A working model of the Sun, Earth and Moon, after W & S Jones of Holborn, 1794
Made by W & S Jones,
Holborn, London
1794
An orrery is a geared model of the Solar System. This one shows only the Sun, Earth and Moon. Turning the handle carries the Earth round the Sun once a year, while the Moon circles the Earth about twelve times.
Watch the Earth's axis as it travels. It always leans the same way in space, so the north pole tips toward the Sun in June and away from it in December. That lean is what makes the seasons. Sizes and distances are not to scale.