Our solar system consists of the sun, nine known planets and their moons, comets, asteroids, meteoroids, and stars.  The planets are divided into two main groups:  the inner planets and the outer planets.  The inner planets are the first four from the sun:  Mercury, Venus, Earth, and Mars.  The last five make up the outer planets:  Jupiter, Saturn, Uranus, Neptune, and Pluto.  All the planets orbit the sun.