1. The Making of the Atomic Bomb Trinity Test, July 16, 1945

2. Scientific Background Discovery of Nuclear Fission, 1938-1939: Upon Meitner’s recommendation, Hahn and Strassman reexamined their earlier belief and came to the conclusion that barium, rather than radium, was created when bombarding uranium with neutrons Meitner and Frisch used liquid drop model to explain fission [http://dbhs.wvusd.k12.ca.us/webdocs/Chem- History/Meitner-Fission-1939.html]

3. Possibility of Bomb Leo Szilard: chain reactions Fermi and Szilard experiment at Columbia U. Einstein’s letter to FDR, 1939 Uranium Committee Turning point: 1940 Peierls-Frisch calculation of small critical mass of arrived in the US in 1941

4. Research and Production FDR authorized large-scale uranium research the day before Pearl Harbor Manhattan Project: September 1942 when Gen. Leslie Groves took over Chicago Pile 1: Nuclear reactor under Fermi proved chain reaction in late 1942 Plutonium route Production sites: Oak Ridge and Hanford

5. Los Alamos: Assembling the Bomb J. Robert Oppenheimer as director Collaboration of scientists from many countries—democratic strength? Maintain production schedule Gun-type for uranium bomb Implosion for plutonium bomb Trinity test in July 1945 Scientists’ views on the making of the bomb

6. Science and the Bomb Big Science: team work, interdisciplinary nature, large, government funding, political dimensions Scientists’ social responsibility New pattern of both the support and use of science by governments