Solar system. Artwork of the eight planets orbiting the Sun (upper centre), as seen from the orbit of Saturn (lower left). The orbits of the planets are shown as blue lines. Distances and sizes are not to scale. In their order from the Sun, the planets are: Mercury, Venus, Earth, Mars (the small, rocky inner planets), Jupiter (centre right), Saturn, Uranus and Neptune (the outer gas giant planets). Uranus and Neptune are at upper left. As of August 2006, Pluto (not shown) is a Dwarf planet. The asteroid belt (between Mars and Jupiter) is also seen, and the Milky Way galaxy is in the background.