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National Museum of Nuclear Science & History

John Coster-Mullen is a nuclear archaeologist and author of Atom Bombs: The Top Secret, Inside Story of Little Boy and Fat Man. He worked as a corporate and advertising photographer for over 30 years and now drives trucks around the country. In his spare time, Coster-Mullen researches the creation of the atomic bomb.

Coster-Mullen became interested in the creation and history of the bombs as early as the seventh-grade, when the first photographs of Little Boy and Fat Man were released. He has spent over 25 years uncovering how these machines functioned by interviewing Manhattan Project scientists, mechanics, and engineers, requesting government documents, and doing his own calculations. In 2004, he completed a full-scale, exact replica of the Little Boy bomb, which is on display at the Historic Wendover Airfield Museum in Utah and is signed by dozens of the surviving veterans of the 509th Composite Air Group that dropped these bombs on Japan. In 2001, the members of the 509th voted to make him a Permanent Honorary Member of their group.

John Coster-Mullen has played a crucial role in establishing a public, permanent record of the creation of the bomb. In an article about him in The New Yorker, he is quoted saying, “The secret of the atomic bomb is how easy they are to make.”

Coster-Mullen continues to search for nuclear artifacts and speak publicly about his research. 

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