Make a model to show how the Earth orbits the Sun
â€¢ Large room or outdoor area (big enough to walk 23 metres in a straight line)
â€¢ Long tape measure (or piece of string 23 metres long)
â€¢ A pin (the dressmakerâ€™s type with a glass head).
This activity explores the relative size of the Sun and the Earth and the distance between them,
as well as the time it takes for the Earth to orbit the Sun. The scale used is about 1:40,000 of the
What to do:
1. Show the pack the football and explain that this represents the Sun. The actual size of the
Sun is 1,380,000 kilometres or 863,000 miles across (ie. diameter)
2. Ask the pack how big they think the Earth would be if the football represents the size of the
3. Reveal the answer by showing the pack the pin head. The actual size of the Earth is 12,800
kilometres or 8,000 miles across. The Sun is 108 times bigger than the Earth.
4. Then ask the pack how far apart they think the Sun and the Earth should be. If you hold the
football, you can ask them to stand in the place they think the Earth should be.
5. Use the piece of string to reveal the answer â€“ the Earth would be 23 metres from the Sun.
The Earth is actually 149 million kilometres or 93 million miles away from the Sun.
6. You can then ask one cub to hold the football and be the Sun, and another to be the Earth.
Explain that the Earth travels around the Sun and that it takes a whole year to complete one
â€˜orbitâ€™. Using our scale model, it would take about 13 minutes. You can ask the Earth to walk
around the Sun and come back to where it started, staying 23m away. Try to make this take
You could find out the diameter and distance of the Moon from the Earth and work out how
long it would take for the Moon to orbit the Earth.