Telstar: the satellite that helped turn the globe into a village
WORDS that mark a turning point in history are often rather mundane. So it was with the telephone call that Frank Kappel, chairman of AT&T, sitting in Andover, Maine, put through to Vice-President Lyndon B. Johnson in Washington, D.C., at 7:36 p.m. (EDT) July 10, 1962. ``How do you hear me?'' Kappel asked. ``You're coming through nicely,'' the vice-president said. Shakespeare might have put it more dramatically. But that banal chitchat electrified the world. Telstar - the first true communications satellite - had transmitted the first telephone call in history to be relayed through space.
That sapphire-studded satellite, about as big as a beach ball (34.5 inches in diameter) commanded global attention. Although this first experimental system was mainly a transatlantic link, people on all continents recognized it as a symbol of a communications breakthrough that would link the world more tightly than ever before. It wasn't long before we were talking about the ``global village.''
The first full-scale TV test was to have come a week after launching. But so exuberant were the American, British, and French experimenters that - with some grumbling about protocol from British officials - they went ``live'' with an impromptu exchange of programs on July 11. The Americans featured their national anthem and more remarks from Kappel. The British showed their receiving station at Goonhilly Downs. The French sent a cabaret with songs by Yves Montand and Michele Arnaud.
We take satellite communications for granted now. But Telstar's instant success was a tremendous engineering breakthrough. It would have been impossible without key inventions made over the preceding decade - mainly by Bell Laboratories. These included the sensitive maser receiver that detected signals from the satellite that were as weak as a trillionth of a watt.
Actually, the first communications satellite was the moon. US Army engineers bounced experimental signals off it in 1951 and relayed some messages this way when a massive solar storm interrupted communications in 1955. NASA made more elaborate signal bounce tests in the early 1960s with the Echo 1 and 2 balloon satellites.
But a practical system was needed to capture, amplify, and rebroadcast signals. That depended critically on the sending and receiving stations. So much of Telstar's success lay in pioneering work done on the ground to match well-tested techniques and equipment with untried space technology. Not the least of these challenges was tracking Telstar itself.
The satellite traveled in an orbit inclined 45 degrees to the equator at heights that varied from about 600 miles to 3,500 miles altitude, at speeds between 11,000 and 16,000 miles an hour. It was at its highest over the Atlantic region, where it provided intercontinental linkages for about 18 minutes. Making contact with it was like trying to hit a speeding basketball several thousand miles away with a rifle bullet.
To do this, AT&T installed a gigantic horn antenna - 177 feet long weighing 340 tons - at the world's first satellite earth station in Andover, Maine. Looking into that great horn was like peering into the throat of a whale. Yet, though it appeared ungainly, it moved with a precision that tracked Telstar to an accuracy of less than 1/50th of a degree. That's quite a contrast to the backyard dishes that now point more or less in the direction of a satellite to pick up TV programs.
The Telstar experiment pioneered important technology. But an operational system would need several dozen satellites. Commercial operators adopted the better strategy of placing a few satellites in the so-called geosynchronous orbit 22,300 miles above the equator, as science-fiction writer Arthur C. Clarke had prophetically suggested in 1945. Here, satellites remain over a given ground area and are easy to track.
Telstar, which still orbits Earth, failed in 1963. Radiation had damaged its sapphire-covered solar cells and perhaps other components. The vision it raised of a global village is now a reality. Humanity has yet to adjust to this new intimacy, which can instantly make the joys and woes of one nation a global concern.
The Christian Science Monitor saluted Telstar with an editorial that foresaw this challenge, saying: ``The creative thinking that is dissolving limitations demonstrates what men can accomplish as talented, often dedicated, individuals. The political and social questions to which their achievements give rise are a challenge to all men to demonstrate the mature judgment that will control their use to benefit mankind.''
A Tuesday column. Robert C. Cowen is the Monitor's natural science editor.
Last week's ``Research Notebook'' misnamed the former head of AT&T, Frederick Kappel. The Monitor regrets the error.