Nagasaki Atomic Bomb Museum
The atomic bomb was developed by scientists working under the Manhattan Project. The project was granted funding on December 6, 1941, with American leaders aiming for a new invention that would serve as a wartime weapon. The decision to drop an atomic bomb on Japan had been made by 1943, and a shortlist of candidate target cities was in place in 1945. At the time, it was argued that an atomic bombing would bring about a more rapid end to the war. Hiroshima, the first target, was selected to show the power of America's new weapon. The second bombing, of Nagasaki, was intended to demonstrate that the USA had a large arsenal. At 11:02 A.M. local time on August 9, 1945, the atomic bomb, nicknamed Fat Man as its code name by Robert Serber in the United States (after Sydney Greenstreet's character in "The Maltese Falcon") was dropped on Nagasaki, forever changing the city's landscape. A mushroom cloud rose to an altitude of 45,000 feet above the city.
Atomic bombings of Hiroshima and Nagasaki
After leaving Tinian the aircraft made their way separately to Iwo Jima to rendezvous with Sweeney and Marquardt at 05:55 at , and set course for Japan. The aircraft arrived over the target in clear visibility at . Parsons, who was in command of the mission, armed the bomb in flight to minimize the risks during takeoff. He had witnessed four B-29s crash and burn at takeoff, and feared that a nuclear explosion would occur if a B-29 crashed with an armed Little Boy on board. His assistant, Second Lieutenant Morris R. Jeppson, removed the safety devices 30 minutes before reaching the target area.
During the night of August 5–6, Japanese early warning radar detected the approach of numerous American aircraft headed for the southern part of Japan. Radar detected 65 bombers headed for Saga, 102 bound for Maebashi, 261 en route to Nishinomiya, 111 headed for Ube and 66 bound for Imabari. An alert was given and radio broadcasting stopped in many cities, among them Hiroshima. The all-clear was sounded in Hiroshima at 00:05. About an hour before the bombing, the air raid alert was sounded again, as "Straight Flush" flew over the city. It broadcast a short message which was picked up by "Enola Gay". It read: "Cloud cover less than 3/10th at all altitudes. Advice: bomb primary." The all-clear was sounded over Hiroshima again at 07:09.