Enter the "demon core". Sitting at a sizeable 6.2 kilograms (13.7 pounds) and 8.9 centimeters (3.5 inches) in diameter, this spherical mass of radioactive plutonium (at the time named "Rhufus ...

As the 80th anniversaries of the twin nuclear accidents involving the demon core come into view in 2025 and 2026, one can't help but find it curious how some of the same conditions that started ...