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“Fat Man” Atomic Bomb

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The Challenges of Plutonium
The Pond Cabin
“Fat Man” Plutonium Bomb
One Microsecond
The Detonators
The V Site
The Concrete Bowl
The Quonset Hut
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Quick Fact:
Manhattan Project scientists designed the world's first atomic bombs: a uranium gun-type bomb, "Little Boy" and a plutonium implosion bomb, "Fat Man." The US dropped the Little Boy bomb on Hiroshima on August 6, 1945. Between 90,000 and 166,000 people are believed to have died from the bomb in the four-month period following the explosion. The Fat Man bomb, dropped on Nagasaki on August 9, 1945, killed about 80,000 Japanese by the end of 1945. Historians continue to debate the role of the atomic bombs in ending World War II.