General History: The Manhattan Project to the Cold War
The first successful experiments in splitting a uranium atom occurred at the Kaiser Wilhelm Institute in Berlin in 1938. The first scientists in the United States to become aware of the dangerous potential associated with these experiments were a small group of refugee physicists who has fled Europe and the growing Nazi menace. If given sufficient time and resources, these scientists had little doubt that Nazi Germany would eventually use this information in the development of a potential super weapon – an atomic bomb. In the summer of 1939, three of these scientists, Leo Szliard, Eugene Wigner, and Edward Teller – convinced Albert Einstein of the potential danger of such a weapon, and also convinced him to write a letter to U.S. President Franklin Roosevelt, in an attempt to spur the government to action. This letter, eventually known as the Szliard-Einstein letter, resulted in the creation of a secret uranium committee on October 19,1939, which ultimately led to the creation of the Manhattan Project in August 13, 1942. In September 17. 1942 Colonel Leslie R. Groves is appointed head of the project and is then promoted to Brigadier general six days later. This set into motion an incredible series of events that ultimately resulted in the creation of three atomic bombs: Trinity (a prototype plutonium based atomic bomb this tested on July 16, 1945), Little Boy (a gun model uranium bomb that is dropped on Hiroshima on August 6, 1945), and Fat Man (an implosion model plutonium bomb) that is dropped on Nagasaki on August 9, 1945).
