Gorizont

Gorizont

Gorizont on a 1991 Soviet stamp
Names	Горизонт Horizon 11F662
Mission type	Communications
Operator	Russian Satellite Communications Company (RSCC)
Mission duration	3 years (planned)
Spacecraft properties
Spacecraft	Gorizont
Bus	KAUR-3
Manufacturer	NPO PM (ISS Reshetnev)
Launch mass	2,110 kg (4,650 lb)
Start of mission
Launch date	1978 - 2000
Rocket	Proton
Launch site	Baikonur
Contractor	Khrunichev
Orbital parameters
Reference system	Geocentric orbit
Regime	Geostationary orbit
Transponders
Coverage area	Soviet Union, Russia
Gorizont constellation

Gorizont (Russian: Горизонт, lit. 'horizon'), GRAU index 11F662, was a series of 35 Russian, previously Soviet, geosynchronous communications satellites launched between 1978 and 2000. The program was started in order to develop a satellite system to relay coverage of the 1980 Olympic Games from Moscow. The first four satellites were originally launched for this sole purpose.^[1] Following this, the Gorizont system was integrated into the YeSSS Unified Satellite Communication System,^[1] and was used to relay both civilian and military communications. From 1988 onwards, the satellites were also used in support of the Okean program.^[1]  

Gorizont satellites were based on the KAUR-3 satellite bus, which provided three-axis stabilisation, and liquid maneuvering engines.^[1] The Gorizont satellite constellation was replaced by the Ekspress constellation. The first satellite Gorizont-11L was launched on 19 December 1978 and the last satellite launched was Gorizont No.45L on 6 June 2000.