I’ll be honest, even after decades, LEGO still holds the potential to absolutely amaze me with its capabilities. The LEGO Sun Earth Moon Orrery is a stunningly detailed little kinetic machine that doesn’t just replicate the movement of the earth and moon around the sun, it also factors in the earth’s axial tilt, tracks moon phases, demonstrate solar and lunar eclipses, and aims at being as astronomically accurate as possible. Made from a staggering 2303 pieces, the Sun Earth Moon Orrery uses 70 Technic gears to allow the cosmic bodies to move realistically and can either be manually controlled using a hand crank or electrically via an RC motor.
In true Da Vincian fashion, the LEGO Sun Earth Moon Orrery is as ornate as it’s intricate. Multitudes of well-placed gears allow the miniature earth to rotate on its tilted axis while revolving around the sun, while the moon does the same, completing one rotating and revolution around the earth with each spin. Designed and built by LEGO creator ‘Marian’, the Orrery measures 10.6 inches wide if you count just the 12-faced faceted base (to celebrate the 12 months of the year), and a stunning 20.9 inches if you also factor in the moving earth and moon.
The kinetic orrery realistically models the rotational periods of the sun, earth, and moon along with the orbital periods of the latter two. The earth’s axial tilt lets you easily demonstrate concepts like seasons, solstices, and the change in the sun’s position based on which hemisphere you live on. It also helps accurately depict sunrises and moonrises, how solar and lunar eclipses work, moonphases, tidal locking, and even allows you to track solar and lunar calendars with stunning accuracy (especially for a LEGO kit).
While the LEGO Sun Earth Moon Orrery isn’t available as a standalone kit, you can buy it by checking out Marian’s inventory of parts on Rebrickable. Although do be warned, this fairly complex build comes with a 264-page instruction manual detailing the entire build process in an exhausting 436 steps!