Saturday, February 6, 2010


Telstar is the name of various communications satellites, including the first ever such satellite able to relay television signals. The first two Telstar satellites were "Telstar 1", launched July 10, 1962 and operational until February 21, 1963, and "Telstar 2", launched May 7, 1963 and operational until May 16, 1965. They were experimental, and nearly identical. Telstar 1 relayed the first television pictures, telephone calls and fax images through space and provided the first live transatlantic television feed.

Belonging to AT&T, the original Telstar was part of a multi-national agreement between AT&T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT (Post, Telegraph & Telecom Office) to develop experimental satellite communications over the Atlantic Ocean. Bell Labs held a contract with NASA, reimbursing the agency three million dollars for each of the two launches, independent of success.

Launched by NASA aboard a Delta rocket from Cape Canaveral on July 10, 1962, Telstar 1 was the first privately sponsored space launch. A medium-altitude satellite, Telstar was placed in an elliptical orbit completed once every 2 hours and 37 minutes, inclined at an angle of approximately 45 degrees to the equator, with perigee about 1000 km from Earth and apogee about 6000 km from Earth (This is in contrast to most of today's communications satellites, which are placed in circular geostationary orbits.

Telstar 1 relayed its first, and non-public, television pictures – of a flag outside Andover Earth Station in Maine, USA – to France on July 11, 1962. Almost two weeks later, on July 23, at 3:00 p.m. EDT, it relayed the first publicly available live transatlantic television signal. The broadcast was made possible in Europe by Eurovision and in North America by NBC, CBS, ABC, and the CBC. The first public broadcast featured CBS's Walter Cronkite and NBC's Chet Huntley in New York, and the BBC's Richard Dimbleby in Brussels. The first pictures were the Statue of Liberty in New York and the Eiffel Tower in Paris. The first broadcast was to have been remarks by President John F. Kennedy, but the signal was acquired before the President was ready, so the lead-in time was filled with a short segment of a televised major league baseball game between the Philadelphia Phillies and the Chicago Cubs at Wrigley Field. The batter Tony Taylor was seen hitting the ball to the right fielder George Altman. From there, the video switched first to Washington, DC; then to Cape Canaveral, Florida; then to Quebec, Canada and finally to Stratford, Ontario. The Washington segment included a press conference with President Kennedy, talking about the price of the American dollar, which was causing concern in Europe.

During that evening, Telstar 1 also relayed the first telephone call to be transmitted through space, and it successfully transmitted faxes, data, and both live and taped television, including the first live transmission of television across an ocean. In August 1963, Telstar 1 became the first satellite used to synchronize time between two continents, bringing the United Kingdom and the United States to within 1 microsecond of each other (previoius efforts were only accurate to 2000 microseconds).

Telstar 1, which had ushered in a new age of the benevolent use of technology, became a victim of technology during the Cold War. The day before Telstar 1 was launched, the United States had tested a high-altitude nuclear bomb (called Starfish Prime) which energized the Earth's Van Allen Belt where Telstar 1 went into orbit. This vast increase in radiation, combined with subsequent high-altitude blasts, including a Soviet test in October, overwhelmed Telstar's fragile transistors; it went out of service in early December 1962, but was restarted by a workaround in early January 1963. The additional radiation associated with its return to full sunlight once again caused a transistor failure, this time irreparably, and Telstar 1 went out of service on February 21, 1963.

According to the US Space Objects Registry, Telstar 1 and 2 were still in orbit as of June 2009.

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