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Konstantin Tsiolkovskiy
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Comsat and Intelsat

Comsat and Intelsat are two large organizations that provide satellite communication services, including worldwide television. Satellites are needed for very long-distance television, because television signals travel in straight lines and cannot curve around the Earth to reach distant receivers. If a transmitter lies below the horizon, its signals cannot be detected. It helps to place a receiving antenna atop a mountain, which allows it to “see” transmitters that are farther away. A satellite, thousands of miles above the Earth, flies far above the tallest mountains and can pick up signals from other continents. It can then transmit them to receiving antennas that are even farther distant.

The first such use of satellites to transmit television signals was achieved by the Telstar satellite, built by the firm of American Telephone and Telegraph (AT&T) and launched by the National Aeronautics and Space Administration (NASA) on July 10, 1962. This satellite provided the transatlantic link for the first historic transatlantic television transmission. With both the United States and Europe in view, its antenna picked up the signal from its centre in Maine, amplified it to increase its strength, and retransmitted it to a similar centre in France. Telstar also opened up the prospect of vast improvements in international telephone service. Some transatlantic phone cables were already operating, but they provided only a few hundred telephone circuits between North America and all of Europe. Satellites promised to expand this number enormously and to offer service across the Pacific as well.

Earlier, in July 1961, President John Kennedy had called for federal involvement in satellite communications. Thirteen months later, Congress passed the Communications Satellite Act. It established the Communications Satellite Corporation, known as Comsat, and chartered this company with responsibility for developing and controlling American activity in this field.

Telstar is considered by most observers probably to have ushered in the era of satellite communications.

The new law was aimed squarely at AT&T, a major corporation that operated much of the Nation's telephone system. AT&T was quite prepared to build additional Telstars and to establish a global satellite system on its own. But the Kennedy administration took the view that AT&T would use its power to squeeze out competitors.

The firm of Hughes Aircraft was among these competitors. Hughes manager Harold Rosen hoped for a system that could leap beyond Telstar. The Telstar satellite flew in a relatively low orbit, demanding a costly antenna that could swivel to track it as it moved across the sky. Rosen wanted to place a communications satellite in geosynchronous orbit, at an altitude of 22,300 miles (35,888 kilometres). This satellite would take 24 hours to circle the globe and would appear to hover motionless over a fixed location. The antennas on the ground then could be much simpler and less costly. They could be fixed in position and would not have to track a spacecraft as it changed position in the sky. Moreover, a satellite at that altitude could serve nearly half the Earth. Rosen sold the concept to the National Aeronautics and Space Administration (NASA), which called the satellite system Syncom. The first Syncom satellite operated as an experimental version and reached this high orbit in 1963.

By then the Comsat Corporation was in business, issuing shares of stock that were bought and sold on Wall Street. AT&T held 29 percent of these shares, which gave it a strong voice while leaving it well short of outright control. This assured the independence of Comsat, which proceeded to operate as a company in its own right. The Comsat board of directors had six members elected by AT&T and other large companies, six chosen by individual persons who had bought stock, and three appointed by the president of the United States. The board included George Meany, head of the AFL-CIO labor union, and Frederic Donner of General Motors.

In August 1964, 11 nations banded together to form the International Telecommunications Satellite Organization, or Intelsat. A board of directors whose votes were weighted to reflect the member countries' volume of communications traffic also governed this organization. By agreement, Comsat held more than half of the votes on the Intelsat board. An early initiative called for Intelsat to purchase its own satellite, and its governing board showed further independence from AT&T. Instead of turning to that firm, it purchased a version of Syncom from Hughes Aircraft.

Intelsat 1, also called Early Bird.

The new spacecraft, called Early Bird, took up a position high over the Atlantic Ocean in April 1965. Its television coverage opened with drama, as an American surgeon operated on a heart while fascinated colleagues in Europe looked over his shoulder. The NBC anchorman Chet Huntley teamed with his counterpart in London, Richard Dimbleby. A panel discussion, “Town Meeting of the World,” linked statesmen in New York, London, and Paris as they talked about the war in Vietnam.

Intelsat VI series spacecraft (one of five), weighing about 4.5 tons at launch and standing nearly 40 feet tall when deployed, is prepared for final testing at Hughes Aircraft Company in El Segundo, California.

Intelsat reached its goal of global coverage during 1969. By then it had three spacecraft hovering over the Atlantic and three over the Pacific. A seventh, high above the Indian Ocean, linked London and Tokyo at mid-year and completed the initial system. The satellites were upgraded versions of Early Bird, with each of them providing circuits for up to 1,200 simultaneous telephone conversations. Therefore each spacecraft had nearly three times the capacity of all the transatlantic cables in service as recently as 1965, but it still was not enough. Amid burgeoning demand, Hughes Aircraft built the Intelsat 4 series, with 4,000 and then 6,000 circuits in each satellite.

Even so, Intelsat faced competition. This took form in 1967, as France and West Germany agreed to develop a non-Intelsat communications satellite called Symphonie. In 1968, Symphonie project directors wrote to the head of NASA, Thomas Paine, asking him to place two of these European spacecraft into orbit using American launch vehicles. However, President Lyndon Johnson had set forth a policy calling for the Nation “to support development of a single global commercial communication satellite system” and to refuse to provide “launch services or other assistance…except for use in connection with the single global system.” Paine therefore turned down the European request. The French and Germans had no launch vehicles of their own and, for the moment, there was nothing they could do.

During the next three years, officials in Washington had a change of heart. European launchers now were in development, as their builders prepared to challenge the United States monopoly. A NASA paper noted that it was essential to assure the Europeans “that they are indeed partners and not puppets in an organization dominated by the U.S.” In 1971, Undersecretary of State U. Alexis Johnson wrote a letter in which he gave State Department approval to Symphonie, declaring that “we would expect to support it in Intelsat.” This opened the door to NASA, which launched the two Symphonie satellites in 1974 and 1975.

By then the Intelsat consortium was serving close to a hundred nations. The roster included bitter enemies, among them Israel and Egypt and India and Pakistan. It included some of the world's poorest nations: Haiti, Bangladesh, and much of Africa. As demand continued to grow, the capacity and weight of the spacecraft increased accordingly. Intelsat 3, which first flew in 1968, weighed 152 kilograms and provided 1,200 telephone circuits. Intelsat 4, with its 4,000 circuits, went into orbit only three years later. Yet even this was insufficient, for Intelsat 5, which flew in 1980, weighed more than two tons and provided 12,000 circuits in each spacecraft.

The Intelsat arrangements covered telephone service between and within nations, especially those where thin internal communications networks served large areas. The advent of satellite service made it possible for these countries to leap past the costly and lengthy process of building an extensive array of cables and radio towers for long-distance service, such as the United States had in place. Instead they could simply set up ground stations with their fixed antennas and lease channels on an Intelsat spacecraft. Then, when domestic demand increased, their governments could purchase complete communications satellites for their own use. Canada was the first to do this, with the first of its Anik spacecraft reaching orbit in 1972. Others followed: Indonesia's Palapa, India's Insat, Australia's Aussat, Mexico's Morelos, and Brazilsat. In addition, 22 Islamic nations formed a regional group, the Arab Space Communication Organization. The first of its spacecraft, called Arabsat, reached orbit in 1985.

Despite competition from domestic and regional satellites, Intelsat continues to grow. The Internet has particularly spurred demand by providing a way to send e-mail overseas at no cost. Accordingly, recent Intelsat spacecraft have weighed up to five tons, which is as heavy as they can get and still reach geosynchronous orbit using existing rockets. Each such spacecraft provides as many as 120,000 telephone circuits, while a specialized satellite, Intelsat K, handles 32 television channels. Moreover, although the French were deeply offended by Paine's rejection of their 1968 request, they have long since reconciled with Intelsat. Their Ariane launch vehicles place many Intelsat spacecraft in orbit.