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Moon Phases


The Moon passes through its "phases" as it orbits around the Earth.
Half of the Moon (the side facing the Sun) is fully lighted.
We can see only the half of the Moon that is nearest to the Earth.
As the Moon orbits every 29.5 days, we see the illumination cycle across its face.
When the Moon is between the Earth and the Sun, the lighted half points away from Earth. This is a New Moon.
When the Earth is between the Moon and the Sun, the lighted half points towards Earth. This is a Full Moon.
When the illuminated potion is growing, the Moon is said to be Waxing.
When the illuminated potion is shrinking, the Moon is said to be Waning.
When less than half the face is illuminated, we call it a Crescent Moon.
When more than half the face is illuminated, we call it a Gibbous Moon.