Manhattan Project

The Manhattan Engineer District (MED) was established by the U.S. Army Corps of Engineers in September 1942, early in WW II, with Brigadier General Leslie Groves in charge. The organization had an unprecedented objective: produce an atomic weapon before the Axis did.

Brigadier General Leslie R. Groves, named to head the Manhattan Engineer District in September 1942
Brigadier General Leslie R. Groves, named to head the Manhattan Engineer District in September 1942.

Today in WW II: 11 Jan 1942 Japanese occupy Kuala Lumpur, on the Malayan Peninsula.  More 
11 Jan 1944 Operation Pointblank: Allies attack German aeronautic facilities with a series of bombing raids to degrade the capabilities of the Luftwaffe.
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World War II Manhattan Project

Prior to his assignment to head the Manhattan Project, Gen. Groves' previous project was the construction of the Pentagon, the largest office building in the world at that time. Gen. Groves was given the top secret assignment to marshall the scientific and manufacturing resources of the U.S. to build an atomic weapon before any enemy could do so.

Within the vast enterprise of the Manhattan Project, three huge facilites were the major centers of work. More details of the history of each facility is on the page reached by clicking on these links:

The development of the bomb and its use in the war also required:

Overview of the Manhattan Project

No atomic weapon had ever been produced and even the theoretical basis was uncertain. There were two major issues: the design of the bomb and obtaining the explosive atomic material. Neils Bohr, the chief theoretician, had conjectured that the isotope of uranium U-235 would sustain the explosive chain reaction needed for a bomb. Nature is uncooperative, however, since only about 1% of the uranium found in uranium ore is U-235, while 99% is U-238, useless for an atomic bomb. The vast industrial site at Oak Ridge had the purpose of creating enough U-235 for bombs. Glen Seaborg, a University of California professior, discovered plutonium and found that its isotope P-239 was fissionable. The huge Hanford facility was established to extract plutonium as an alternate bomb material.

The design of the bomb, as well as the solution of many other theoretical and practical problems, was centered at the Los Alamos laboratory, headed by J. Robert Oppenheimer, the scientific director for the Manhattan Project, who created an unprecendented scientific and engineering team in the remote New Mexico desert. Two bombs were designed, one uranium based and one plutonium based. The final assembly and test of the first bomb at Trinity in July 1945 proved that all the work and investment of critial wartime resources had paid off. While it came too late to affect the war in Europe, two atomic bombs dropped on the Japanese cities Hiroshima and Nagasaki brought the Pacific war to a swift end.

J. Robert Oppenheimer, Enrico Fermi, and Ernest Lawrence, key figures in the Manhattan Project
(l. to r.) J. Robert Oppenheimer, Enrico Fermi, and Ernest Lawrence, key figures in the Manhattan Project.

The Pulitzer Prize winning book, The Making of the Atomic Bomb , by Richard Rhodes is highly recommended as the best general history of the Manhattan Project.

Find More Information on the Internet

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