Little Boy exploded over Hiroshima at 8:15 a.m. local time on August 6, 1945.
The bomb was released by the B-29 Enola Gay during the first wartime use of an atomic weapon. It detonated at an altitude above the city, producing a blast, intense heat, and radiation across Hiroshima.
The time is recorded in Japan Standard Time and is commonly paired with the date August 6. Three days later, another atomic bomb exploded over Nagasaki at 11:02 a.m. local time. Keeping the two times separate helps distinguish the two missions.
President Harry Truman announced the Hiroshima bombing in a statement sixteen hours after the attack. He warned Japan that continued resistance would bring further destruction, while the Soviet Union entered the war against Japan on August 8.