Nuclear Museum Logo
Nuclear Museum Logo

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 continued to search for nuclear artifacts and speak publicly about his research until his passing on April 24, 2021.

Related Profiles

Nancy Bartlit

Los Alamos, NM

Nancy Bartlit is the former president of the Los Alamos Historical Society and co-author of Silent Voices of World War II: When Sons of the Land of Enchantment Met Sons of the Land of the Rising Sun.

Jim Walther

Jim Walther is the director of the National Museum of Nuclear Science and History in Albuquerque, NM.

Dr. Ruth Patrick

Dr. Ruth Patrick was an American botanist and limnologist who studied the effects of pollution in water ways.

Joanna McClelland Glass

Washington, DC

Joanna McClelland Glass is a playwright best known for her play, Trying, based on her relationship with Francis Biddle, who was the United States Attorney General under FDR and chief judge at the Nuremberg Trials.