Comment by thih9
Mechanical watch:
https://monochrome-watches.com/the-elegant-mixture-of-time-a...
Prague’s astronomical clock does that too:
https://en.wikipedia.org/wiki/Prague_astronomical_clock#Moon
More about spherical moonphases:
https://www.the1916company.com/blog/variations-on-the-moonph...
A smartwatch complication:
https://www.david-smith.org/blog/2019/09/26/moon-plus-plus/
> Geneva Moon seeks to provide a highly accurate, visually pleasing indication of what the moon looks like right now, right where you are. My goal was to make it so that if you look down at your wrist and then up into the sky the images you see should match.
i meant the mechanism not the idea of moon phase. He uses an interesting variation on an iris shutter to manage the transition of the terminator from C to D