Solar system planets. Artwork of the nine planets of the solar system arrayed from bottom to top in order of their distance from the Sun. The size of each planet is to scale. The four small, rocky planets of the inner solar system are Mercury, Venus, Earth and Mars. The four large, gas giant planets of the outer solar system are Jupiter, Saturn, Uranus and Neptune. Finally, Pluto is a Dwarf planet of rock and ice. Planetary rings and moons, and the asteroid belt (between Mars and Jupiter) are all shown. Uranus is unique in that it rotates tipped on its side.