Practical 1

Modelling the solar system in the school yard

In this activity, you will work with scales to position planets on the school yard in positions corresponding to their relative distances from the sun. It is best if you work in groups.

Modelling planets

You could do this very simply by just marking position (eg. with chalk), or by using a simple model, or by positioning members of your group correctly!

If you are making a model, you will need to know the size of the planet, especially its diameter, and because planets are huge, you will need to work to a scale. Your teacher will advise you about this.

The planet diameters (km) are indicated in the table below:

Finding planet position

Your teacher will:

• Let you know about the scale you need to use for planet distance. This will be different to the scale you used for planet size (because distances between planets are even bigger than the planets themselves).
• Decide on a position for the sun.

Each group will be assigned a planet (and/or moon). The group will then work out the scaled distance for its planet, and hence where the planet should be positioned relative to the 'sun' on the yard. The distances from the sun for each planet are shown in the table below ( x 10⁶ km ):

You could then enact the orbital pattern of your planet, which will help you understand why distances vary between planets at different times (eg. Earth to Mars)