Fat Man

Fat Man was the codename for the type of nuclear bomb that was detonated over the Japanese city of Nagasaki by the United States on August 9, 1945, during World War II. It was the second of the only two nuclear weapons ever used in warfare, the first being Little Boy, which was dropped on Hiroshima three days earlier.

Development

The development of Fat Man was part of the Manhattan Project, a research and development undertaking during World War II that produced the first nuclear weapons. The bomb was an implosion-type nuclear weapon with a plutonium core. The design was more complex than the gun-type design used in Little Boy.

Design

Fat Man was an implosion-type weapon that used a core of plutonium-239. The bomb was 10.7 feet long, 5 feet in diameter, and weighed about 10,300 pounds. The design involved surrounding the plutonium core with high explosives that, when detonated, compressed the core to a supercritical state, initiating a nuclear chain reaction.

Deployment

The bomb was dropped by the B-29 Superfortress bomber Bockscar, piloted by Major Charles Sweeney. The intended target was the city of Kokura, but due to poor visibility, the mission was redirected to Nagasaki. The bomb exploded at an altitude of about 1,650 feet, with a yield of approximately 21 kilotons of TNT.

Impact

The explosion resulted in the immediate deaths of an estimated 40,000 to 75,000 people, with total casualties reaching up to 80,000 by the end of 1945 due to injuries and radiation sickness. The bombing of Nagasaki, along with the earlier bombing of Hiroshima, played a significant role in Japan's decision to surrender, leading to the end of World War II.

Legacy

The use of Fat Man and Little Boy remains a subject of intense debate and analysis. The bombings marked the only use of nuclear weapons in armed conflict and have had a lasting impact on international relations, military strategy, and the global movement for nuclear disarmament.

See also

• Little Boy
• Manhattan Project
• Nuclear weapon
• World War II
• Hiroshima and Nagasaki