SATELLITE COMMUNICATION

1. Have you look at the sky on a cloudles
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   s clear night?What do you see there high up in the sky?There are millions of stars hiding the secrets of the universe.Among them,if you look at the sky very carefully for sometimes,you can see blinking stars moving from north to south or south to north and you will understand that their movement is very fast.What are they ? Why are they moving so fast?They are man made stars,they are called artificial satellites.
2. An artificial satellite is a spacecraft. It orbits the earth at a fixed distance.Artificial satellite are sent to space on various purposes such as communication, remote sensing military purposes,space astronomy.However,the main purpose of satellites is communication.They bring the world together.It is with the help of communication satellites that we enjoy the thrill of Olympic Games,World Cup Football,Asian Games or the World cup Cricket Finals How does CNN or BBS news come to us?How does the weather forecast come to us? They all are communicated with the help of satellite orbiting the earth.

                 

The first artificial satellite,Sputnik 1 was lunched by Soviet Russia (USSR) on 4th October 1957.It was a competition between the USSR and the United States of America(USA) at the beginning.Later ,other countries like France,China,India and Japan too started lunching their own satellites for various purposes ,mainly for communication.In 1945 the honoured Sri Lanken citizen Arthur C.Clarke made a very famous statement about making communication possuble with countries all over the world with the help of a spacecraft orbiting the earth.The world became a single village as a result of satellite communication.There are commercial communication satellites like TELSTAR,INTELSAT etc.providing communication facilities for the whole WORLD.