TheInfoList

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 to 4 km/s. Although a collision is comparatively unlikely, GSO satellites have a limited ability to avoid any debris.[34]

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 to 4 km/s. Although a collision is comparatively unlikely, GSO satellites have a limited ability to avoid any debris.[35]

Debris less than 10 cm in diameter cannot be seen from the Earth, making it difficult to assess their prevalence.[36]

Despite efforts to reduce risk, spacecraft collisions have occurred. The European Space Agency telecom satellite Olympus-1 was struck by a [36]

Despite efforts to reduce risk, spacecraft collisions have occurred. The European Space Agency telecom satellite Olympus-1 was struck by a meteoroid on August 11, 1993 and eventually moved to a graveyard orbit,[37] and in 2006 the Russian Express-AM11 communications satellite was struck by an unknown object and rendered inoperable,[38] although its engineers had enough contact time with the satellite to send it into a graveyard orbit. In 2017 both AMC-9 and Telkom-1 broke apart from an unknown cause.[39][36][40]

A geosynchronous orbit has the following properties:

### Period

All geosynchronous orbits have an orbital period equal to exactly one sidereal day.[41] This means that the satellite will return to the same point above the Earth's surface every (sidereal) day, regardless of other orbital properties.[42][20]:121 This orbital period, T, is directly related to the semi-major axis of the orbit through the formula:

[41] This means that the satellite will return to the same point above the Earth's surface every (sidereal) day, regardless of other orbital properties.[42][20]:121 This orbital period, T, is directly related to the semi-major axis of the orbit through the formula: