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
Nagasaki National Peace Memorial Hall for the Atomic Bomb Victims across the surface of the water, symbolizing the victims. The foundation also tours internationally, holding anti-nuclear displays in cities around the world. The 2005 exhibition was held at the Peace Museum in Chicago, coinciding with the 60th anniversary of the bombing as well as a conference in New York which reviewed the Nuclear Non-Proliferation Treaty. In 2007, the exhibition was held in Guernica, Spain, which was heavily bombed by the Luftwaffe in April 1937. Nagasaki National Peace Memorial Hall for the Atomic Bomb Victims The is a commemorative monument in Nagasaki, Japan, situated next to its Atomic Bomb Museum. The