German radiochemists Otto Hahn and Fritz Strassmann discover the process of fission in uranium
Glenn T. Seaborg’s research group at the University of California in Berkeley discovers plutonium.
Roosevelt establishes the Office of Petroleum Coordinator for National Defense
President Roosevelt approves production of the atomic bomb following receipt of a National Academy of Sciences report determining that a bomb is feasible.
Groves selects Los Alamos, New Mexico, as site for separate scientific laboratory to design an atomic bomb.
The gun model uranium bomb, called Little Boy, is dropped on Hiroshima, Japan.
President Truman signs the Atomic Energy Act of 1946 transferring Manhattan Project assets and responsibilities to the civilian Atomic Energy Commission.
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.
Soviet Union detonates first atomic device.
President Truman approves a $1.4 billion expansion of Atomic Energy Commission facilities to produce uranium and plutonium for nuclear weapons.
