Nagasaki was struck by the atomic bomb nicknamed “Fat Man” on August 9, 1945.
The weapon was carried by the B-29 bomber Bockscar and detonated at about 11:02 a.m. local time. Fat Man used plutonium and was more complex in design than Little Boy, the uranium bomb dropped on Hiroshima three days earlier.
Nagasaki was not the original aiming point that morning. The aircraft first approached Kokura, but cloud and smoke obscured the target, so the crew turned toward Nagasaki. The bomb exploded over the city’s Urakami Valley area.
The bombing came as Japan’s leaders were already confronting the consequences of Hiroshima and the Soviet Union’s declaration of war. Japan announced its acceptance of the Allied terms on August 15, although the formal surrender followed in September.