Definition that contains solar system
- sun the star that is the source of light and heat for the planets in the solar system
- planet (astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction
- au a unit of length used for distances within the solar system; equal to the mean distance between the Earth and the Sun (approximately 93 million miles or 150 million kilometers)
- apex the point on the celestial sphere toward which the sun and solar system appear to be moving relative to the fixed stars
- planetarium an apparatus or model for representing the solar systems
- copernicus Polish astronomer who produced a workable model of the solar system with the sun in the center (1473-1543)
- kbo any of many minor planets in the Kuiper belt outside the orbit of Neptune at the edge of the solar system
- kuiper United States astronomer (born in the Netherlands) who studied the solar system and suggested in 1951 that there is a belt of comet-like debris at the edge of the solar system (1905-1973)
- laplace French mathematician and astronomer who formulated the nebular hypothesis concerning the origins of the solar system and who developed the theory of probability (1749-1827)
- planetesimal one of many small solid celestial bodies thought to have existed at an early stage in the development of the solar system