In order to build our solar system model, we had to create a number of scale models of the smaller planets, as well as dwarf planets. Each object consists of various sized balls covered with paper mache to build them to the appropriate size. All planets used in the model (except the four largest) are 30 million to one.
Making a scale planet is a fairly simple task, you can make Pluto over a few weekends, Venus will take several weeks as you need to allow the paper to dry after 10 to 20 mm of layering. In the image below, I have laid out my finished models of Mercury, Venus, Earth (commercial 400mm, 16 inch, Earthball) and Mars.
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