Mean motion

From Wikipedia, the free encyclopedia

Mean Motion, n\,\!, is a measure of how fast a satellite progresses around its orbit. Unless the orbit is circular, the Mean Motion is only an average value, and does not represent the instantaneous angular rate.

In databases of satellite orbital parameters the Mean Motion is typically specified in revolutions per day.

[edit] Calculation

n =  \sqrt{\frac{GM}{a^3}}\,\!

will return units of radians/second.

where:

(note that G\,\! and M\,\! are typically combined to give the Standard gravitational parameter, \mu\,\!)