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
Hiroshima National Peace Memorial Hall for the Atomic Bomb Victims Hiroshima National Peace Memorial Hall for the Atomic Bomb Victims Hiroshima National Peace Memorial Hall for the Atomic Bomb Victims is one of the National Memorial Halls in Hiroshima, Japan. The Hall was founded by the Japanese national government to mourn the atomic bomb victims in 2002. It was designed by Kenzo Tange. There is another National Peace Memorial Hall for the Atomic Bomb Victims in Nagasaki built for the same purpose. The Hall is in Hiroshima Peace Memorial Park near Hiroshima Peace Memorial across the "Motoyasu River" by "Motoyasu Bridge". The Hall curators are collecting atomic bomb memories and