Thin Man (nuclear bomb) Thin Man (nuclear bomb) "Thin Man" was the code name for a proposed plutonium gun-type nuclear bomb using plutonium-239 which the United States was developing during the Manhattan Project. They aborted its development when they discovered that the spontaneous fission rate of their nuclear reactor-bred plutonium was too high for use in a gun-type design, due to the high concentration of the isotope plutonium-240. In 1942, prior to the Army taking over wartime atomic research, Robert Oppenheimer held conferences in Chicago in June and Berkeley, California, in July at which various engineers and physicists discussed nuclear bomb design issues. A
Bulletin of the Atomic Scientists to war meant. The "Bulletin" contributors believed the atom bomb would only be the first of many dangers. The aim of the "Bulletin" was to carry out the long, sustained effort of educating people about the realities of the scientific age. The "Bulletin of the Atomic Scientists" seeks to educate citizens, policy makers, scientists, and journalists by providing non-technical, scientifically sound and policy-relevant information about nuclear weapons, climate change, and other global security issues. The "Bulletin" also serves as a reliable, high-quality global forum for diverse international opinions on the best means of reducing reliance on nuclear weapons. Since its