The plutonium bomb was dropped on Nagasaki on August 9th 1945, three days after a uranium bomb had destroyed Hiroshima.

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Was it a plutonium bomb, like the ones it tested in 2006 and 2009, or one that used highly enriched uranium?

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The material that went into Fat Man, the plutonium bomb detonated over Nagasaki, was made at Hanford, which at its peak consisted of nine nuclear reactors and five plutonium reprocessing plants.

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