# Kepler's equation

Kepler's equation is one of the important formulae that enables the position of a body in an
elliptical orbit to calculated at any given time from its orbital elements.
It relates the mean anomaly, *M*, of
the body to its eccentric anomaly, *E*, by the following:

*M* = *E* - *e* sin *E*

where *e* is the eccentricity of the
orbit.