heliocentric coordinate system
heliocentric coordinate system(hee-lee-oh-sen -trik) A coordinate system referring usually to the plane of the ecliptic but specifying position with respect to the center of the Sun rather than that of Earth (see geocentric coordinate system). The coordinates – heliocentric latitude and longitude – are used to determine the relative positions of objects in the Solar System. See also barycenter.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006