is that of the launch site's latitude, so launching the satellite from close to the equator limits the amount of inclination change needed later. Additionally, launching from close to the equator allows the speed of the Earth's rotation to give the satellite a boost. A launch site should have water or deserts to the east, so any failed rockets do not fall on a populated area. Most launch vehicles place geosynchronous satellites directly into a geosynchronous transfer orbit (GTO), an elliptical orbit with an apogee at GSO height and a low perigee. On-board satellite propulsion is then used to raise the perigee, circularise and reach GSO. Once in a viable geostationary orbit, spacecraft can change their longitudinal position by adjusting their semi-major axis such that the new period is shorter or longer than a sidereal day, in order to effect an apparent "drift" Eastward or Westward, respectively. Once at the desired longitude, the spacecraft's period is restored to geosynchronous. Proposed orbits Statite proposal A statite is a hypothetical satellite that uses radiation pressure from the sun against a solar sail to modify its orbit. It would hold its location over the dark side of the Earth at a latitude of approximately 30 degrees. It would return to the same spot in the sky every 24 hours from an Earth-based viewer's perspective, so be functionally similar to a geosynchronous orbit. Space elevator A further form of geosynchronous orbit is the theoretical space elevator. When one end is attached to the ground, for altitudes below the geostationary belt the elevator maintains a shorter orbital period than by gravity alone. Retired satellites Geosynchronous satellites require some station keeping to keep their position, and once they run out of thruster fuel and are no longer useful they are moved into a higher graveyard orbit. It is not feasible to deorbit geosynchronous satellites as it would take far more fuel than slightly elevating the orbit, and atmospheric drag is negligible, giving GSOs lifetimes of thousands of years. The retirement process is becoming increasingly regulated and satellites must have a 90% chance of moving over 200 km above the geostationary belt at end of life. Space debris Space debris in geosynchronous orbits typically has a lower collision speed than at LEO since most GSO satellites orbit in the same plane, altitude and speed; however, the presence of satellites in eccentric orbits allows for collisions at up