Moon Phases
The four major phases of the moon are the new moon, first quarter, full moon, and last quarter.
A new moon is the first lunar phase that happens about once a month or 29.53 days on average. The moon itself is not visible, though you may be able to “see” it because it blocks the visibility of the stars behind it.
A full moon occurs when the Earth is directly between the Sun and Moon, so that the moon appears completely illuminated. It happens about once a month, or 29.53 days on average.
The first quarter moon occurs between the new moon and full moon, and the last quarter moon occurs after the full moon and before the next new moon.
