The moon goes through eight different phases as it orbits the Earth. These phases are:
* New Moon
* Waxing Crescent
* First Quarter
* Waxing Gibbous
* Full Moon
* Waning Gibbous
* Third Quarter
* Waning Crescent
How the Phases of the Moon Change Over Time
The phases of the moon change over time because of the way that the moon orbits the Earth. As the moon orbits the Earth, it reflects sunlight back to Earth. The amount of sunlight that is reflected back to Earth depends on the position of the moon in its orbit.
* New Moon: During a new moon, the moon is located between the Earth and the Sun. This means that the side of the moon that is facing the Earth is not lit by sunlight. As a result, the moon appears dark from Earth.
* Waxing Crescent: After a new moon, the moon begins to move away from the Sun. As it does, more and more of the side of the moon that is facing the Earth becomes lit by sunlight. This causes the moon to appear to grow in size.
* First Quarter: When the moon is at a right angle to the Sun and the Earth, it is said to be in its first quarter. At this point, half of the side of the moon that is facing the Earth is lit by sunlight.
* Waxing Gibbous: After the first quarter, the moon continues to move away from the Sun. This causes more and more of the side of the moon that is facing the Earth to become lit by sunlight.
* Full Moon: When the moon is opposite the Sun in the sky, it is said to be full. At this point, the entire side of the moon that is facing the Earth is lit by sunlight.
* Waning Gibbous: After a full moon, the moon begins to move closer to the Sun. This causes less and less of the side of the moon that is facing the Earth to become lit by sunlight.
* Third Quarter: When the moon is again at a right angle to the Sun and the Earth, it is said to be in its third quarter. At this point, half of the side of the moon that is facing the Earth is lit by sunlight.
* Waning Crescent: After the third quarter, the moon continues to move closer to the Sun. This causes less and less of the side of the moon that is facing the Earth to become lit by sunlight.
The moon completes one orbit of the Earth every 27.3 days. This means that the phases of the moon repeat themselves every 27.3 days.
