This is the chronograph that tracks the phases of the moon, moonrise, moonset, sunrise, sunset, and more, allowing amateur astronomers to plan for the best viewing conditions for observations. The watchface employs a unique LCD consisting of 96 separate sections arranged in a ray pattern originating at the center of the watchface. Each section accounts for 15 minutes of time and matches to the watch's 12-hour bezel, covering a full 24-hour day. Once you select your location from 583 pre-programmed cities, these sections are shaded to depict sunset and hours of darkness and left bright to depict sunrise and hours of daylight (an adjacent circular display tracks moonrise and moonset). A 24-hour hand moves precisely around the 12-hour bezel to cunningly depict the current time. The top of the watchface displays the digital time and the bottom has a lunar display that depicts all eight phases of the moon (New Moon shown). A 24-hour bezel allows you to keep track of time in another time zone. Its quartz oscillator provides accurate time keeping, and its stainless steel case employs double O-rings for the pushers and crown for a 10 ATM rating. Battery included. 1 3/4" Diam. (6 1/2 oz.)