heliocentric orbit

Motion of the Solar System's barycenter relative to the Sun

A heliocentric orbit (also called circumsolar orbit) is an orbit around the Sun. The inner planets are mainly influenced by the Sun's gravity, and orbit points close to the center of the Sun ('heliocentric' in a strict sense). The outer planets, and other more distant objects, tend to orbit points close to the barycenter of the Solar System, which is usually located within or very near the surface of the Sun. Comets which traverse the inner Solar System shift between a nearly heliocentric focus, when they are close to the Sun, and a nearly barycentric one when they are more distant than Jupiter. All planets, comets, and asteroids in the Solar System, and the Sun itself are in such orbits, as are many artificial probes and pieces of debris. The moons of planets in the Solar System, by contrast, are not in heliocentric orbits, as they orbit their respective planet (although the Moon has a convex orbit around the Sun).