Solar System planets and orbits. Illustration of Earth's solar system, showing the eight planets that orbit the Sun, plus the dwarf planet Pluto (which was previously a planet). The separations of the orbits are not shown to scale. Most of the mass of the solar system is found in the Sun. The eight planets, from inner to outer, are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The orbit of Pluto (within the Kuiper Belt) is tilted compared to the those of the planets. The inner four planets are rocky, the outer four are gas giants. Also shown is the asteroid belt between the orbits of Mars and Jupiter, and the rings of Saturn and Uranus.