Castle Bravo and Bikini Atoll

Castle Bravo was the code name given to the first U. S. test of a dry fuel thermonuclear hydrogen bomb device, detonated on March 1, 1954 at Bikini Atoll, Marshall Islands, as the first test of Operation Castle. Fallout from the detonation intended to be a secret test poisoned the islanders who had previously inhabited the atoll and returned there afterwards, as well as the crew of Daigo Fukuryū Maru ( Lucky Dragon No. 5 ), a Japanese fishing boat.