wmMoonClock(1) on Linux
The text e6b05647e2b1, as Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy) shipped it.
Dockable Moon Phase Clock
Flags it lists
-
-bc -
-dc -
-display -
-h -
-lat -
-lc -
-lon -
-low