On the night of September 25-26, 1983, 40 years ago, 44-year-old Soviet lieutenant and engineer Stanislav Petrov was on duty at a military base south of Moscow. His job was to monitor the activity of a Soviet warning system that was supposed to detect the possible launch of nuclear missiles by the United States. At a certain point, shortly after midnight, the system started ringing: as per protocol, Petrov should have immediately notified his superiors, who would have proceeded with the counterattack.
After almost a decade in which tensions between the two superpowers had decreased, for some years the Cold War had returned to a phase of more open hostilities. The alert level was therefore high, but Petrov decided to wait for further confirmation rather than immediately transmit the alert to his superiors. The confirmations did not arrive: there had been a malfunction in the system, which had caused a false alarm. If the Soviet Union had counterattacked, the situation would have escalated very quickly, possibly resulting in a nuclear conflict. The episode of that night went down in history as the accident of the autumnal equinox, and Petrov, because of his caution, is sometimes remembered as “the man who saved the world”, which is also the title of a Danish documentary dedicated to him in 2015.
The alarm system at the center of the incident was called Oko: it was developed starting in the 1970s and was designed as an early warning program to respond promptly to possible attacks. The system was composed of some satellites positioned in orbit with radars, capable of detecting missile launches from certain points under observation. The control center of the Oko system was located near Kurilovo, south of Moscow, in a bunker at the Serpukhov-15 military base.
On the night between 25 and 26 September, Petrov was responsible, who knew the Oko system very well and had to monitor the signals sent and warn the military leadership of any imminent missile attack against the Soviet Union. At that moment, in the event of an attack, it was highly probable that the Soviet Union would counterattack immediately: in 1983 tensions between the United States and the Soviet Union were particularly strong, also due to a series of episodes in the previous years.
Those were the years in which the Soviet Union and NATO, the military alliance that includes part of the Western countries, were engaged in difficult negotiations which only in 1987 led to the INF treaty (“Intermediate-Range Nuclear Forces Treaty”), a agreement that neither country could possess a certain type of nuclear missile. The treaty was arrived at after mutual deployments, between 1977 and 1983, of nuclear weapons in various points of Eastern Europe: in 1983 the Soviet Union abandoned the ongoing negotiations, which resumed two years later, in response to the deployment by of the United States of a series of missiles.
1983 was also the year of the Able Archer 83 exercise, carried out by NATO and mistaken by the Soviet Union for an attempted attack: the episode is remembered as one of the times we came closest to a nuclear war.
Shortly after midnight some sirens went off in the Oko control center and the word “LAUNCH” appeared on one of the screens: it signaled the departure of an intercontinental ballistic missile, and four others immediately after, from a military base in Malmstrom, Montana. The personnel on duty at the Russian base were alarmed, but according to some reconstructions the signal was also received with a certain degree of skepticism: partly because five missiles seemed too few to start a nuclear clash between the two superpowers, partly because Petrov, who had helped develop the Oko system software, knew that errors and malfunctions could occur.
Thirty years after that episode Petrov told the BBC that for some reason he couldn’t explain at the time he didn’t feel like notifying his superiors immediately. There were no formal rules on when to do this, but obviously in the case of an attack any second of delay could have enormous consequences: «All I had to do was pick up the phone to activate the direct line to our higher commanders, but not I could move. I felt like I was sitting on a hot pan.”
On other occasions Petrov spoke of the extreme stress of those moments, in which he had just a few minutes to make a decision with potentially enormous consequences, while the screen flashed, the sirens sounded and the other operators of the facility waited for directions on how to proceed.
There are different accounts of what exactly happened in the moments following the alarm. It seems that Petrov tried to restart the system, and after a few minutes the alarm stopped. Meanwhile, other Soviet radars, positioned not in orbit but on the ground, did not report any missiles. About twenty minutes later Petrov received confirmation that no missiles had been launched by the United States, and that if he had broadcast the alert he would have activated a series of operations that could have led to nuclear war.
Petrov was initially praised for how he handled the situation, but things changed shortly thereafter: he underwent extensive interrogation by Soviet authorities, the legitimacy of his decisions was questioned, and he never received recognition for having effectively avoided a nuclear confrontation . It seems that Oko’s malfunction was due to a particular alignment of sunlight reflected by the clouds and satellites in orbit, which would have triggered the alarm even in the absence of missiles.
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