The demon core, a 6.2-kilogram subcritical mass of plutonium, carries a haunting legacy in nuclear history. Originating during World War II as a potential fissile core for an early nuclear bomb within the Manhattan Project, its story took a dramatic turn after Japan’s surrender.
Kept at the Los Alamos National Laboratory for further testing and potential future use, the demon core faced an unforeseen destiny. Tragically, it was involved in two nuclear accidents from August 1945 to late May 1946.
The first incident occurred on August 21, 1945, under the watch of physicist Harry Daghlian. While conducting neutron reflection experiments, Daghlian made a fatal error, resulting in a lethal dose of radiation.
In the second accident on May 21, 1946, physicist Louis Slotin was assembling two halves of a reflective beryllium sphere around the core when another catastrophic mishap occurred. Slotin displayed remarkable bravery but, regrettably, was also fatally exposed.
These two harrowing incidents earned the demon core its chilling nickname, and it was eventually melted down, bringing a somber end to its ominous tale.
