The Sun–Earth orrery
Engineers (Advanced), mission M6 Space Machines, lesson 1 of 6.
Hook
Why do we have day and night, and seasons? A machine can show it.
Fair test
Count Earth spins per orbit on the model. How close to 365 is it? Why not exact?
Bonus challenge
Shine a torch as the Sun. Where on Earth is it midday?
The build
- 🌍 Sun-Earth-Moon Orrery: Push the arm round: the Earth circles the Sun, spinning as it goes, with the Moon in tow. (level 4 of 5, about 35 minutes, 12 steps)