The Lego Technic planet earth and moon in orbit space set ticks all my boxes and then some. When I was looking for a model of the moon's orbit around earth I first looked for fully-assembled scientific models that I could keep on my desk to show my young nephews. But after a little internet sleuthing, I realized many of these models are fragile, large and cumbersome to younger space scientists.
So naturally I turned to Lego. This 526-piece Technic set does several things absolutely amazingly. The set is full of gearing that must be accurately but easily assembled, with shafts and spindles that rotate, all basic engineering knowledge that is fun to acquire (at any age, I might add!).
Next, the set itself is quite accurate. No, it's not the perfectly-to-scale model I was looking for at the beginning, but that was never really feasible for keeping in the home anyway. With a crank of the handle the earth orbits the sun, and the moon round the earth too, but the sun also revolves and so mimics the real-life movements.
A month sticker wraps around the circular base and a handy indicator shows where you are in the year, to help explain why summer and winter comes to the northern hemisphere when it does. I bought this with my own money and I love it. It's fun to put together on your own or as part of a group and better yet, it's scientifically informative and beautiful at the same time.
Lego planet earth and moon in orbit: Build This 526-piece build is more complex than larger-piece .