World Nuclear Energy Day takes place tomorrow, marking the 81st anniversary of the day in 1942 when Enrico Fermi and his team achieved the first controlled, self-sustaining nuclear chain reaction with Chicago Pile-1. It also is the anniversary of the first commercial nuclear reactor reaching criticality—at Shippingport, Pa., on December 2, 1957.

The inaugural World Nuclear Energy Day, on December 2, will be a celebration of nuclear energy and the people who make it happen. As nuclear power is a leading source of clean energy across the globe, the day aims to remind us that clean energy enables healthy lives.

Click here to find out how some are observing World Nuclear Energy Day 2020.