One man's quick thinking and cool head saved the world from nuclear war, and many people may not have known who he was.
Stanislav Petrov was on duty in a secret command center outside Moscow in September 26, 1983 when a radar screen showed that five missiles had been launched by the US towards the Soviet Union.
This was during the height of the Cold War, just three weeks after the Soviet army had shot down a Korean passenger plane, killing all 269 people on board.
President Ronald Reagan had recently called the Soviet Union, an "evil empire" and had convinced Americans that they were plotting a surprise nuclear attack.
Protocol stated that they were to order a retaliatory strike, but the then 44-year-old lieutenant had a gut instinct to ignore protocol this time, because he believed it was a false alarm.
“The siren howled, but I just sat there for a few seconds, staring at the big, back-lit, red screen with the word ‘launch’ on it,” he told the BBC’s Russian Service in 2013. “All I had to do was to reach for the phone; to raise the direct line to our top commanders.”
Instead of calling for a retaliating strike, which would start a third world war, he opted to follow his gut and and called in a malfunction in the early warning system. He later admits, that at the time, he wasn't sure if it was the right call or not.
"I had all the data [to suggest there was an ongoing missile attack]. If I had sent my report up the chain of command, nobody would have said a word against it," he said.
There were no rules about how long they were allowed to think before they launched their strike, according to Petrov. With 120 of his comrades around him waiting for a decision, the air was heavy with anticipation.
"I could see that everyone was looking at me. Some have turned their heads. Some are on their feet. I can see surprise and a feeling close to panic.
For a few seconds he didn't know what to do.
"All I had to do was to reach for the phone; to raise the direct line to our top commanders - but I couldn't move. I felt like I was sitting on a hot frying pan."