Tuesday, July 10, 2012

50 Years Ago: TELSTAR-1 and the New Age of Communications

NASA art of TELSTAR-1 in space.

Today marks the 50th anniversary of a great leap forward in world communications, the launch of TELSTAR-1 from Cape Canaveral on July 10, 1962. TELSTAR-1 was not the first communications satellite; that was ECHO-1A sent up on May 13, 1960. But ECHO was a reflective-passive device; signals were bounced, or reflected, off the spherical surface and received on Earth beyond the horizon. TELSTAR broke new ground. To begin with, TELSTAR was the first privately sponsored space launch effort. The satellite was built at Bell Telephone Laboratories, and included transponders which relayed television or telephone channels back to the ground, another first. Third, the launch was the 10th successful blast-off of the Thor-Delta rocket system. Other Thor-Delta launches had included ECHO-1, TIROS weather satellites, EXPLORERs 10 and 12, ARIEL-1, and OSO-1.

A TELSTAR satellite under construction.

Weighing about 170 pounds, TELSTAR was powered by small solar panels which generated about 14 watts of energy. It would eventually transmit the first public television and telephone signals (including the first Fax!) and would also transmit the first transAtlantic television signal.

Thor-Delta rocket.

TELSTAR-1 was sent into space from Launch Complex 17, pad B, on a Thor-Delta rocket. Its orbit was elliptical, or egg-shaped, and the satellite circled the Earth every 2 hours and 37 minutes. It continued in operation until February the next year, but TELSTAR-1 still orbits the Earth to this day. The end of TELSTAR-1 was premature, because it was exposed to higher amounts of radiation than it normally would have encountered from the Van Allen radiation belt. The day before its launch, the US Air Force had launched a nuclear weapon into space to test the effects of the blast on potential enemy rockets. Further space nuclear tests, including a Soviet explosion in October 1962, eventually degraded the electronics.

To realize the significance of this launch, you only have to think of how many times each day you call someone cross-country, watch television on your satellite channels, or receive the Internet on your computer. Yes, a lot of towers and cables are involved locally, but the transmission of channels and frequencies to those localities is done through satellite communications. Also consider how much of our nation's defense depends upon secure transmission of coded signals to our troops and installations around the world. And it all started 50 Years Ago. We live in a world our ancestors barely dreamed about.

UPDATE: NASA History Office noted the anniversary today on its Twitter account (@NASAhistory) and provided this link to a wonderful short news film from the day which shows TELSTAR's construction, launch,and the first images transmitted. Wonderful little film, thanks, NASA!

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