Soviet Colonel who prevented 1983 nuclear response

MOSCOW, RUSSIA - MARCH 19: Former Soviet Colonel Stanislav Petrov sits at home on March 19, 2004 in Moscow, Russia. Petrov was in charge of Soviet nuclear early warning systems on the night of September 26, 1983, when a false "missile attack" signal appeared to show a U.S. nuclear launch and decided not to retaliate. He is feted by nuclear activists as the man who "saved the world" by determining that the Soviet system had been spoofed by a reflection off the earth. (Photo by Scott Peterson/Getty Images)