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Previous chapter: Sfera satellites

Second-generation geodetic system

A more advanced generation of geodesic satellites, code-named Musson Eridan, was inaugurated with the launch of Kosmos-1312 from Plesetsk on Sept. 30, 1981. (66) The development of the system designated Geo-IK was conducted during 1977 and 1978 at the 50th TsNII of Space Systems within the Ministry of Defense and the 29th NII VTS research institute. (76) Tsyklon-3 rockets carried the 1,530-kilogram Mussons into 1,480 by 1,525-kilometer orbits with an inclination 82-73.6 degrees.

Among its payloads, the Geo-IK satellite included a special lamp, which could produce a cascade of nine powerful flashes of light with a frequency of up to 55 times a day. Like a similar device on Sfera, the lamp was designed to facilitate highly accurate tracking photography of the satellite in the night sky.

The new system enabled the development of a global geodetic coordinate system, helped to clarify the shape of the Earth, its gravitational field and to establish geodesic relations between the different continents and islands around the globe. The information was expected to assist in the development of the USSR's global positioning system.

Although the operation of Soviet geodetic satellites had been well documented in the West since 1970s, the existence of the Geo-IK constellation was publicly acknowledged for the first time only in 1989. (99, 147)

The last Geo-IK satellite stopped working on February 5, 1999.

The Geo-IK system helped update the parameters of the Earth's model in 1986 and 1990, which were designated PZ-86 and PZ-90 respectively. A new coordinate system designated SK-95 was also developed. (455)



Geo-IK-1 (Musson) missions:

- Official name Launch End of operation
1 No name 1981 Jan. 22 (Launch vehicle failure)
2 Kosmos-1312 1981 Sept. 30 ?
3 Kosmos-1410 1982 Sept. 24 ?
4 Kosmos-1510 1983 Nov. 24 ?
5 Kosmos-1589 1984 Aug. 8 ?
6 Kosmos-1660 1985 June 14 1986 October
7 Kosmos-1732 1986 Feb. 11 1986 March
8 Kosmos-1803 1986 Dec. 2 1987 December
9 Kosmos-1823 1987 Feb. 20 1987 October*
10 Kosmos-1950 1988 May 30 1990 July
11 Kosmos-2037 1989 Aug. 28 1990 September
12 Kosmos-2088 1990 July 30 1993 March
13 Kosmos-2226 1992 Dec. 22 1993 July
14 Geo-IK 1994 Nov. 29 1995 July

*according to some sources, it exploded in orbit on Dec. 17, 1986. (147)

Next chapter: Geo-IK-2 (Musson-2) satellites

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Page author: Anatoly Zak; Last update: February 1, 2011

Page editor: Alain Chabot; Last edit: February 1, 2011

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A Musson (Geo-IK) satellite represented a second-generation of Soviet space-based geodesic systems. Copyright © 2001 Anatoly Zak