THE MANHATTAN PROJECT

SUMMARY

• The Manhattan Project was a research and development project.
• It was started in the late 1930s in response to WWII.
• The project produced the first atomic bombs.
• By June 1944, the Manhattan Project employed some 129,000 workers.

LINCHPIN

• In August 1939, the U.S. received the Einstein-Szilárd letter.
• This letter warned of "extremely powerful bombs of a new type".
• It advised the U.S. to stockpile uranium ore.
• They advised the funding of Enrico Fermi.
• He researched nuclear reactions.

LOCATION

• The Manhattan Project's headquarters was in Manhattan initially (obviously).
• It was moved to Oak Ridge, Tennessee only a year after the project commenced.
• Most of the development occurred in Los Alamos, NM and Oak Ridge.
• The Los Alamos National Laboratory designed the actual bombs.

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GOVERNMENT INVOLVEMENT

• The project was kicked into gear after Pearl Harbor.
• The War Production Board got actively involved.
• President Roosevelt personally signed off on many of the documents.
• The Tennessee Valley Authority was crucial in bringing power to the Oak Ridge plant.
• Donald Nelson, president of the WPB, gave the project a high priority rating.

INTERNATIONAL AFFAIRS

• Roosevelt and Churchill initially agreed to work on development together.
• This didn't last because England payed none of the costs while still making demands.
• Many British scientists still helped with development, like James Chadwick and Niels Bohr.
• Prominent German physicists like Albert Einstein, Leó Szilárd, and Eugene Wigner were vital.

BLUEPRINTS

• J. Robert Oppenheimer from Berkeley was the head design researcher.
• Researched fast neutron calculations - the key to calculations of critical mass and weapon detonation.
• Brought together a team of genius physicists.
• They deduced that an atomic bomb was possible using uranium and newly discovered plutonium.

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URANIUM

• Uranium is crucial to building of the atomic bomb.
• Thousands of tons of uranium ore were mined or imported during The Manhattan Project.
• Mallinckrodt Incorporated in St. Louis turned the raw ore into highly pure uranium dioxide.
• Natural uranium consists mostly of a stable isotope with only a very small amount of the reactive isotope.
• The reactive isotope was then separated from the stable isotope to produce the uranium used in the bomb.

PLUTONIUM

• Plutonium was also used to make atomic bombs.
• It is found in small amounts in nature.
• However to obtain big amounts of it, it is made synthetically.
• It is made in a nuclear reactor by bombarding uranium with neutrons.
• The plutonium is then separated from the uranium.

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TRINITY TEST

• Physicists deduced that an unpredictable bomb like an atomic bomb would need to be tested.
• This test was codenamed "Trinity".
• The bomb was dropped near Alamogordo Army Airfield in New Mexico.
• The shock wave extended 100 miles and the mushroom cloud climbed 7.5 miles high.
• It was heard as far away as El Paso, Texas.

HIROSHIMA AND NAGASAKI

• Hiroshima: Uranium based bomb
• Blast equal to 13 kilotons of TNT
• 69% infrastructure destroyed, 7% damaged
• 80,000 people immediately dead, 70,000 injured
• Only 20,000 of the dead were Japanese soldiers

HIROSHIMA AND NAGASAKI

• Nagasaki: Plutonium based bomb
• Blast equal to 21 kilotons of TNT
• 44% infrastracture destroyed
• 40,000 killed immediately, 60,000 injured
• Only 150 of the dead were Japanese soldiers

THE WAR IS OVER