What are the planets in the solar sytem?

There are 8 planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. These planet started to form 4.6 billion years ago. The material closest to the Sun made the four rocky rocky worlds, Mercury, Venus, Earth and Mars. Further away in the outer disc where it is much colder, rocky bodies formed and then pulled large amounts of gas toward them. These were the large gas planets, Jupiter, Saturn, Uranus and Neptune.

Pluto, which is made of different material, was originally classified as a planet. However, it is now recognised as the largest member of a distinct region called the Kuiper belt.