Oko

Oko (Russian: Око meaning Eye in old Russian), is a Russian (previously Soviet) missile defence early warning programme consisting of satellites in Molniya and geosynchronous orbits. Oko satellites are used to identify launches of ballistic missiles by detection of their engines' exhaust plume in infrared light, and complement other early warning facilities such as Voronezh, Daryal and Dnepr radars. The information provided by these sensors can be used for the A-135 anti-ballistic missile system which defends Moscow. The satellites are run by the Russian Aerospace Forces, and previously the Russian Aerospace Defence Forces and Russian Space Forces. As of December 2015, it is being replaced by the new EKS system.

Development of the Oko system began in the early 1970s under the design bureau headed by AI Savin, which became TsNII Kometa. The spacecraft element was designed by NPO Lavochkin. The first satellite was launched in 1972 but it was not until 1978 that the overall system became operational and 1982 before it was placed on combat duty. The system had a major malfunction in 1983 when it mistakenly identified sunlight on high altitude clouds as a missile attack. Stanislav Petrov, on duty at the new control centre in Serpukhov-15, Moscow Oblast, discounted the warning due to the newness of the system and the lack of corroboration from ground-based radar.

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