What parts of the Solar System are described?

1. These small, rocky fragments can be found in the Kuiper Belt, beyond Neptune.

2. It is made up of hydrogen and helium. Its surface temperature is about 6,000 degrees Celsius.

3. Comets come from here. It surrounds the Solar System.

4. Many asteroids are found in this part, that lies between Mars and Jupiter.

5. This group consists of Mercury, Venus, the Earth and Mars. They orbit close to the Sun.

6. This group consists of Jupiter, Saturn, Uranus and Neptune; they are found beyond the asteroid belt.

7. Some of these are very small, for example, Pluto.

The Solar System consists of a single star, the Sun, the planets and a huge number of smaller objects: moons, comets, asteroids, dwarf planets.

The inner Solar System extends from the Sun to Neptune.

The outer Solar System lies beyond Neptune.

Geocentric model: the Earth was the centre of the universe and the Sun, Moon and planets orbited the Earth.

Heliocentric model: the Sun was at the centre of the universe.