Franklin Delano Roosevelt11 October 1939
Roosevelt authorizes the creation of the Advisory Committee on Uranium. Economist Alexander Sachs meets with President Roosevelt and delivers the Einstein-Szilard letter
United States · Warfare / Nuclear. Chronological records rendered directly from the World History Database.
Roosevelt authorizes the creation of the Advisory Committee on Uranium. Economist Alexander Sachs meets with President Roosevelt and delivers the Einstein-Szilard letter
Economist Alexander Sachs meets with President Roosevelt and delivers the Einstein-Szilard letter
First meeting of the Uranium Committee, headed by Lyman Briggs of the National Bureau of Standards, 6000 dollars is budgeted for neutron experiments
President Franklin Roosevelt calls on Lyman Briggs of the National Bureau of Standards to head "The Uranium Committee" to undertake nuclear research, as a result of the Einstein-Szilard letter
Conclusive discovery of plutonium by Glenn Seaborg and Arthur Wahl
Vannevar Bush creates the Office of Scientific Research and Development (OSRD)
A report by Arthur Compton and the National Academy of Sciences is issued which finds favorable the prospects of developing nuclear power production for military use
The MAUD Committee issues final detailed technical report on design and costs to develop a bomb, advance copy sent to Vannevar Bush who decides to wait for official version before taking any action
Bush takes MAUD report to Roosevelt who approves project to confirm MAUD's findings
Bush takes MAUD report to Roosevelt who approves project to confirm MAUD's findings
Vannevar Bush holds a meeting to organize an accelerated research project, managed by Arthur Compton, Harold Urey develops research into gaseous diffusion as uranium enrichment & Ernest Lawrence investigates separation methods
Organises accelerated American uranium research.
Vannevar Bush holds a meeting to organize an accelerated research project, managed by Arthur Compton, Harold Urey develops research into gaseous diffusion as uranium enrichment & Ernest Lawrence investigates separation methods
Vannevar Bush holds a meeting to organize an accelerated research project, managed by Arthur Compton, Harold Urey develops research into gaseous diffusion as uranium enrichment & Ernest Lawrence investigates separation methods
Vannevar Bush holds a meeting to organize an accelerated research project, managed by Arthur Compton, Harold Urey develops research into gaseous diffusion as uranium enrichment & Ernest Lawrence investigates separation methods
First meeting of the OSRD sponsored S-1 project, dedicated to developing fission weapons
OSRD research includes radar, guided missiles and fission weapons.
Groves appoints Oppenheimer to head the project's secret weapons laboratory
Groves appoints Oppenheimer to head the project's secret weapons laboratory
Robert Oppenheimer convenes a summer conference at the University of California, Berkeley to discuss the design of a fission bomb, Edward Teller brings up the possibility of a hydrogen bomb as a major point of discussion
At a meeting of the S-1 Executive Committee, it is decided that a centralized laboratory should be established to study fast neutrons, code-named "Project Y"
Takes command of the Manhattan Project.
Colonel Leslie Groves is assigned command of the Manhattan Engineering District
Groves purchases 52,000 acres (210 km) of land in Tennessee for "Site X", which will become the Oak Ridge, Tennessee laboratory and production site
The Manhattan Project is given permission to use the highest wartime priority rating by the War Production Board
Leslie Richard Groves appoints Robert Oppenheimer to coordinate the scientific research of the project at the "Site Y" laboratory
Leslie Richard Groves appoints Robert Oppenheimer to coordinate the scientific research of the project at the "Site Y" laboratory
Groves and Oppenheimer visit Los Alamos, New Mexico and designate it as the location for "Site Y
Groves and Oppenheimer visit Los Alamos, New Mexico and designate it as the location for "Site Y
A constructed graphite pile is designed to produce weapons-grade plutonium.
A team led by Enrico Fermi, for whom Fermilab is named, initiate the first artificial self-sustaining nuclear chain reaction in an experimental nuclear reactor named Chicago Pile-1.
Chicago Pile-1, the first nuclear reactor goes critical at the University of Chicago under the leadership and design of Enrico Fermi.
Completes the construction of a nuclear reactor at the University of Chicago.
Leads a team which creates the first controlled nuclear reaction.
Starts the first nuclear chain reaction. Completes the construction of a nuclear reactor at the University of Chicago. A constructed graphite pile is designed to produce weapons-grade plutonium
Theorists Hans Bethe, John Van Vleck, Edward Teller, Felix Bloch, Emil Konopinski, Robert Serber, Stanley S. Frankel, and Eldred C. Nelson (the latter three all former students of Oppenheimer) quickly confirm that a fission bomb is feasible
Theorists Hans Bethe, John Van Vleck, Edward Teller, Felix Bloch, Emil Konopinski, Robert Serber, Stanley S. Frankel, and Eldred C. Nelson (the latter three all former students of Oppenheimer) quickly confirm that a fission bomb is feasible
Arthur Compton organizes the University of Chicago Metallurgical Laboratory in early 1942 to study plutonium and fission piles (primitive nuclear reactors)
Groves appoints Oppenheimer to head the project's secret weapons laboratory. From 1942-1946 under the control of the US Army Corps of Engineers, under the administration of General Leslie R. Groves
Groves appoints Oppenheimer to head the project's secret weapons laboratory. Theorists Hans Bethe, John Van Vleck, Edward Teller, Felix Bloch, Emil Konopinski, Robert Serber, Stanley S. Frankel, and Eldred C.
Nelson (the latter three all former students of Oppenheimer) quickly confirm that a fission bomb is feasible.
Oppenheimer and Robert Serber of the University of Illinois work on the problems of neutron diffusion (how neutrons moved in the chain reaction) and hydrodynamics (how the explosion produced by the chain reaction might behave). Arthur Compton asks theoretical physicist J.
Robert Oppenheimer convenes a summer conference at the University of California, Berkeley to discuss the design of a fission bomb, Edward Teller brings up the possibility of a hydrogen bomb as a major point of discussion.
Robert Oppenheimer of the University of California, Berkeley to take over research on fast neutron calculations-key to calculations about critical mass and weapon detonation
The scientific research is directed by American physicist J. Robert Oppenheimer
Oppenheimer and Robert Serber of the University of Illinois work on the problems of neutron diffusion (how neutrons moved in the chain reaction) and hydrodynamics (how the explosion produced by the chain reaction might behave).
Theorists Hans Bethe, John Van Vleck, Edward Teller, Felix Bloch, Emil Konopinski, Robert Serber, Stanley S. Frankel, and Eldred C. Nelson (the latter three all former students of Oppenheimer) quickly confirm that a fission bomb is feasible.
Fermi at Los Alamos tests the world's third reactor, LOPO, the first aqueous homogeneous reactor, and the first fueled by enriched uranium
Successful test of explosive lens for Fat Man
Successful test of explosive lens for Fat Man
Second meeting of the Target Committee, at Los Alamos, which works to finalize the list of cities on which atomic bombs may be dropped
The joint work of the scientists at Los Alamos resulted in the first artificial nuclear explosion near Alamogordo on July 16, 1945, the site of which Oppenheimer named "Trinity". The first nuclear explosion, the "Trinity" test of an implosion-style plutonium-based nuclear weapon known as "the gadget", near Alamogordo, New Mexico
General Carl Spaatz is ordered to bomb one of the targets: Hiroshima, Kokura, Niigata, or Nagasaki as soon as weather permitted, some time after August 3
General Carl Spaatz is ordered to bomb one of the targets: Hiroshima, Kokura, Niigata, or Nagasaki as soon as weather permitted, some time after August 3
"Fat Man", an implosion-type plutonium-239 weapon, is used against the city of Nagasaki, Japan
The Smyth Report was the common name given to an administrative history written by physicist Henry DeWolf Smyth about the Allied World War II effort to develop the atomic bomb, the Manhattan Project
Oppenheimer resigns as director of Los Alamos, and is succeeded by Norris Bradbury
Oppenheimer resigns as director of Los Alamos, and is succeeded by Norris Bradbury
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