Nagasaki was targeted by the atomic bomb named Fat Man.
The United States dropped Fat Man on Nagasaki on August 9, 1945, three days after Little Boy was used against Hiroshima. Fat Man was a plutonium implosion-type weapon carried by the B-29 bomber Bockscar, commanded by Major Charles Sweeney.
Nagasaki was not the mission's original target. The aircraft first approached Kokura, but cloud cover and smoke prevented a visual bombing run. The crew then flew to Nagasaki and released the bomb after finding a temporary opening in the clouds.
The bombing caused enormous loss of life and destruction, although Nagasaki's hilly terrain affected the spread of the blast. The attack occurred on the same day that Soviet forces began their offensive against Japanese positions in Manchuria.