Our solar system consists of the sun, planets, dwarf planets, moons, an asteroid belt, comets, meteors, and other objects. The sun is the center of our solar system; the planets, over 61 moons, the asteroids, comets, meteoroids and other rocks and gas all orbit the Sun. The Planets
The nine planets that orbit the sun are (in order from the Sun): Mercury, Venus, Earth, Mars, Jupiter (the biggest planet in our Solar System), Saturn (with large, orbiting rings), Uranus, Neptune, and Pluto (a dwarf planet). A belt of asteroids (minor planets made of rock and metal) orbits between Mars and Jupiter. These objects all orbit the sun in roughly circular orbits that lie in the same plane, the ecliptic (Pluto is an exception; it has an elliptical orbit tilted over 17° from the ecliptic).
The inner planets (those planets that orbit close to the Sun) are quite different from the outer planets (those planets that orbit far from the Sun).
- The inner planets are: Mercury, Venus, Earth, and Mars. They are relatively small, composed mostly of rock, and have few or no moons.
- The outer planets include: Jupiter, Saturn, Uranus, Neptune, and Pluto. They are mostly huge, mostly gaseous, ringed, and have many moons (again, the exception is Pluto which is small, rocky, has one moon, and is considered to be a dwarf planet).
Small Bodies
There are other smaller object that orbit the Sun, including asteroids, comets, meteoroids and dwarf planets.
- Asteroids (also called minor planets) are rocky or metallic objects, most of which orbit the Sun in the asteroid belt between Mars and Jupiter.
- Comets are small, icy bodies that orbit the sun. They have very long tails.
- Meteoroids are small bodies that travel through space. They are stony and/or metallic and are smaller than asteroids. Most are very tiny.
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