Editing Geostationary orbit (section)

===Period===
The orbital period is equal to exactly one sidereal day. This means that the satellite will return to the same point above the Earth's surface every (sidereal) day, regardless of other orbital properties. For a geostationary orbit in particular, it ensures that it holds the same longitude over time.<ref name="smad"/>{{rp|121}} This orbital period, ''T'', is directly related to the semi-major axis of the orbit through [[Kepler's laws|Kepler's Third Law]]:

: <math>T = 2\pi\sqrt{a^3 \over \mu}</math>

where:
* {{mvar|a}} is the length of the orbit's semi-major axis
* {{mvar|μ}} is the [[standard gravitational parameter]] of the central body<ref name="smad"/>{{rp|137}}