The size of the solar system
size of the solar system
You can read about the diameters
of the Earth, Sun, Moon and Planets in thousands of kilometres
and the distances between them in millions of kilometres, but the
only real way to understand the size of the solar system
is to make a model.
Once you have made the model you will understand why you cannot make a scale drawing of the solar system, unless you happen to have a piece of paper bigger than a football field....
This model assumes you and your
friends are all about eleven years to thirteen years old - if you are
all much older or younger the number of paces between the
planets will be different.
You will need
- A number of friends,
at least six but up to eleven
- A large fairly flat field. A football field will take you as far as Mars but several football fields
will be needed if you are going to include all the
planets as far as Neptune
- A football
- A large lump of
plasticine (or other modelling clay)
- A tablespoon of granulated sugar or
table salt (in a container!)
- A ruler (at least 100mm)
pieces of card or paper, one for each child, and a
felt tip pen
- In the full model Neptune is more than a thousand paces from the Sun, so if you do have a big enough field to go as far as Neptune mobile phones might be useful for you to keep in touch with each other
You all start together in one corner of the field. Label the pieces of card as you go.
- The Sun
is a football in this corner.
is a lump of plasticine about 1mm in diameter 15 paces
from the Sun
- Venus is a lump of plasticine nearly 2mm
in diameter 12 paces beyond Mercury
- The Earth is a lump
of plasticine nearly 2mm in diameter 10 paces beyond Venus
Moon is a lump of plasticine about 0.5mm in diameter 6
cm from the Earth
- Mars is a lump of plasticine about
1mm in diameter about 20 paces beyond the Earth
- The asteroids
are a tablespoon of salt or sugar 48 paces beyond Mars - in real life they are spread out in a circle all round the Sun.
- Jupiter is a lump of plasticine 20mm in diameter 93
paces beyond the asteroids
- Saturn is a lump of plasticine about
17mm in diameter 162 paces beyond Jupiter
- Uranus is a lump
of plasticine about 7mm in diameter 360 paces beyond Saturn
is a lump of plasticine about 7mm in diameter 410 paces
Neptune is therefore more than 1000 paces from the Sun. On this scale it
will take you at least a month to walk to our
You can find out more about the planets by going to the Planets Page of my Web Site. This Page also explains why Pluto is not a Planet any more.
© Barry Gray September 2008