An Artificial Satellite can be termed as an object which is placed intentionally in orbit. It is estimated that till now, around 6,600 satellites (Mohanta, 2021) have been launched. Out of which, about 4,000 (UCS Satellite Database, 2021) are still operational and the others have completed their life span.
There are mainly two types of artificial satellites based on their direction of motion i.e., the Geostationary Satellites and the Polar Orbiting Satellites (Artificial Satellites, 2021). The Geostationary satellites are those which rotate in orbit as the Earth does.
On the other hand, the Polar Satellites rotate around the north-south orbit and pass over the North and the South Pole (Artificial Satellites, 2021).
Types of Satellites Based on Application
There are multiple types of satellites in orbit on the basis of application.
The Communication Satellites are responsible for passing on signals between a transmitter and a receiver at various sites on the Earth. Such satellites are used for television, internet, telephone, radio transmissions.
The Earth Observation Satellites are used for observing the earth for various purposes. It is commonly used for military purposes for observing the adversary but such satellites are also used for civil purposes. It also helps to monitor the weather conditions and the environmental situations including state of the sea, melting of glaciers, disasters, droughts, and agricultural conditions.
Global Navigation Satellite Systems (GNSS) consist of a network of satellites that provide the information for navigation, positioning, and timing data. GNSS is a group of satellites known as constellations. Global Positioning System (GPS) and GLONASS are examples of Navigation Satellites. GPS was developed by the USA while GLONASS by Russia. GNSS is used in almost every form of transportation, aviation, maritime, etc.
References
(2021). Artificial Satellites. GreeksforGreeks. Retrieved from https://www.geeksforgeeks.org/artificial-satellites/
Mohanta, N. (2021). How many satellites are orbiting the Earth in 2021? Geospatial World. Retrieved from https://www.geospatialworld.net/blogs/how-many-satellites-are-orbiting-the-earth-in-2021/
(2021). UCS Satellite Database. UCS Satellite Database. Retrieved from https://www.ucsusa.org/resources/satellite-database
Pictures credit: https://www.geeksforgeeks.org/artificial-satellites/
