Image: US Government
Detonated on November 1, 1952 at Enewetak, an atoll in the Pacific Ocean, the 82-tonne block of a device codenamed Mike yielded an estimated 10.4 megatons of explosive power – almost 500 times that of the bomb dropped on Nagasaki. Ivy Mike is generally considered the world’s first triumphant test of an H bomb. The blast obliterated the island of Elugelab, creating an underwater crater 6,240 ft (1.9 km) wide and 164 ft (50 m) deep where the landmass had been.