4. Louis Slotin
On 1946, Louis Slotin experimented with a plutonium core and two beryllium half-spheres to simulate first steps of fission reaction. He maintained the separation between two beryllium half-spheres using a screwdriver and it slipped from his right hand. When the upper half of beryllium fell, a critical reaction was triggered; the ionization was so intense that the air inside his laboratory glowed blue. Slotin died nine days later due to lethal exposure to neutron radiation. It was rumored that his body was transported and buried inside a lead coffin to prevent exposing others with radiation.
