On This Date in 1983, Stanislav Petrov Single-Handedly Prevented Nuclear War

On September 26, 1983, the world came very close to nuclear war. Shortly after midnight, alarms inside Serpukhov-15—a bunker in Moscow where the Soviet Union monitored its satellites over the United States—began to go off. The satellites had detected the launch of an intercontinental ballistic missile from a base in the United States. Then the system reported that five missiles had been launched and were heading toward the Soviet Union from the U.S.

Lieutenant Colonel Stanislav Petrov, who was on duty that night, had no way of knowing that it was a false alarm: The satellites had mistaken the reflections of sunlight off high-altitude clouds as a missile launch. He had only a few minutes to determine if this was a genuine attack. In that case, Soviet protocol was an immediate counterattack.

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