Source Pravda.Ru

C o m m e n t a r y Main Orbit of World Cosmonautics

Forty years ago on Friday, February 14, an event took place which was not only one of the main landmarks in world cosmonautics, but also, without exaggeration, heralded an entirely new stage in the development of terrestrial civilisation. On February 14, 1963, the first ever American communications satellite in the Syncom series was successfully put into a stationary orbit.

Television programmes broadcast by, say, the US or Russia, which can be watched by practically everyone on the planet, no longer mention the fact that the beaming is via a satellite. Non-wire telephone communication throughout the world is today quite ordinary. The entire system of command and control of modern armies is built upon a satellite communication system, and even effective struggle against terrorism and in particular the possibility of catching bin Laden, connected above all with an operational exchange of intelligence, directly depends on communications satellites in fixed orbits.

The idea for developing communications satellites was born soon after the war, when the future famous American sci fi writer Arthur Clark, in an issue of the Radio World magazine for October 1945, unveiled his concept of a repeater communication station located at an altitude of 35,880 kilometres above the Earth.

Clark is credited with determining the height of the orbit at which the satellite is immobile relative to Earth. Such an orbit is called stationary /geostationary/ or Clark's orbit. When a satellite travels along a stationary orbit, it makes one revolution in 24 hours, i.e. in the time Earth completes its daily rotation. The satellite in the stationary orbit hurtling at a speed of approximately 3 kilometres per second will be permanently above a definite point on Earth's surface. In that way, as distinct from numerous communications satellites in low near-Earth orbits, only three optically or radio-interconnected craft symmetrically positioned in a stationary orbit can cover the whole globe.

But stationary satellites are a costly business, because to achieve a stationary orbit a powerful carrier rocket is required, also fitted out with a booster unit that ensures the transfer of the satellite from a low transfer orbit to a stationary one. Despite technical difficulties and expenses, however, all satellites in a stationary orbit without exception recoup themselves very quickly, because the world market of satellite communications keeps growing all the time.

First ever communication satellite Telstar-1 was launched by Americans, because of inadequate techniques, only into a low near-Earth orbit about 6,000 kilometres high on July 10, 1962.

Russia now has the world's largest state-operated system of satellite communications. It was set up in April 1965 by launching Molniya-series satellites into heavily elongated elliptic orbits with an apogee over the Northern Hemisphere. Each series included four pairs of satellites placed in orbit at an angular distance of 90 degrees. In the mid-70s the family of communications satellites was joined by "stationary" Raduga and Gorizont spacecraft, which made it possible to establish a round-the-clock link between ground stations.

Today, as part of Russia's comprehensive programme for the 2001-2005 period, whole aerial complexes are being developed, designed to operate in stationary orbits, such as the Triada mobile communication system, the Gals direct television broadcasting system, the fixed communication system, and NTV Express.

Interestingly enough, despite the seemingly difficult financial position of Russian cosmonautics, promising programmes are devised and deployed rather successfully, because they are funded mainly from extra-budgetary sources obtained from commercial launches of communications satellites into stationary orbits by powerful and dependable carrier rockets of the Proton family.

An "extra" billion came to Rosaviakosmos' way after the United States had rescinded in December 2000 its so-called quotas for launching into stationary orbit American communications craft by Russian carriers.

The restriction on launches /otherwise, quotas/ covered American-made satellites or spacecraft which incorporated American components. These satellites or their components required licences for export from United States territory. And since in the overall number of communications spacecraft more than half are American-manufactured satellites and about 40 per cent have American components, the US could fully control the market of launching services and dictate its terms. But the obvious economic advantages of Proton launchings induced the outgoing Clinton administration to abandon the restrictions. Today when the Space Shuttle programme has been "grounded" and it appears for a long time, demand for Russian heavy carrier rockets on the world market of satellite communications should rise sharply.

It looks as though the situation with Russian military space is righting too. Its core, in addition to intelligence satellites, is made up of orbital groupings of communications spacecraft - Kosmos vehicles of different modifications, and Globus and Raduga units. According to remarks by Deputy Defence Minister Alexei Moskovsky, made early in February, the 2003 state defence order for space troops allocates 30 per cent more funds than last year.

Such a rise in financing will expedite the putting into operation of the new Angara military complex at the Plesetsk cosmodrome, intended to launch facilities directly into stationary orbits. At present, launches are effected from Baikonur, on a contractual basis with Rosaviakosmos.

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