Build a Moon Phase Clock That Looks Like The Real Thing

The moon is a beautiful thing that has captivated humanity for centuries, particularly before the advent of television and the Internet when there was nothing else to watch. [JCM_MatSci] developed a clock which tracks the phases of the moon, so you can keep an eye on the state of Earth’s satellite without even having to turn your gaze to a window.

The clock relies on a simplified model of the lunar phases, based around the synodic month which averages 29.530588 days. For non-astronomical purposes, it’s pretty much close enough. The clock uses a high-torque off-the-shelf quartz movement in order to move a 3D-printed geartrain and attached moon assembly. The gears step down the output from the clock to turn the ersatz Moon to display the appropriate phase.

It’s a neat gift for Moon buffs out there, and we’re sure there are still a few even if nobody’s been since 1972. We guess it’s kind of like one of those national parks that everyone loves from their childhood but never visits anymore.

If you have visited the moon recently, however, be sure to drop us a line. We (and a few other million people) have some questions for you.