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The United States detonated its fifth nuclear device underwater at Bikini Atoll
Featured Event 1946 Event

July 25

Bikini Nuke: Atomic Bomb Detonated Underwater

The United States detonated its fifth nuclear device underwater at Bikini Atoll on July 25, 1946, as part of Operation Crossroads, designed to test the effects of atomic weapons on naval vessels. The underwater "Baker" shot created a massive column of radioactive water that contaminated the target fleet so severely that most ships could never be safely crewed again. Sailors sent to scrub the decks were exposed to radiation levels that weren't fully understood at the time. The 167 residents of Bikini Atoll had been relocated before the tests with promises they could return; they never did. The atoll remains too contaminated for permanent habitation, and "Bikini" entered fashion vocabulary when a French designer named his revealing swimsuit after the explosive test.

July 25, 1946

80 years ago

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