history · 21 May 1946 · 78 years ago
Canadian Manhattan Project Louis Slotin accidentally set of a prompt critical reaction when he allowed two beryllium hemispheres to touch with a plutonium core in the center. He realized his mistake immediately and lifted the upper hemisphere with his left hand, averting disaster, but not before he received 2,100 rems of radiation. He was rushed to the hospital. The plutonium core involved in this accident was the same one in the accident with physicist Harry Daghlian in 1945.
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