Nota Penting

The Solar System

The constituents of the Solar System

1 The Solar System consists of:

        (a) the Sun

        (b) planets

        (c) natural satellites

        (d) asteroids

        (e) meteors

        (f) comets

2     (a) The Sun is the centre of the Solar System.

       (b) It is a star because it gives out light and heat. It is the only star in the Solar     

        System.

       (c) The Sun is the biggest body in the Solar System. It consists of a ball of hot 

       gases.

Planets of the Solar System

1 Planets are bodies in the Solar System that move round the Sun.

       (a) A planet does not give out its own light and heat.

       (b) We can see other planets from Earth because they reflect light from the Sun.

2 There are eight planets in the Solar System:

Mercury	Mars	Uranus
Venus	Jupiter	Neptune
Earth	Saturn

3 Each planet moves in a large oval path called an orbit. It also rotates on its own   

        axis.

4 The time taken by the planets to make one complete movement round the Sun 

        depends on their distance from the Sun.

5     The table shows the relationship between the distance of planets from the Sun and 

       the time taken by the planets to orbit the Sun