PHASES OF THE MOON

The revolution of the Moon around the Earth causes the Moon to appear to change shape in the sky. These different shapes are called "phases" of the moon. The Moon passes through a cycle of eight phases every 29.5 days. There is no definite starting point for the cycle, but phases follow one behind the other in a strict order. You will find images of each of the eight phases, as well as a breif description of each phase. The images reflect the order the phases are viewed from the earth.

Waxing Crescent

The visible moon is partly but less than one-half illuminated by direct sunlight while the illuminated part is increasing.

First Quarter

One-half of the moon appears illuminated by direct sunlight while the illuminated part is increasing

Waxing Gibbous

The Moon is less than fully illuminated but greater than half illuminatedby direct sunlight while the illuminated part is increasing

Full Moon

The visible moon is fully illuminated by direct sunlight.

Waning Gibbous

The Moon is less than fully illuminated but greater than half illuminatedby direct sunlight while the illuminated part is decreasing

Last Quarter

One-half of the moon appears illuminated by direct sunlight while the illuminated part is decreasing

Waning Crescent

The visible moon is partly but less than one-half illuminated by direct sunlight while the illuminated part is decreasing.

New Moon

The visible moon is not fully illuminated by direct sunlight.

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