The Bhopal gas tragedy killed more people. The Soviet Union’s nuclear tests in Semipalatinsk irradiated a larger area over a longer period. Why then has the Chernobyl disaster endured so pronouncedly in the popular imagination?

During a flawed safety test, the nuclear reactor at the heart of the Chernobyl disaster entered an unstable state, culminating in explosions at 1:23 a.m. on April 26, 1986. The first firefighters arrived at the plant within minutes, expecting an ordinary fire. By then, the reactor core had exploded. When the personnel climbed on the roof, they stepped on blast debris. They didn’t know what it really was.