As you probably know, the New Moon sets at roughly the same time as the sun sets. As the waxing crescent moon begins to appear after New Moon, the lunar observer has the opportunity to catch a glimpse of an emerging crescent. The goal is to see how young a moon can be seen with the naked eye or with the aid of some optics. These crescents set soon after the Sun; the smaller the percentage of the moon visible, the less time you will have to see it as it will set soon after the Sun. One

of the challenges in seeing these crescent moons is that they are only visible in the twilight sky near the Sun. As the crescent becomes larger with passing days, the moon will set progressively later than the sun and will become a feature of the night sky. Of course, the cycle repeats every month.

The Crescent Moon Visibility screen lists the times and dates of such crescents as seen from your location for the selected year range. The calculations look for any crescent that's illuminated between 0.25% and 12%, although this can be changed by altering the on-screen defaults. Dates and times will be updated when the ENTER key is pressed.

This screen tells you how long (in minutes) you've got to see the crescent before it sets after the Sun and the percentage of the moon illuminated. Very thin crescents may be impossible to view or may require the aid of telescopes or binoculars. It should be noted that the record is a 13.5 hour-old moon. Times of Sunset and Moonset are also listed for reference.

The times shown take Daylight Savings Time into account during the Summer months and are displayed in local time.

Double-clicking on any of the lines in the display will set LunarPhase Pro to that time and date so you can further examine the lunar circumstances for that occasion.