Today's watch sounds like it should be on a Nasa mission to land on the moon rather than tell the time!
The reason for the name is that one of the four indicator dials on the face is for the moon phase. It has a picture of the moon that travels across a semicircular window, being a full moon in the middle, a new moon when it has disappeared, and a part moon when it is partially obscured. The face also has 3 other small dials covering day (left), date (top), and month (right). The watch itself is a 3 hand dial in a square case, and uses a 6300 module.
It is part of the Citizen Trans Continents range which seems to have a retro 60s travel theme, but doesn't appear in any of the Citizen dealer catalogues of the time.
This watch was made in 2003, but I don't know how long it was on sale for.