SATELLITE HISTORY
Arthur C. Clark wrote the first well-known article on
communication satellites. “Extra-Terrestrial Relays” was published in Wireless
World in 1945. In the article, Clark discussed geosynchronous earth orbit and
the possibility of covering the earth with three satellites.
The actual journey into space began on October 4, 1957, when
the Soviet Union launched Sputnik 1, the world’s first orbital space craft,
which orbited the world for three months. A month later the Soviets launched sputnik
2 and its passenger Laika, a dog who has the distinction of being the first
known living creature to escape earth and enter outer space. The space race was
on, and in February of 1958, the United States launched Explorer 1.
The first communication satellite was launched on December
18, 1958. Signal communication by Orbital Relay (SCORE), which broadcasted a
Christmas message from President Eisenhower – “Peace on Earth, Good will toward
men” – orbited the earth for 12 days until the battery failed. The main purpose
of SCORE project was to prove that an atlas missile could be put into orbit.
Combined, the U.S. and U.S.S.R. launched six satellites in
1958, 14 satellites in 1959, 19 in 1960 and 35 in 1961. In 1962, the United
Kingdom and Canada launched satellites of their own, along with the 70
satellites launched by the U.S. and U.S.S.R.
On August 12, 1960, the United States launched Echo 1, a
passive reflector satellite with no amplification possibilities. Echo 1 could
only reflect the radiation back to the earth. At the time of its launch, it was
thought that passive reflector satellites could serve a purpose in
communications, but the technology was soon abandoned.
Bell Telephone Laboratories assisted in the Echo 1 project.
Knowledge gained working on Echo 1 helped Bell to develop Telstar, an
experimental satellite that relayed television signals. Telstar was launched
into medium earth orbit in 1962. In the six months following the launch,
stations in the United States, Britain and France conducted about 400
transmissions with multichannel telephone, telegraph, facsimile and television
signals, and they performed over 250 technical tests and measurements.
Near complete earth coverage (excluding polar areas) was
achieved with the development of Intelsat and the launching of satellites into
geosynchronous earth orbit over the Atlantic (1965), Pacific (1967), and the
Indian oceans (1969). A combination of more than 130 governments and
international organisation control Intelsat. Intelsat, along with Inmarsat,
which is used in international shipping, is open to use by all nations. The
Intelsat consortium owns the satellites, but each nation owns their own earth
stations. In 1997 Intelsat had 19 satellites in geostationary orbit.
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