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So if you can get your hands on a large orange, with a diameter of approximately 83 millimeters, then you have a perfect scale model for the Earth.

You now also know the scale diameters for all of the other planets, so you can get about making a scale model of any of them.

It’s useful to try and think of some objects that might be appropriate for your own scale version of each planet.


There are some approximations shown here. All of them are selected so that they are objects you can relate to from a size perspective.


They are all within 10% of the exact diameter size that the scale model requires. The same object is used for both Uranus and Neptune as both planets are very similar in size in reality.


While not perfectly accurate they are close enough to give you a good indication of their size relative to each other and relative to the "Big Ball" which represents the Sun.


To help appreciate the size of the objects themselves, a scaled image of a 12-inch (30.5 cm) ruler is included alongside. The Moon is also shown on the same scale, and additionally below on an enlarged scale. A large marble (or "bowler") is a good approximation for the Moon.

Could you find, or make, an exact model for any of the objects?

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