The Third Shot was the first of a series of American nuclear weapons intended for use against Japan in World War II, subsequent to the nuclear attacks on Hiroshima and Nagasaki. It was intended to be used on 19 August 1945, ten days after the bombing of Nagasaki.[1] It was never used, as the surrender of Japan on 15 August brought the war to a close first.[1][2]
The Third Shot was a plutonium-239-based implosion bomb of the "Fat Man" design, similar to the bomb that was dropped on Nagasaki.[2]