An electronic device that is sent into space and move around the earth or another planet is called an artificial satellite. A man made satellite revolves around the orbit of a planet like a natural satellite. The size of an artificial satellite is comparatively smaller than that of a natural satellite. Artificial satellite are mainly used for communicating by radio, television, internet , etc. Satellite are used for scientific study and research, navigational purposes, military surveillance and making weather predictions.
The artificila satellite is an important invention of the past century. Most of the research relating to astronomy, weather, and earth is being carried out by satellites. The satellite has brought about a communcation revolution. We are able to see live events in any part of the world by satellite. Pakistan is among those countries which have sent many satellite to space for communication, weather forecasts and research purposes.
Satellite signals are sent to space by radar from a specified place known as the Ground satation. When these signals arrive at a satellite, they are known as Up link. The satellite operates according to the instructions from the signals and sends the collected data in the form of signals to another Ground Station on Earth. The signals received from a satellite are called Downlink.
A satellite can move around earth at an altitude of 8000 km to 36000. A satellite move constantly due to the gravity of earth. A satellite is launched into an easterly direction because the earth moves from east to west, causing an increase in the speed of the satellite.
CubeSat is very small satellite weighing only one and a hakf kilogrammes. The mai objective of this satellite is to collect scientific data on the enviroment and space.
Suoarco has palns to send a modern satellite into sapce. This satellite will help to conduct research on sapce and the earth.