This is a list of Solar System objects by greatest aphelion or the greatest distance from the Sun that the orbit could take it if the Sun and object were the only objects in the universe. It is implied that the object is orbiting the Sun in a two-body solution without the influence of the planets, passing stars, or the galaxy. The aphelion can change significantly due to the gravitational influence of planets and other stars. Most of these objects are comets on a calculated path and may not be directly observable. For instance, comet Hale-Bopp was last seen in 2013 at magnitude 24 and continues to fade, making it invisible to all but the most powerful telescopes.