Moon Phases
Did You Know?
The Moon completes a full cycle of phases in 29.5 days!
What Are Moon Phases?
Moon phases are the changing appearances of the Moon as seen from Earth, caused by the relative positions of the Sun, Earth, and Moon. As the Moon orbits Earth, different portions of its sunlit side are visible to us. The cycle includes new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, and waning crescent phases.
The Cycle
The complete cycle of moon phases, called a synodic month, takes 29.5 days. During a new moon, the Moon is between Earth and the Sun, so its dark side faces us. As the Moon moves in its orbit, we see more of its sunlit side until full moon, when Earth is between the Sun and Moon. Then the cycle reverses.
Cultural Significance
Moon phases have been important to human cultures for thousands of years. They've been used for calendars, navigation, and religious observances. Many cultures have myths and stories about the Moon's changing appearance. The phases also affect tides on Earth, with spring tides occurring during new and full moons.
Amazing Facts
A full moon cycle takes 29.5 days
This fact reveals the incredible scale and wonder of our universe.
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Moon phases affect ocean tides
This fact reveals the incredible scale and wonder of our universe.
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The same side always faces Earth
This fact reveals the incredible scale and wonder of our universe.
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Moon phases have been used for timekeeping
This fact reveals the incredible scale and wonder of our universe.
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