Oko (Old ) is a Russian (previously

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

) missile defence

early warning An early warning system is a warning system that can be implemented as a Poset, chain of information communication systems and comprises sensors, Detection theory, event detection and decision support system, decision subsystems for early identi ...

programme consisting of

satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

s in Molniya and

geosynchronous orbit A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital ...

s. Oko satellites are used to identify launches of

ballistic missile A ballistic missile is a type of missile that uses projectile motion to deliver warheads on a target. These weapons are powered only during relatively brief periods—most of the flight is unpowered. Short-range ballistic missiles (SRBM) typic ...

s by detection of their engines' exhaust plume in

infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

light, and complement other early warning facilities such as

Voronezh Voronezh ( ; , ) is a city and the administrative centre of Voronezh Oblast in southwestern Russia straddling the Voronezh River, located from where it flows into the Don River. The city sits on the Southeastern Railway, which connects wes ...

, Daryal and

Dnepr radar Dnestr radar () and Dnepr radar (), both known by the NATO reporting name Hen House, are the first generation of Soviet space surveillance and early warning radars. Six radars of this type were built on the periphery of the Soviet Union starting ...

s. The information provided by these sensors can be used for the

A-135 anti-ballistic missile system The A-135 (NATO reporting name, NATO: ABM-4 Gorgon) is a Russian anti-ballistic missile system deployed around Moscow to intercept incoming warheads targeting the city or its surrounding areas. The system was designed in the Soviet Union and enter ...

which defends

Moscow Moscow is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia, standing on the Moskva (river), Moskva River in Central Russia. It has a population estimated at over 13 million residents with ...

. The satellites are run by the

Russian Aerospace Forces The Russian Aerospace Forces or Russian Air and Space Forces (VKS) comprise the air force, aerial, space force, space warfare, and Missile defense, missile defence Military branch, branches of the Armed Forces of the Russian Federation. It was ...

, and previously the

Russian Aerospace Defence Forces The Russian Aerospace Defence Forces (VVKO) () was a branch of the Russian Armed Forces responsible for aerospace defence, operation of Russian military satellites and the Plesetsk Cosmodrome. It was established on 1 December 2011 and dissolved ...

and

Russian Space Forces The Russian Space Forces () is the space force branch of the Russian Aerospace Forces. It was reestablished following the August 1, 2015 merger between the Russian Air Force and the Russian Aerospace Defence Forces, after the independent arm of s ...

. Since November 2015, it is being replaced by the new EKS system.

History

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 NPO Lavochkin (, OKB-301, also called Lavochkin Research and Production Association or shortly Lavochkin Association, LA) is a Russian aerospace company. It is a major player in the Russian space program, being the developer and manufacturer of t ...

. 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 Stanislav Yevgrafovich Petrov (; 7 September 1939 – 19 May 2017) was a lieutenant colonel of the Soviet Air Defence Forces who played a key role in the 1983 Soviet nuclear false alarm incident. On 26 September 1983, three weeks after the So ...

, on duty at the new control centre in

Serpukhov-15 Serpukhov-15 () is a military townlet near Kurilovo, Kaluga Oblast, Kurilovo in Kaluga Oblast which is the location of the western control centre for Russia's Oko satellites. These give early warning of ballistic missile launches, mainly from the ...

Moscow Oblast Moscow Oblast (, , informally known as , ) is a federal subjects of Russia, federal subject of Russia (an oblast). With a population of 8,524,665 (Russian Census (2021), 2021 Census) living in an area of , it is one of the most densely populate ...

, discounted the warning due to the newness of the system and the lack of corroboration from ground-based radar. The vast majority of the satellites launched (86 out of 100 as of March 2012) have been the first generation

US-K Upravlyaemy Sputnik Kontinentalny ( meaning ''Continental Controllable Satellite'') or US-K () is a series of Russian, previously Soviet Union, Soviet, satellites used to detect missile launches as part of the Oko system. It consists of a constell ...

satellites which operate in

molniya orbit A Molniya orbit ( rus, Молния, p=ˈmolnʲɪjə, a=Ru-молния.ogg, "Lightning") is a type of satellite orbit designed to provide communications and remote sensing coverage over high latitudes. It is a highly elliptical orbit with ...

s. Seven first generation satellites were launched into geosynchronous orbits, called

US-KS Upravlyaemy Sputnik Kontinentalny Statsionarny ( meaning ''Stationary Continental Controllable Satellite''), or US-KS (), also known as Oko-S, was a series of Soviet, and later Russian, missile detection satellites launched as part of the Oko () ...

, starting in 1975. A decree of 3 September 1979 led to the creation of the second generation satellites

US-KMO US-KMO (), an abbreviation for Upravlyaemy Sputnik - Kontinenty Morya Okeany () meaning ''Controllable Satellite - Continents, Oceans, Seas'' is a series of Russian, previously Soviet, satellites which are used to identify ballistic missile launch ...

which had their first launch in 1991. In total, 101 satellites have been launched. The US-K satellites, were launched by

Molniya-M The Molniya-M (, GRAU index: 8K78M) was a Soviet and Russian launch vehicle derived from the R-7 Semyorka Intercontinental ballistic missile (ICBM). The original 8K78 booster had been the product of a rushed development program and its launc ...

launch vehicle A launch vehicle is typically a rocket-powered vehicle designed to carry a payload (a crewed spacecraft or satellites) from Earth's surface or lower atmosphere to outer space. The most common form is the ballistic missile-shaped multistage ...

s with Blok 2BL upper stages from

Plesetsk Cosmodrome Plesetsk Cosmodrome () is a Russian spaceport located in Mirny, Arkhangelsk Oblast, near the town of Plesetsk, from which it takes its name. Until 2025 and the commissioning of the Andøya Space, Andøya base in Norway, it was the only operati ...

. The US-KS and US-KMO operate in geosynchronous orbits and were launched by

Proton A proton is a stable subatomic particle, symbol , Hydron (chemistry), H+, or 1H+ with a positive electric charge of +1 ''e'' (elementary charge). Its mass is slightly less than the mass of a neutron and approximately times the mass of an e ...

with DM-2 upper stages from

Baikonur Baikonur ( ; ) is a city in Kazakhstan on the northern bank of the Syr Darya river. It is currently leased and administered by the Russian Federation as an enclave until 2050. It was constructed to serve the Baikonur Cosmodrome with adminis ...

. The last US-KMO satellite (

Kosmos 2479 Kosmos 2479 ( meaning ''Cosmos 2479'') is a Russian US-KMO missile early warning satellite which was launched in 2012 as part of the Russian Aerospace Defence Forces' Oko programme. The satellite is designed to identify missile launches using in ...

) was launched on 30 March 2012 and the last US-K satellite (

Kosmos 2469 Kosmos 2469 ( meaning ''Cosmos 2469'') was a Russian US-K missile early warning satellite which was launched in 2010 as part of the Russian Space Forces' Oko programme. The satellite was designed to identify missile launches using optical teles ...

) on 30 September 2010. They are due to be replaced by a new system called EKS.

Debris

The first generation Molniya-type orbit Oko satellites launched between 1976 and 1983 were prone to disintegration, resulting in extensive

space debris Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...

. The reason they broke up was because they each carried an on-board explosive charge that would be used to destroy the satellite in the case of a malfunction. Unfortunately, control of the explosive charge was itself unreliable and it would often explode, rendering the satellite inoperative, while it was still under control. The design was eventually changed, and the explosive charge in Kosmos 1481 was the last to explode early.

Facilities

The system has two dedicated control centres. The western centre is at

() near Kurilovo outside Moscow () and the eastern centre is at

Pivan-1 Pivan-1 () is a military townlet near Komsomolsk-na-Amur in Khabarovsk Krai in the Russian Far East which is the location of the eastern control centre for Russia's Oko satellites. These give early warning of ballistic missile launches, mainly ...

() () in the Russian Far East. The centre at Serpukhov-15 burned down in 2001 which caused the loss of contact with currently orbiting satellites.

Notes

References

External links