Geostationary Orbit Distance

A satellite is an object that orbits or goes around the larger objects such as planets. The natural satellite for earth is the moon. With advancement in science and technology, man has been able to send hundreds of man-made satellites into orbit. These satellites have been able to increase the communication, send radio signals, television signals, provide us with detailed and advanced weather reports, etc. There are two ways in which man-made satellites circle around the earth that include polar orbit and geostationary orbits.

What is a Polar Orbit?

A satellite in a polar orbit is the one that travels around the North and South Poles. These polar satellites are sent several hundred miles to several thousand miles above the surface of the earth. These satellites tend to circle around the earth about 14 times a day.

What is Geostationary Satellite

The geostationary satellites are those satellites that are always positioned over the same spot on earth. These satellites orbits the earth at the same speed as the earths rotation at the same latitude. This latitude is specifically 0º latitude, that is, equator. Therefore, many times these geostationary satellites appear to be hovering in the same spot in the sky and over the same patch of ground all the times. In this article, we shall concentrate on geostationary orbits. Let us go into the details of geostationary orbits.

What is Geostationary Orbit

The geostationary orbits are also called geosynchronous or synchronous orbits. The geostationary orbits have the same orbital period as that of the earth. If the geosynchronous orbit is circular and equatorial then it will maintain the same position over earth. A circular geostationary orbit distance from earth is about 42,164 km from the center of the Earth or approximately 35, 790 km above mean sea level.

What Determines Geostationary Orbit

By using gravitational force equations and knowing the mass of earth and satellite, the geostationary orbit can be determined. You can do this by equating the centripetal force which holds the satellite in orbit with the gravitational force. By putting in the extra constraint of the angular speed of the satellite in orbit should match with that of earths rotational speed, the geostationary orbit distance is calculated. You will find the derivation at many resources over the Internet. The final formula that helps to determine geostationary orbit is:

r = (µ / ɷ ²) ^⅓

Who Developed the Concept of Geostationary Orbit

The person who is credited for developing the geostationary orbit concept was a well-known science fiction author, Arthur C. Clarke. Many had pointed out that bodies that travel to a certain distance above earth on the equatorial plant remain motionless with respect to earth's surface. However, the suggestion of permanent man-made satellites was given by Clarke in an article that was published in 1945' Wireless World.

The first geosynchronous satellite was sent into orbit in 1963 and in the following year the first geostationary satellites was sent. The only geostationary orbit distance is in the plane with the equator, thus, these satellites can be sent in only one circle around the world. Thus, the grounds of geostationary satellites is very limited. The number of geostationary satellites is very high, although they won't be bumping one another. But a lot of precaution has to be taken so that their frequencies do not interfere with their nearest neighboring satellites.

Uses of Geostationary Orbits

There are plenty of useful geostationary orbit applications that includes:

• Meteorology: They help in real time operational surveys of the cloud systems, troposphere, sea temperature, land surface temperature, etc.
• Telecommunication: The world wide telecommunication system of telephones, television, digital transmission, etc. all get their signals through geostationary satellites in orbit.
• Armed Forces: The armed forces around the world use geostationary orbits for detection of rocket launches, keep track of alarm systems, and many other defense moves.

This was in short about the geostationary orbits distance information. The geostationary orbit distance from earth should be 35, 786 km from the surface. If the distance is any closer to earth, the orbit will decay. If it is farther away, the satellite will escape the earth's gravitational pull.

Acknowledgment: I am thankful to Buzzle author Mr. Gray Pilgrim for his immense support and help in structuring this article on geostationary orbit distance.