Downloaded from NASA Spacelink!
In 1945 British scientist and science fiction writer, Arthur
C. Clarke, published a technical paper in which he suggested that
communications satellites were feasible. Fifteen years later, NASA
launched its first communications satellite, Echo, a silvery balloon
that orbited Earth every 114 minutes.
Echo was a passive satellite that reflected radio signals
back to Earth. Two years later, Relay, the first active satellite was
launched to receive signals, amplify them, and transmit them back to
Earth.
The Echos were inflated in space to spherical balloons of
aluminized Mylar, 100 and 135 feet in diameter, respectively. Passive
communications satellites, they reflected radio signals between ground
stations. They also provided information about the density of the
upper atmosphere. Echo 1 was launched August 12, 1960, and Echo 2 in
January 1964.
Relay 1 was NASA's first active repeater experimental
satellite; launched December 13, 1962, it handled 12 simultaneous
two-way telephone conversations or one television channel and provided
the first satellite communications link between North and South
America and Europe. Relay 2, an improved version, was launched in
January 1964.
The Syncoms were three experimental, active satellites. The
name, coined from the first syllables of "synchronous communications,"
referred to their orbits. Each Syncom satellite weighed about 85
pounds. Syncom I was launched February 14, 1963, but did not reach
synchronous orbit and communications failed. Syncom II, launched July
26, 1963, was the first satellite placed in synchronous orbit. It was
active in many successful intercontinental communication experiments.
Syncom III, launched August 19, 1964, was the first stationary Earth
satellite. It demonstrated the practicality and effectiveness of
stationary, active communication satellites. In orbit near the
International Date Line, it was used to telecast the 1964 Olympic
Games in Tokyo to the United States, the first television program to
cross the Pacific.