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The use of Satellites in communication and their invention

Answer Text:
The use of Satellites in communication.
- A Satellite is a spacecraft or an artificial device orbiting the earth, moon or another planet, transmitting back to earth scientific information.
- It is launched at a velocity of at least 28,960 km per hour (escape velocity) to enable it overcome
gravitational pull of the earth and thus remain in space.
- In 1680, a British Scientist, Isaac Newton, introduced the idea of artificial satellites.
- The first message to be transmitted by satellite was the Christmas greeting by President Dwight D Eisenhower of the USA in 1958.
- In 1969, the first television pictures were relayed around the earth by satellites from Apollo II astronauts.
- In October 1957, USSR sent sputnik I, the first satellite into the orbit.
- In the same year, the first living passenger, a little dog called Laika, was carried into space by a satellite.
- In 1961, a Russian Yuri Gagarin went into space on board of a satellite.
- In 1981, the US released the first space shuttle which is manned, airplane like craft which orbits the earth.
- In 1983, Challenger, the space shuttle, released a satellite into space.
- In 1986, an accident occurred on the space shuttle, Challenger, killing seven Astronauts.