Stanislav Yevgrafovich Petrov (Russian: Станисла́в Евгра́фович Петро́в; born c. 1939) is a retired lieutenant colonel of the Soviet Air Defence Forces. On September 26, 1983, he was the duty officer at the command center for the Oko nuclear early-warning system when the system reported a missile being launched from the United States. Petrov judged that the report was a false alarm.^[1] This decision is credited with having prevented an erroneous retaliatory nuclear attack on the United States and its NATO allies, which would have likely resulted in large-scale nuclear war. Investigation later confirmed that the satellite warning system had malfunctioned.

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