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Today in History - December 2

Nuclear Fission

On the afternoon of December 2, 1942, the Atomic Age began inside an enormous tent on a squash court under the stands of the University of Chicago’s Stagg Field. There, headed by Italian scientist Enrico Fermi, the first controlled nuclear fission chain reaction was engineered. The result—sustainable nuclear energy—led to creation of the atomic bomb and nuclear power plants—two of the twentieth century’s most powerful and controversial achievements.

“…the Italian Navigator has just landed in the New World…”

Coded telephone message confirming first self-sustaining nuclear chain reaction, December 2, 1942.

Four years earlier, Fermi had received the Nobel Prize for Physics. Like so many intellectuals who had left fascist Europe, Fermi came to the United States and worked at Columbia University.
Declaration of Intention, Number 27081, for Enrico Fermi [Application for U.S. Citizenship]. December 2, 1939. National Archives and Records Administration
Fermi learned from the Nobel Prize-winning physicist Niels Bohr about the findings of Lise Meitner. Meitner had worked in Germany with physicists Otto Hahn (Hahn later won the Nobel Prize in Chemistry) and Fritz Strassmann and had discovered the process of nuclear disintegration. She worked in the field of nuclear physics and chemistry with her nephew, Otto Frisch; they named the process fission. Fermi and the Hungarian physicist Leo Szilard (who left Hungary for Germany, then fled to London, before moving to the U.S.) realized that the first split or fission could cause a second, and so on–in a series of chain reactions expanding in geometric progression. Szilard and fellow Hungarian émigré Eugene Wigner persuaded Albert Einstein to write President Franklin D. Roosevelt and request that atomic research receive a high priority. In fact, Szilard was responsible for the establishment of the Manhattan Project.
Albert Einstein, c1945. Prints and Photographs Division
Preparing the nation for war, Roosevelt agreed. In December 1941, as the U.S. entered World War II, the project moved to Chicago where Fermi, Walter Zinn, Herbert Anderson, Arthur Compton, and Leo Szilard were the principal team members. Within four years, the Manhattan Project, supervised by J. Robert Oppenheimer, Compton, and Fermi, developed the atomic bomb.
Franklin D. Roosevelt to J. Robert Oppenheimer, June 29, 1943. Words and Deeds in American History: Selected Documents Celebrating the Manuscript Division’s First 100 Years. In this letter, the president thanks Oppenheimer and his colleagues for their ongoing secret atomic research.

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