Three days later, another B-29 dropped an atomic bomb on Nagasaki. The “Little Boy” bomb exploded with the force of 12.5 kilotons of TNT, nearly destroying the city. The world entered the atomic age in August 1945, when the B-29 Superfortress nicknamed Enola Gay flew some 1,500 miles from the island of Tinian and dropped an atomic bomb on Hiroshima, Japan.