Retrograde Orbit
A retrograde orbit is an orbit where the satellite travels in an East to West direction instead of the common West to East orbit. The normal West to East orbits are known as prograde orbits.
Retrograde orbits are uncommon due to the much higher velocities necessary for successful launch and the associated higher costs. During a prograde launch, rotational velocity of the Earth is added to the velocity of the launch rocket. In a retrograde launch, the rotational velocity of the Earth is subtracted from the velocity of the launch rocket.
Satellites designed to observe the Earth are sometimes launched in sun-synchronous retrograde orbits in order to maintain a constant angle of surface illumination.
Space War
Satellites in retrograde orbits could theoretically be used as ballistic weapons to smash into satellites in prograde orbits.
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- Polar Orbit
A polar orbit is an orbit of any object in space, natural or synthetic, that passes around the Earth in a North-to-South direction rather than a West to East direction, which is known as an “equatorial orbit”. Polar orbits are advantageous because they will eventually travel across every possible latitudinal and longitudinal position on the [...]...
- Low Earth Orbit
Low Earth Orbit (LEO) refers to a satellite which orbits the earth at altitudes between (very roughly) 200 miles and 930 miles. Low Earth Orbit satellites must travel very quickly to resist the pull of gravity — approximately 17,000 miles per hour. Because of this, Lowe Earth Orbit satellies can orbit the planet in as [...]...
- Medium Earth Orbit
Medium Earth Orbit (MEO) refers to a satellite which orbits the earth at an altitude below 22,300 miles (geostationary orbit) and above the altitude of Low Earth Orbit (LEO) satellites. Medium Earth Orbit represents a series of tradeoffs between geostationary orbit (GEO) and Low Earth Orbit (LEO). Medium Earth Orbit enables a satellite provider to [...]...
- Inclination
Inclination is the angle between a satellite orbit and the equator. Inclination is measured as the angle at which the satellite crosses the equator while passing from the southern hemisphere to the northern hemisphere. A satellite travelling in a geostationary obit will have an inclination of zero. Inclination is between 0 and 90 degrees for [...]...
- Satellite Phone
A satellite phone is a mobile telephone which communicates using satellites instead of using cell towers. Three major satellite phone networks are currently in operation: Iridium Globalstar Thuraya Iridium The Iridium network uses 66 low earth orbit satellites in polar orbits 485 miles above sea level. The use of low earth orbit satellites helps minimize [...]...