On this day in 1946, nuclear scientist Louis Slotin was mortally injured while performing an experiment  known as “tickling the dragons tail”, which involves bringing a plutonium core to the first steps of a fission reaction. Colleagues were quick to bestow it the moniker of “Demon Core”, as the same core had caused the death of another scientist several months earlier in a similar experiment. If Homer Simpson comes to mind, you’re not far off.