A natural or artificial object orbiting the larger object is named as a satellite.
As Moon is Earth's satellite, while it orbits the Earth. Same Earth is a satellite of Sun. On the other hand, man-made satellites are sent into space to perform some particular functions, for instance, Earth Observation, communication, weather forecasting, navigation, and much more. Sputnik1 was the first satellite launched on 4 October 1957 by the USSR and since then, about 8,900 have been launched. Satellites are semi-independent computer-controlled systems.
Satellites can be distinguished by its weight (maximum weight)
- Cubesat (max. 1.32 Kg)
- Small satellite (smallsat) (max. 1,200 Kg)
- Mini satellite (max. 600 Kg)
- Micro satellite (max. 200 Kg)
- Nano satellite (Nanosatellite) (max. 10 Kg)
- Pico satellite (max. 1 Kg)
- Femto satellite (max. 100 g)
or by its application