Satellites that are launched in to the orbit by using the rockets are called man-made satellites or artificial satellites. Artificial satellites revolve around the earth because of the gravitational force of attraction between the earth and satellites. Unlike the natural satellites (moon), artificial satellites are used in various applications. The various applications of artificial satellites include:
1. Weather forecasting
2. Navigation
3. Astronomy
4. Satellite phone
5. Satellite television
6. Military satellite
7. Satellite internet
8. Satellite radio.
1. Weather forecasting
Weather forecasting is the prediction of the future of weather. The satellites that are used to predict the future of weather are called weather satellites. Weather satellites continuously monitor the climate and weather conditions of earth. They use sensors called radiometers for measuring the heat energy released from the earth surface. Weather satellites also predict the most dangerous storms such as hurricanes.
2. Navigation
Generally, navigation refers to determining the geographical location of an object. The satellites that are used to determine the geographic location of aircrafts, ships, cars, trains, or any other object are called navigation satellites. GPS (Global Positioning System) is an example of navigation system. It allows the user to determine their exact location at anywhere in the world.
3. Astronomy
Astronomy is the study of celestial objects such as stars, planets, galaxies, natural satellites, comets, etc. The satellites that are used to study or observe the distant stars, galaxies, planets, etc. are called astronomical satellites. They are mainly used to find the new stars, planets, and galaxies. Hubble space telescope is an example of astronomical satellite. It captures the high-resolution images of the distant stars, galaxies, planets etc.
4. Satellite phone
Satellite phone is a type of mobile phone that uses satellites instead of cell towers for transmitting the signal or information over long distances.
Mobile phones that use cell towers will work only within the coverage area of a cell tower. If we go beyond the coverage area of a cell tower or if we reach the remote areas, it becomes difficult to make a voice call or send text messages with the mobile phones. Unlike the mobile mobiles, satellite phones have global coverage. Satellites phones uses geostationary satellites and low earth orbit (LEO) satellites for transmitting the information.
When a person makes a call from the satellite phone, the signal is sent to the satellite. The satellite will receives that signal, processes it, and redirects the signal back to the earth via a gateway. The gateway then send the signal or call to the destination by using the regular cellular and landline networks. The usage of satellite phones is illegal in some countries like Cuba, North Korea, Burma, India, and Russia.
5. Satellite television
Satellite television or satellite TV is a wireless system that uses communication satellites to deliver the television programs or television signals to the users or viewers.
TV or television mostly uses geostationary satellites because they look stationary from the earth. Hence, the signal is easily transmitted. When the television signal is send to the satellite, it receives the signal, amplifies it, and retransmit it back to the earth. The first satellite television signal was send from Europe to North America by using the Telstar satellite.
6. Military satellite
Military satellite is an artificial satellite used by the army for various purposes such as spying on enemy countries, military communication, and navigation.
Military satellites obtain the secret information from the enemy countries. These satellites also detect the missiles launched by the other countries in the space.
Military satellites are used by armed forces to communicate with each other. These satellites also used to determine the exact location of an object.
7. Satellite internet
Satellite internet is a wireless system that uses satellites to deliver the internet signals to users. High-speed internet is the main advantage of satellite internet. Satellite internet does not use cable systems, but instead it uses satellites to transmit the information or signal.
8. Satellite radio
Satellite radio is a wireless transmission service that uses orbiting satellites to deliver the information or radio signals to the consumers. It is primarily used in the cars. When the ground station transmit signal to the satellite that is revolving around the earth, the satellite receives the signal, amplifies it, and redirects the signal back to the earth (radio receivers in the cars).