At 11:02 a.m. on August 9, 1945 a plutonium implosion bomb, Fat Man, was dropped on Nagasaki. The yield was 22 kilotons. The damage was less extensive, due partly to the geography of the Nagasaki area and partly to the fact that the bomb was dropped about 2 miles off target. Of the 286,000 people living in Nagasaki at the time of the blast, 74,000 were killed and another 75,000 sustained injuries.

See Fission Bomb, Implosion Weapon, Manhattan Project.