER, occured on July 25, 1946 when an implosion-type bomb suspended 90 feet underwater exploded with a yield of 23 kilotons.