US-KMO (satellite)

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The US-KMO is a Soviet early-warning satellite tasked with the detection of rocket launches indicating an attack by ICBMs or SLBMs. It was originally intended that the OS-KMO would replace the earlier US-KS, which was useful for ICBM detection only, but it appears that the US-KMO was not successful, and the US-KS remains the primary Russian early-warning system to this day. The satellite is sometimes referred to as the Prognoz in the west, but this is the name of a science satellite program, although it appears the Prognoz spacecraft bus is used to form the US-KMO body.

[edit] Description

Published images of the US-KMO show a cylindrical main body oriented at right angles to the main detector. A long conical sunshield extends out from one end, consisting of several overlapping cylinders that fold for launch like a folding cup. Large solar panels extend from either side of the main body cylinder, resulting in a T-shaped spacecraft. Unlike the earlier US-KS, the US-KMO is launched from the Proton-K rocket, suggesting it is heavier than the US-KS, which was launched from the much smaller Molniya-M. Few other details are available.[1]

[edit] History

Development of the US-KMO started at NPO Lavochkin in 1979. Prior to this time the primary early-warning needs were focussed on the US's ICBM fleet, which had the accuracy needed to directly attack the Soviet strategic forces. The SLBM's were a secondary threat, they could not be launched alone without the Soviet counterforce surviving, making such an attack extremely unlikely. For this secondary role the existing Dnestr radar and similar systems would give adequate warning. However, the development of the Trident missile during the mid-1970s made the US SLBM force a serious threat to the Soviet counterforce on its own, one that neither the existing US-KS satellites or Dnestr radars was capable of detecting with the required lead times.

The new design would need to have a much wider detection area in order to be able to cover the possible launch sites of a Trident attack. The US-KS relied on having a "grazing angle" that allowed them to image the rockets against the blackness of space within a minute of launch. In order to do this they are positioned far to the east or west of the US missile fields, looking at them at a tangent to the Earth's surface. Although the same approach could be used against SLBMs as well, the large surface area of the potential ocean launch sites meant a large number of satellites would be required. Instead, the US-KMO was designed with new detector systems that could look directly down on the Earth, imaging the rocket plumes against the surface if need be. This allowed for a much wider-angle view, reducing the number of satellites needed. The USSR originally registered seven locations and transponder frequencies for the US-KMO network with the ITTU, stating that they would be occupied between 1984 and 1990.

However development appears to have been very slow, first as a result of continued problems with the US-KS, and later by the breakup of the Soviet Union. The first launch, Kosmos-1940, did not take place until 26 April 1988. Nine additional launches followed between 1991 and 2003, when launches ended.[2] Another potential issue was the lack of communications systems for the satellites over the Pacific, which required additional infrastructure to be built first. This appears to have never taken place, and the registered points remain unoccupied.

The system was first declared operational in 1988, at which point only two of the geostationary positions were occupied, one positioned to observe the US, and another the North Atlantic. Since then many of the satellites have broken down, and in 2002 only the one satellite remained operational, covering the US and some of the Atlantic.

[edit] References