The Orbiting Solar System kit allows you to create a a mechanical model of the solar system. Wind it up and watch the planets revolve around the sun.Made for Thames and Kosmos , assemble this complex machine, also known as an orrery, using snap-together plastic parts to learn how the gears and wind-up mechanism work to spin the model. Detail each planet with colourful, realistic-looking printed planet graphics. Discover how a special type of gear called a planetary gear is used to simulate the mesmerising motion of the solar system. Learn about the order of the planets, their relative sizes, their rates of revolution around the sun, their appearance, and other planetary facts. Bonus: There's a built-in expansion slot in case the mysterious Planet Nine is discovered This kit includes full-colour step-by-step illustrated assembly instructions.+ Build a colourful model of the solar system.+ Wind-up engine sets your planets in motion around the sun - no batteries required+ Learn about the planets' celestial orbits.+ Explore fundamental gear mechanics; planets travel at different speeds depending on the gear ratio. Build a colorful model of the solar system.Wind-up engine sets your planets in motion around the sun - no batteries requiredLearn about the planets' celestial orbits.Explore fundamental gear mechanics; planets travel at different speeds depending on the gear ratio.