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
Atomic Age people walked from Los Angeles to Washington DC in the Great Peace March for Global Nuclear Disarmament. There were many Nevada Desert Experience protests and peace camps at the Nevada Test Site during the 1980s and 1990s. On May 1, 2005, 40,000 anti-nuclear/anti-war protesters marched past the United Nations in New York, 60 years after the atomic bombings of Hiroshima and Nagasaki. This was the largest anti-nuclear rally in the U.S. for several decades. Atomic Age The Atomic Age, also known as the Atomic Era, is the period of history following the detonation of the first nuclear ("atomic") bomb, "Trinity",