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For centuries, Russian rulers faced serious challenges in managing their domain -- the world's largest country spread from Baltic to the Pacific. In the 1960s, with the advent of space technology, the Soviet government for the first time had an opportunity to reach vast regions of the country with telephone communications and TV signals. In fact, for many Soviet citizens inhabiting rural areas of the country, the satellite TV was the only evidence of the coming Space Age. In 1961, OKB-1, the organization that built the world's first manned spacecraft, also started the development of a communications satellite. Although the Space Age had barely began, the idea of using orbital spacecraft for providing communications was not new. Arthur Clark, more famous for his sci-fi novels, is also credited for a prophetically accurate description of satellite communications in 1945. In his memo to the British Interplanetary Society, Clark wrote that if the spacecraft reaches the altitude of 35,880 kilometers over the Equator, it would need 24 hours to make a complete circle, and thus it will appear "hanging" to an observer from Earth. As a result, three spacecraft evenly spread in such orbit 120 degrees apart, could "hear" signals from anywhere on the planet. Molniya series Although western developers overwhelmingly adopted 24-hour (geostationary) orbit for practical missions of communications satellites, the Russian engineers chose a different approach. The limitations of available rocket power prompted OKB-1 to seek a less energy-consuming orbit suitable for communications. Resulting studies came up with a hugely elongated ellipse, whose apogee, or the highest point, would be over the northern hemisphere, providing but continuous "view" of the Russian territory. Such trajectories became known as Molniya (Lighting) orbits, after a long-lasting series of satellites the USSR had introduced in 1965. Soviet geostationary satellites As the Proton rocket came out of age at the beginning of the 1970s, its four-stage configuration born in the heat of the Moon Race was given a new job of opening a window for the USSR to the geostationary orbit. In March 1974, the Proton delivered the first Soviet satellite into the 24-hour orbit. In 1975 and 1976, a series of Raduga (Rainbow) and Ekran (Screen) satellites entered service over the Equator, providing communications for the Soviet military and civilian institutions. In 1979, a more capable Gorizont (Horizon) satellite was inaugurated. In the meantime, NPO Energia, looking for the passengers for its super-heavy Energia rocket, concieved a 18-ton communications platform, the largest communications satellite ever proposed. The project had never gone beyond paper stage. Post-Soviet satellite communications From mid-1960s and until the collapse of the USSR in 1991, NPO PM development center in a Siberian town of Zheleznogorsk, which inherited the Molniya project from OKB-1, had remained a sole provider of communications spacecraft for the nation. However, space funding crunch of the post-Soviet period, bred the competition from other Russian space enterprises who saw potentially lucrative market in the field of satellite communications. During the 1990s, NPO PM struggled to modernize an obsolete and underpowered fleet of Russian comsats with the new Express family, however many orbital positions the country reserved for its birds remained empty and were under threat of expiration under the international law. Yamal program In such climate, RKK Energia, previously specialized in prestigious but then severly underfunded field of manned space flight, pushed a privately financed project of communications satellite, known as Yamal. Thanks to its smaller size, two Yamals could ride a single Proton rocket, potentially increasing Russia's chances to fill its orbital positions. However RKK Energia's lobbying of the Russian government to adopt Yamal platform for its future orders under name Express-AYa proved fruitless. Express AM program Instead, NPO PM turned to western subcontractors for the supply of advanced communications payloads, in the effort to extend orbital life, power and communication capacity of the Express family. As of 2004, Russian Satellite Communications Organization planned to complete an orbital constellation of five Express-AM satellites in 2005. At the time the company oversaw a constellation of 15 satellites. Sesat The NPO PM also won an order from a the European conglomerate Eutelsat to build Siberian-European Satellite, or Sesat, which became the first communications spacecraft built by a Russian prime contractor for a Western customer. Overview of Russia's communications satellites:
Written and illustrated by Anatoly Zak; Last update: June 21, 2007 |
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