The Manhattan Project, An Interactive History Home The Manhattan Project, An Interactive History Home Department of Energy Home Office of History and Heritage Resources Home DOEHome
J.R. Oppenheimer and General Groves
Events People Places Processes Science Resources

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


Eric Jette, Charles Critchfield, and J. Robert Oppenheimer, Los AlamosBRINGING IT ALL TOGETHER
(1942-1945)
Events > Bringing It All Together, 1942-1945

No matter how much enriched uranium and plutonium might be produced at Oak Ridge and Hanford, it would all come to nothing if workable weapon designs could not be developed in time.  To this end, in late 1942 Leslie Groves established a bomb research and development laboratory at Los Alamos in the remote mountains of northern New Mexico.  The early work at Los Alamos concentrated primarily on defining the problems that needed to be solved.  Basic research on a variety of theoretical issues continued throughout 1943.  By 1944, it had become clear that, while a simple and reliable "gun-type" design could be used for a uranium bomb, the considerably more complicated implosion method would be required to produce a plutonium weapon.  With the successful Leslie Groves and J. Robert OppenheimerAllied landings in France on "D-Day," June 6, 1944, the war in Europe appeared to be entering its final phase.  Germany ceased to be the primary intended target.  General Groves and his advisers turned their sights on Japan, and the rush was on to complete the atomic bomb in time to end the war in the Pacific.   

Everything began to come together in the first months of 1945.  Oak Ridge and Hanford produced enough enriched uranium and enough plutonium for at least one bomb using each.  At Los Alamos bomb designs were finalized, and by the spring preparations had begun for the testing and use of the world's first nuclear weapons.  Meanwhile, word reached the Manhattan Project from the ALSOS mission that Germany was not close to completing an atomic bomb.  At the same time, espionage at Los Alamos was delivering critical weapon design information to the Soviet Union.

To learn more about any of these events associated with bringing together all the various aspects of nuclear weapons development, choose a web page from the menu below.  To continue with a quick overview of the Manhattan Project, jump ahead to the description of the "Dawn of the Atomic Era, 1945."

Previous    Next


Sources and notes for this page.

The text for this page is original to the Department of Energy's Office of History and Heritage Resources.  The photograph of the "Tech Area" at Los Alamos is courtesy the Los Alamos National Laboratory.  The photograph of Eric Jette, Charles Critchfield, and Robert Oppenheimeris reprinted in Los Alamos Scientific Laboratory, Los Alamos: Beginning of an Era, 1943-1945 (Los Alamos: Public Relations Office, Los Alamos Scientific Laboratory, ca. 1967-1971), 20.  The photograph of Leslie Groves and Oppenheimer is courtesy the Department of Energy.

Home | History Office | OpenNet | DOE | Privacy and Security Notices
About this Site | How to Navigate this Site | Note on Sources | Site Map | Contact Us