Planeedi elliptilise orbiidi elemendid on tõususõlm, veerupunkt, kevadpunkt, orbiidi kese ning orbiidi tasandi ja ekliptika tasandi vaheline kaldenurk.
Numerical eccentricity of the orbit is the eccentricity of the orbital ellipse. Eccentricity is a measure of how an orbit deviates from circular. A perfectly circular orbit has an eccentricity of zero; higher numbers indicate more elliptical orbits.
