Time Periods

	1890s-1939: Atomic Discoveries
	1939-1942: Early Government Support
	1942: Difficult Choices
	1942-1944: The Uranium Path to the Bomb
	1942-1944: The Plutonium Path to the Bomb
	1942-1945: Bringing It All Together
	1945: Dawn of the Atomic Era
	1945-present: Postscript -- The Nuclear Age

Comprehensive List of Events

1890s-1939: Atomic Discoveries A Miniature Solar System, 1890s-1919 Exploring the Atom, 1919-1932 Atomic Bombardment, 1932-1938 The Discovery of Fission, 1938-1939 Fission Comes to America, 1939 1939-1942: Early Government Support Einstein's Letter, 1939 Early Uranium Research, 1939-1941 Piles and Plutonium, 1939-1941 Reorganization and Acceleration, 1940-1941 The MAUD Report, 1941 A Tentative Decision to Build the Bomb, 1941-1942 1942: Difficult Choices More Uranium Research, 1942 More Piles and Plutonium, 1942 Enter the Army, 1942 Groves and the MED, 1942 Picking Horses, November 1942 Final Approval to Build the Bomb, December 1942 1942-1944: The Uranium Path to the Bomb Y-12: Design, 1942-1943 Y-12: Construction, 1943 Y-12: Operation, 1943-1944 Working K-25 into the Mix, 1943-1944 The Navy and Thermal Diffusion, 1944 1942-1944: The Plutonium Path to the Bomb Production Reactor (Pile) Design, 1942 DuPont and Hanford, 1942 CP-1 Goes Critical, December 2, 1942 Seaborg and Plutonium Chemistry, 1942-1944 Final Reactor Design and X-10, 1942-1943 Hanford Becomes Operational, 1943-1944

1942-1945: Bringing It All Together Establishing Los Alamos, 1942-1943 Early Bomb Design, 1943-1944 Basic Research at Los Alamos, 1943-1944 Implosion Becomes a Necessity, 1944 Oak Ridge and Hanford Come Through, 1944-1945 Final Bomb Design, 1944-1945 Atomic Rivals and the ALSOS Mission, 1938-1945 Espionage and the Manhattan Project, 1940-1945 1945: Dawn of the Atomic Era The War Enters Its Final Phase, 1945 Debate Over How to Use the Bomb, Late Spring 1945 The Trinity Test, July 16, 1945 Safety and the Trinity Test, July 1945 Evaluations of Trinity, July 1945 Potsdam and the Final Decision to Use the Bomb, July 1945 The Atomic Bombing of Hiroshima, August 6, 1945 The Atomic Bombing of Nagasaki, August 9, 1945 Japan Surrenders, August 10-15, 1945 The Manhattan Project and the Second World War, 1939-1945 1945-present: Postscript -- The Nuclear Age Informing the Public, August 1945 The Manhattan Engineer District, 1945-1946 First Steps toward International Control, 1941-1945 Search for a Policy on International Control, 1945 Negotiating International Control, 1945-1946 Civilian Control of Atomic Energy, 1945-1946 Operation Crossroads, July 1946 The VENONA Intercepts, 1946-1980 The Cold War, 1945-1990 Nuclear Proliferation, 1949-present

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