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Russia has no reconnaissance satellites in orbit
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| 8 May 2001 |
Phillip S Clark JDW Special Correspondent
London
Russia no longer has any photo-reconnaissance satellites in orbit following the return to earth of two satellites in recent weeks.
First to return was Cosmos 2372, which was de-orbited on 19 April after 207 days in orbit. Then Cosmos 2370 was de-orbited after a year in orbit on 3 May or 4 May.
The Russian photo-reconnaissance satellite programme has been running at a low level in recent years after the 1970s and 1980s when more than 30 launches would take place each year: in 1999 there was only one launch and in 2000 three launches took place.
Four types of photo-reconnaissance satellite are currently operated by Russia, three belonging to the Yantar family and one to the Orlets family. The Yantar-1KFT, codename Kometa, satellites are launched once every year or two and undertake missions to update topographic and mapping data maintained by the Ministry of Defence.
Flights usually last for about 45 days with a single descent vehicle, a modification of the original Vostok sphere, being recovered at the end of the mission, this containing the complete photographic package. In 1998, the Cosmos 2349 Kometa satellite undertook photographic surveys under the SPIN-2 programme for the USA.
The current close-look Yantar-4K2 satellites, codename Kobalt, are also now only launched every year or two. The satellites originally flew for a standard 60 days but the three most recent launches in 1997, 1998 and 1999 have seen lifetimes of 120 days. The Kobalt satellites have three re-entry vehicles. Two small film return capsules are carried which can return data while the main satellite continues to operate in orbit and at the end of the mission the conical main descent module is recovered with the camera system and remaining film.
The operational lifetime of satellites like Kometa and Kobalt are limited by the amount of film which can be carried and this is overcome with the Yantar-4KS1 Neman satellites. These return images digitally via radio link, either direct to Russian controllers when passing over Commonwealth of Independent States territory or via data relay satellites in the Potok system which are operating in geosynchronous orbit. Recent Neman satellites have operated in orbit for about a year, with the record-holder having remained in orbit for 419 days. With Neman, the lifetime is limited by the amount of propellant for in-orbit manoeuvring which can be carried.
During the 1980s, it looked as if the Soviet Union was moving towards a capability to maintain at least one Neman and one Kobalt satellite in orbit on a permanent basis, but financial cutbacks after the collapse of the Soviet system meant that this could not be maintained into the 1990s. During the period 28 September 1996 to 15 May 1997, Russia had no photo-reconnaissance satellites in orbit, the longest break since the programme began in 1962.
The most recent addition to the Russian family of photo-reconnaissance satellites is the Orlets-2 Yenissey which has only flown twice. The configuration of these satellites is not known, but they are believed to carry more than 20 film-return capsules. Both satellites in the series were de-orbited at a time which would have permitted part of the satellite to have been recovered, but in the case of the first satellite it is believed that the main structure came down over the Pacific Ocean, the 'graveyard' for the disposal of all large Russian satellites including the Mir space station.
While the Yantar-class satellites weigh 6.6 to 7 tonnes and are launched on the Soyuz-U vehicle, the 12 tonne Orlets-2 requires the much larger Zenit-2 launcher.
During 2000, the three launches were representatives of the Neman (Cosmos 2370), Yenissey (Cosmos 2372) and Kometa (Cosmos 2373) series. Cosmos 2372 returned after almost matching the lifetime seen on the first Yenissey mission of 221 days (Cosmos 2290). Cosmos 2370 spent a full 12 months in orbit before its recall.