-
1942
President Roosevelt approves production of the atomic bomb following receipt of a National Academy of Sciences report determining that a bomb is feasible. -
1942
President Roosevelt instructs the Army to take responsibility for construction of atomic weapons complex. The Army delegates the task to the Corps of Engineers. -
1942
The Army Corps of Engineers establishes the Manhattan Engineer District to develop and build the atomic bomb. Uranium isotope separation facilities are built at Oak Ridge, Tennessee; plutonium production reactors are built at Hanford, Washington; and a weapons laboratory is set up at Los Alamos, New Mexico. -
1942
Brigadier General Leslie R. Groves, head of the Manhattan Engineer District, selects Oak Ridge, Tennessee, site for facilities to produce nuclear materials. Isotope separation of uranium235 takes place in the gaseous diffusion plant built in the K-25 area of the site, in the electromagnetic plant in the Y-12 area, and in the liquid thermal diffusion plant. A pilot pile (reactor) and plutonium separation facility are built and operated at the X-10 area. -
1942
Groves selects Los Alamos, New Mexico, as site for separate scientific laboratory to design an atomic bomb. -
1942
Metallurgical Laboratory scientists led by Enrico Fermi achieve the first self-sustained nuclear chain reaction in pile constructed under the west grandstand at Stagg field in Chicago. -
1943
Groves selects Hanford, Washington, as site for full-scale plutonium production and separation facilities. Three reactors--B, D, and F--are built. -
1943
The Big Inch crude-oil pipeline is completed from the Texas oil fields to Pennsylvania. The line serves as a transportation alternative to tankers that are being sunk by German submarines. The line also supplies export petroleum to the East Coast so that the reduced number of tankers can meet the demands of the European war fronts with the shorter-haul distance across the Atlantic. -
1944
The Little Big Inch pipeline for refined petroleum products is completed from Texas to New Jersey. Like the Big Inch, it is built by a private company, War Emergency Pipelines, but owned by the Federal government. -
1944
Congress passes the Synthetic Liquid Fuels Act authorizing the Bureau of Mines to build energy research laboratories. -
1944
Congress in the Flood Control Act of 1944 confirms the authorization of the Southwestern Power Administration created by President Roosevelt through a series of Executive and Departmental orders. -
1945
President Roosevelt dies. Harry S. Truman becomes President. -
1945
Germany surrenders. -
1945
Los Alamos scientists successfully test a plutonium implosion bomb in the Trinity shot at Alamogordo, New Mexico. -
1945
The gun model uranium bomb, called Little Boy, is dropped on Hiroshima, Japan. -
1945
The implosion model plutonium bomb, called Fat Man, is dropped on Nagasaki, Japan. Five days later, Japan surrenders. -
1946
Bernard Baruch presents the American plan for international control of atomic research to the United Nations. The Soviet Union opposes the plan, rendering it useless. -
1946
President Truman signs the Atomic Energy Act of 1946 transferring Manhattan Project assets and responsibilities to the civilian Atomic Energy Commission. -
1947
In accordance with the Atomic Energy Act of 1946, all atomic energy activities are transferred to the newly created Atomic Energy Commission. -
1947
Ground is broken at the Brookhaven National Laboratory for the Graphite Research Reactor, the first reactor constructed for the sole purpose of exploring peaceful uses of the atom. -
1948
Soviet Union begins blockade of West Berlin. -
1949
Soviet Union detonates first atomic device -
1950
President Truman instructs the Atomic Energy Commission to expedite development of a thermonuclear weapon. -
1950
North Korea invades South Korea. The Korean War begins. -
1950
President Truman approves a $1.4 billion expansion of Atomic Energy Commission facilities to produce uranium and plutonium for nuclear weapons. -
1951
The Experimental Breeder Reactor No. 1 located at the National Reactor Testing Station near Arco, Idaho, produces the first electric power from a nuclear reactor. -
1952
The U.S. Atomic Energy Commission (AEC) detonates the first thermonuclear device, code-named "Mike," at Enewetak Atoll in the Pacific. The device explodes with a yield of 10.4 megatons. -
1953
Dwight D. Eisenhower is inaugurated President. -
1953
President Eisenhower delivers the “Atoms for Peace” speech at the United Nations launching efforts to develop peaceful uses of nuclear energy both at home and abroad.