Operation Crossroads
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English: Operation Crossroads was an atmospheric nuclear weapon test series conducted by the United States in the summer of 1946. The series consisted of two detonations, each with a yield of 21 kilotons: ABLE detonated at an altitude of 520 feet (158 m) on 1 July 1946; BAKER detonated 90 feet (27 m) underwater on 25 July 1946.