Lt. Col. Stanislav Petrov was duty officer at Serpukhov-15, the secret bunker outside Moscow that monitored the Soviet Union’s early-warning satellite system, when the alarm bells went off shortly after midnight [on September 26, 1983]. One of the satellites signaled Moscow that the United States had launched five ballistic missiles at Russia. . . .

Sept. 26, 1983: The Man Who Saved the World by Doing … Nothing