On the morning of March 1, 1954, the United States tested its largest thermonuclear bomb over Bikini Atoll in the Marshall Islands. Code-named “Castle Bravo”, the explosion was more than 1,000 times more powerful than the Hiroshima and Nagasaki bombs that had ended World War II a decade earlier. The Castle Bravo test surprised its engineers, yielding twice as much power as had been predicted, and a massive fireball that destroyed three neighboring islands and contaminated 18,000 square kilometers (7,000 square miles) of ocean with radioactive fallout to the east of Bikini. Directly in the path of the Castle Bravo fallout was Rongelap Atoll, where radioactive debris up to 2.5 centimeters (1 inch) deep was deposited on the atoll’s small islands and extensive coral reefs. Keep reading here!