In Terms of Media: Satellites
This article originally appeared in Issue# 3
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Transmitters in the Sky
This past October marked the twentieth anniversary of Sputnik, the tiny Russian satellite that launched the whole world into the space age. Since that time over 10,000 satellites and space probes have been rocketed from earth, many of which continue to circle the globe providing meteorological information, scientific observations and a growing opportunity to communicate instantaneously with almost every part of the world.
A communication satellite can be defined as a space platform on which are mounted a complex of earth-oriented antennas which serve as "transmitters in the sky." At 22.500 miles above the earth, it takes only three satellites above the equator to relay signals around the entire curved surface of the earth. At that height satellites are said to be in geostationary orbit, i.e. they revolve at a rate that always keeps them above the same spot on earth. Thus 'fixed," they are perfect links in a worldwide communications system.
Remember "Early Bird?" That was one of the first international communications satellites. It could relay up to 240 telephone calls in both directions simultaneously. Now, 12 years later, RCA's SATCOM II is made up of 24 transponders, each able to handle 3000 telephone conversations! In the future, technicians on board the space shuttle will be able to build, in space, giant satellites that will allow for fantastic new developments in the exchange and sharing of information by humankind.
Generally the smaller the satellite in the sky, the larger the earth station needed to transmit or receive the signal. (In satellite jargon, the signal transmitted from earth is the uplink; the signal transmitted from the satellite is the downlink. Similarly the larger and lore powerful the satellite in space, the smaller the dish needed on earth to receive the signal. In contrast to the 100 foot, 350-ton dishes needed for the small satellites today, technicians are envisioning portable two-or-three-foot earth stations that could enable every home, school or office to receive direct television signals from homes, schools or offices across the country... or around the world. The day of the Dick Tracy two-way radio wristwatch would soon follow!
But what else can satellites do NOW besides provide 'live via satellite TV coverage of news, sports or disasters? Well, satellites are marvelous ways to close the distance-gap between rural parts of the world that do not even have land links (cables or ground transmitters) to the rest of the world. In the U.S., the Application Technology Satellites have been used to link up paramedics in remote Eskimo villages with medical specialists at the University of Alaska and to provide in-service teacher training courses for reaching teachers throughout Appalachia. More than just televising lectures one-way the satellite program provides the capability for live interaction seminars between participants at several sites. Such satellite teleconferences may soon be cheaper than the cost of transportation now necessary for bringing conferees together. For other uses, computers can be linked through satellites to provide instant exchange of information by libraries, research organizations or businesses.
While business has begun to utilize satellites to cut costs (and increase profit) there is a growing interest by religious and human service groups. The National Women's Agenda has recently proposed a national feminist news service, long-distance document transmission, and a Washington "hotline" on legislation affecting women, all, of course, possible by satellite. And the National Council of Churches has suggested that religious uses of satellites might include continuing education programs for clergy, a national data bank of church records (baptisms, marriages), interconnection of seminary libraries or international disaster relief coordination.