
This Day in History: Hydrogen bomb, Bravo, detonated on Bikini Atoll.
• Andrew PetcherCastle Bravo was the most powerful nuclear device ever detonated by the United States, with a yield of fifteen Megatons. That yield, far exceeding the expected yield of four to six megatons which, combined with other factors, led to the most significant accidental radiological contamination ever caused by the United States. In terms of TNT tonnage equivalence, Castle Bravo was about one thousand, two hundred times more powerful than each of the atomic bombs which were dropped on Hiroshima and Nagasaki during World War II.