1938 December - Enrico Fermi receives the Nobel prize for the discovery of transuranic elements (actually fission of uranium) and departs for the "new world." More »
December 22, Hahn and Strassmann (later Meiter and Frisch) conclude that the identification of barium implies that the uranium nucleus has been fissioned by neutrons. More » 1941 December 6 - The Manhattan Project Begins. More » 1942 December 2 - First nuclear chain reaction at Chicago's Stagg Field by Enrico Fermi. More » 1946 December 31 - Atomic Energy Commission (AEC) takes over nuclear weapons program from the U.S. Army. More » 1953 December 8 - President Eisenhower proposes "Atoms for Peace". More » 1979 December 26 - U.S.S.R. invades Afghanistan; SALT II Treaty removed from consideration by the Senate. More » 1986 December - First 10 MX/Peacekeepers missiles become operational. More » 1987 December 8 - Reagan and Gorbachev sign the INF Treaty. More » 2001 December 13 - U.S. withdraws from the Anti-Ballistic Missile Treaty. More » 2003 December 19 - Libya gives up it nuclear weapons program. 2010 December 22 - The United States' Senate Approves of New START. More »