Nagasaki was hit by the second atomic bomb before Japan accepted surrender terms in 1945.
The United States dropped the plutonium bomb known as Fat Man on Nagasaki on 9 August 1945. The first atomic bomb, Little Boy, had been dropped on Hiroshima three days earlier, on 6 August.
Nagasaki was not the original primary target for the second mission. Kokura was the primary target, but cloud and smoke obscured the aiming point, so the aircraft proceeded to Nagasaki. The bomb detonated over the Urakami Valley.
Japan’s decision to surrender also followed the Soviet Union’s declaration of war and invasion of Japanese-held Manchuria. Emperor Hirohito announced the decision in his 15 August broadcast, while the formal surrender was signed aboard USS Missouri on 2 September.