One September morning in 1983, Lt. Col. Stanislav Petrov, a 44-year-old commanding officer with the Soviet Union's Air Defense Forces, saved the world from erupting into nuclear war.

According to the New York Times, Petrov died on May 19 at age 77, but news of his death was widely unrecognized at the time.

Here are five things to know about Stanislav Petrov, “The man who saved the world”:

His quiet death

Petrov reportedly died at his home in the Moscow suburb of Fryazino from hypostatic pneumonia.

According to the New York Times, he lived at his Fryazino home alone on a pension.

Petrov’s death was confirmed by German political activist Karl Schumacher, who tried to contact him on Sept. 9 to wish him a happy birthday.

Petrov's son Dmitri picked up the phone instead, informing Schumacher that his father had died in May, NPR reported.

Schumacher became a friend of Petrov’s in 1998 when, after learning of Petrov’s role during the Cold War, he traveled to Russia to meet him.

How did Petrov “save the world?”

On Sept. 26, 1983, Oko ( the Soviet Union’s early-warning satellite system for nuclear attack) detected that the United States had launched five ballistic missiles, all headed toward the USSR.

As the alarms went off and screens flashed the word “LAUNCH,” Petrov, who was just a few hours into his shift as duty officer at command center Serpukhov-15, remained calm.

"For 15 seconds, we were in a state of shock," he told the Washington Post in 1999. "We needed to understand, 'What's next?'"

It was Petrov’s gut feeling that led him to believe the launch reports were probably false.

“When people start a war, they don't start it with only five missiles,” he remembered thinking. “You can do little damage with just five missiles.”

He said his decision to stand down, the New York Times reported, was “at best, a ‘50-50’ guess.”

And, as Wired Magazine put it in 2007, "he hoped to hell he was right."

That gut feeling and Petrov's calm, common-sense analysis saved the world from potential catastrophe.

Read more here.
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