Earth and Moon Orbit Model (LEGO 42179)

About this set

This is LEGO Technic 42179, the Earth and Moon Orbital Model, labelled LEGO TECHNIC on the box with set number 42179. Our records list 526 pieces and a difficulty of 3/5. The subject is a solar system astronomy model rather than a vehicle, and the finished build mixes black, orange, yellow, blue, white and grey parts: a rotating sun model at the centre, Earth and Moon models held out on support arms, and a base with rollers and a gear train, plus a crank and linkage on the side. When building, seat the base rollers and gear train first, then fit the support arms, and only then hang the Earth and Moon and set their positions relative to the sun; the crank linkage is the easiest link in the chain to fit backwards, so line up the angles as shown before pressing parts together. Turn the crank and the sun, Earth and Moon travel their orbits together. It suits anyone into astronomy who wants a hands-on desk display; at 3/5 it is manageable for builders with some Technic clutch experience.