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| A communication satellite floating in space |
Satellite: Satellites orbit the Earth from space. It rotates due to Earth's gravitational pull, so no fuel or energy is expended to keep it in space. The earth rotates on its own axis in twenty-four hours, if the satellite can also be rotated around the earth once in twenty-four hours, then the earth will appear to be fixed at a certain place in the sky. Such satellites are called Jio Stationary Satellites. Jio Stationary Satellite cannot be placed at any height. It has to be placed in a fixed orbit of about 36 thousand km. Once a geostationary satellite is placed in the sky, a signal can be sent from one end of the Earth and the satellite can transmit that signal to the other end of the Earth. In this way signals can be sent from one end of the world to another through radio, telephone, mobile phone or internet. When the first geostationary satellite was launched into space in 1964, a new horizon in communication opened up.
There are two problems with communication via satellite Since the satellite is so high above the earth, a very large antenna is needed to send the signal there. The second problem is a bit more complicated. The signal sent from Earth is a radio signal. Wireless signals are fast, but take a while to travel these great distances. So if you talk on the telephone, the other party can't hear you immediately, but you can hear it a little later.
