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The Phases of the Moon & Times

The phase of the moon is determined its revolution around the Earth and how much of the moon's visible face is illuminated by light reflected from the sun. The phases cycle during the span of 28½ days, which is the amount of time it takes for the moon to orbit the Earth entirely.

New Moon
- During the new moon, the satelline is directly between the Earth and the sun. This means that the part of the moon that is illuminated is facing directly away from the earth. The moon is dark at this time and is not visible. This occurs on the first day of the new cycle.
Waxing Crescent
- The waxing crescent describes the moon as it slowly comes into view. First it appears as a sliver of light, and then it gradually grows over the course of a week. The term "waxing" refers to the fact that the moon is growing.
First Quarter Moon
- By the end of the first week, a quarter of the moon is visible. At this point, half the illuminated face of the moon can be seen.
Waxing Gibbous
- During the second week, the moon moves through the gibbous phase, when more than a quarter of the moon is visible, but before the full moon is visible.
Full Moon
- Two weeks into the 29 day cycle, the moon is fully visible from the earth. This means that the visible face of the moon is a full circle.
Waning Gibbous
- Over the third week, the visible portion of the moon shrinks. This period is known as waning gibbous, with "waning" referring to the moon's shrinking light.
Last Quarter Moon
- The waning quarter moon appears during the third week of the cycle, and a quarter of the moon is again visible.
Waning Crescent
- At the beginning of the fourth week of the moon cycle, only a sliver of the moon is visible. This phase is called the waning crescent moon. After the waning crescent moon, the light diminishes until it is entirely gone, which leads to the new moon.

Astronomy