Oko

For the Polish village, see Oko, Warmian-Masurian Voivodeship.

Oko

General Information
Manufacturer	TsNII Kometa NPO Lavochkin
Country of Origin	Soviet Union  Russia
Applications	Missile defence
Orbit regimes	Molniya
Production
Status	Operational
Built	86+
Launched	85
Lost	3
First launch	Kosmos 775 8 October 1975
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Oko (also called US-KS) (Russian: Око (УС-КС)) is a a Soviet and Russian satellite system, used to detect missile launches. It consists of a constellation of satellites, usually in molniya orbits, designated under the Kosmos (Cosmos) system. The satellites are built by the company NPO Lavochkin and are launched on Molniya-M rockets. Oko can be directly translated as the Russian word for eye.

History

Soviet era

The Oko (US-KS) early warning system was introduced in the Soviet Union in the 1970s, and declared operational in 1982. The satellites operated in molniya orbits with the parameters 600 x 39,700 km, 63 degrees and 718 minutes, passing over the Northern Hemisphere every 12 hours. They could spot the flame of a missile launch against the stellar background within 20 to 30 seconds, leaving enough time to launch a counterstrike. Propellant dumps from the Molniya-M a rocket's upper stage during Oko launches were connected to several UFO detections in Uruguay, Chile and Argentina after 1977. The system requires at least 4 functioning satellites in order for it to be effective. This was achieved in the 1980s, but the system often fell short of this goal.^[1]

Shortly after midnight Moscow time on 26 September 1983, one of the Oko satellites reported several US ICBMs being launched. This resulted in a major nuclear false alarm. The satellite reports were passed to the Oko control center, the Serpukhov-15 bunker outside in Kurilovo, outside Moscow, where Stanislav Petrov was in command at the time. Examining the reports, Petrov was convinced the reports were in error, and refused to report the "launches" to his superiors. As he later explained, "when people start a war, they don't start it with only five missiles."^[2] Later study suggests that the angle between the sun, the satellite and the missile fields resulted in reflections off high-altitude clouds that caused the reports. Geoffrey Forden published a report for the Cato Institute that identifies Kosmos-1382 as the most likely culprit for the false alarm.^[3]

Another early warning system, called the Prognoz, was launched in 1984. Its first satellite was Cosmos 2133. Prognoz was designed to use a 24-hour geosynchronous orbit to provide continuous coverage, in contrast to the 12-hour orbit used by Oko. It is unclear whether Prognoz was meant as a replacement for Oko or to supplement it. Some Oko-designated satellites were also adapted to use a 24-hour orbit.^[1]

Russian Federation

After the dissolution of the Soviet Union, the rate of launches decreased, but Russia remained committed to the program. A fully functioning constellation with 5 satellites was restored in 2001, but a fire in May 2001 in the Oko control facility at Kurilovo (Kaluga Region) reduced the number of operational satellites to 2. A further satellite was launched in the same year. Between 2002 and 2006 there were no Oko launches, until another Oko satellite, designated Cosmos 2422, was launched in July 2006.^[1]

In 2006, Russia had one operational US-KMO Prognoz (Cosmos 2379) satellite and four US-KS Oko satellites (Cosmos 2422, Cosmos 2393, Cosmos 2351, Cosmos 2368).^[1]

Satellites

The Oko satellites are drum-shaped, 2 meters long and with a diameter of 1.7 m. They weigh 1,250 kilograms without fuel and 2,400 kilograms when fully loaded. They have a 350-kg infrared telescope pointing toward Earth, with a 4-m conical sunshield and an instrument bus. The telescope, which is the satellites' main instrument, is able to detect radiation from ascending missiles. Two solar panels provide a total of 2.8 kW of power. There are also several smaller, wider-angle telescopes to supplement the main instrument. The satellites have 16 liquid fuel engines for altitude control and 4 for manouvering.^[1]

The system requires at least 4 satellites to be fully functional. The danger of false alarms increases when there are fewer than 4 satellites in orbit, due to the inability to double-check a detection.^[1]

The satellites are built by NPO Lavochkin and launched with Molniya-M rockets. The advantages of Oko include that the system is reliable and well-established, and that it uses the relatively inexpensive (but now discontinued) Molniya launcher.^[1]

References

1. ^ ^{a b c d e f g} Harvey, Brian (2007). "Military programs". The Rebirth of the Russian Space Program (1st ed.). Germany: Springer. ISBN 9780387713540. 
2. ^ False Alarms on the Nuclear Front
3. ^ Geoffrey Forden (May 3, 2001). "Reducing a Common Danger: Improving Russia's Early-Warning System". Cato Policy Analysis No. 399.