Serpukhov-15 (Russian: Серпухов-15) is a military townlet near Kurilovo in Kaluga Oblast which is the location of the western control centre for Russia's Oko satellites.

[2] These give early warning of ballistic missile launches, mainly from the continental United States.

The older US-K satellites are in highly elliptical molniya orbits which give them coverage of the United States at certain times during the day.

[15][16] As the western control centre it can communicate with geosynchronous satellites in four of the seven reserved locations, those looking over the Atlantic.

[6] On 26 September 1983 the system suffered a major malfunction when it erroneously identified a launch of five Minuteman ICBMs in the United States.

[17] It appears that the system misidentified a particular set of circumstances including high clouds and the autumn equinox.

Colonel Stanislav Petrov, the officer on duty at the time, discounted the reports as the system had only recently become operational and the launches were not corroborated by early warning radar.