NPR Here and Now: 75 Years Ago, Scientists Conducted An Unprecedented Nuclear Experiment.

“Seventy-five years ago this week, scientists from the University of Chicago created the first controlled, self-sustained nuclear chain reaction, a feat that was essential in the development of an atomic bomb during World War II.

Enrico Fermi and his team of physicists secretly conducted the Chicago Pile 1 experiment on a squash court under the stands of a football stadium on Dec. 2, 1942. The anniversary of this unprecedented achievement comes as tensions escalate between the U.S. and North Korea, which launched a new ballistic missile on Tuesday.”