Outline of the Solar System
Solar System – gravitationally bound system comprising the Sun and the objects that orbit it, either directly or indirectly. Of those objects that orbit the Sun directly, the largest eight are the planets (including Earth), with the remainder being significantly smaller objects, such as dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly, the moons, two are larger than the smallest planet, Mercury.
Primary (astronomy)
The center of mass is the average position of all the objects weighed by mass. The Sun is so massive that the Solar System's barycenter lies very near the Sun's center. However, the gas giants are far enough from the Sun that the Solar System's barycenter can be outside the Sun, despite the Sun comprising most of the Solar System's mass.