Waning Crescent Moon Picture
What is a waning crescent moon eclipse? The waning crescent moon, sometimes called an old moon, is defined to occur when the Moon is nearly, but not precisely, on a line with the Earth and Sun. This means that part but less than one-half of the Moon is illuminated by direct sunlight, creating a crescent moon. Because the fraction of the Moon’s disk that is illuminated is decreasing, we consider the Moon to be “waning.” This waning crescent moon picture illustrates this spectacular event.