The Solar System is made up of the Sun, the planets, their moons, asteroids and comets.
WHAT TO SEE
The Sun is a star that lives at the centre of the Solar System. Its huge gravity holds the planets in place.
The planets all revolve around the Sun. There are eight in total - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Moons rotate around their parent planet. Earth has one moon, but some planets have over 50. Only Mercury and Venus do not have any moons.
Asteroids are rocky bits of runs up to 1,000km (620 miles) across. Most live in the asteroid belt between Mars and Jupiter. They are the remnants from early planets that collided and were torn apart.
Comets are dirty snowballs of ice and dust that revolve around the Sun in long orbits. When they approach the Sun they heat up, leaving a trail of gas behind them, which looks like a tail.
Recent comets to fly-by the Sun include Halley, Hale-Bopp and Ikeya-Zhang.
- The Rocky or Terrestial planets
The four planets closest to the Sun are:
These are called the 'rocky' or 'terrestrial' planets. They are small by planetary standards and made of similar materials to the Earth.
They are known as the 'gas giants'. They all have rings and lots of moons. The gas giants are made up mostly of hydrogen, helium, frozen water, ammonia, methane, and carbon monoxide.
The Dwarf Planets
The International Astronomical Union redefined the term planet in August 2006, so Pluto is now classified as a dwarf planet. There are two other dwarf planets in the solar system, Ceres and Eris.