moon phase calendar
This moon calendar or moon schedule helps you find the Moon’s phase for any day. Select a month and year to view the lunar phases throughout the month.
About the Moon Calendar
The Moon phase calendar shows how the Moon changes throughout the month as it orbits Earth. It includes the eight main lunar phases—New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, and Waning Crescent—along with the dates and exact times of the major phase changes.
The Moon does not produce its own light. We see it because sunlight reflects from its surface, and the amount of the illuminated side visible from Earth changes as the Moon moves around our planet. A complete cycle from one New Moon to the next takes about 29.53 days, known as the synodic month.
The calendar can help you find the dates of upcoming New Moons, Full Moons, and quarter phases, and understand where the Moon is in its lunar cycle on any given date. For the best observing experience, you can also use the Moon’s phase and illumination to plan stargazing, lunar photography, and other nighttime observations.
Understanding the Moon’s Phases
The eight main Moon phases describe the changing appearance of the Moon as seen from Earth. During the waxing phases, the illuminated portion we can see grows each day. During the waning phases, it gradually becomes smaller.
A New Moon occurs when the Moon is positioned approximately between Earth and the Sun, while a Full Moon occurs when the Moon is approximately opposite the Sun with Earth between them. The First Quarter and Last Quarter phases occur between these two points in the lunar cycle.
The phases are part of a continuous cycle rather than eight separate states. The Moon’s appearance changes slightly from one day to the next as it moves through its orbit.
Why the Moon Phase Changes
The Moon is constantly orbiting Earth while sunlight illuminates half of its surface. As the Moon travels around Earth, our viewing angle changes, allowing us to see different portions of its sunlit half.
The Moon completes one orbit relative to the distant stars in about 27.3 days, but it takes about 29.53 days to return to the same phase. The difference occurs because Earth is also moving around the Sun, so the Moon must travel a little farther in its orbit to reach the same position relative to the Sun and Earth.
How to Use This Moon Phase Calendar
Use the calendar to find the exact dates and times of the major lunar phases throughout the year. If you’re planning to observe the Moon, remember that the exact phase time is only one part of the picture—your location, moonrise and moonset times, weather, and local sky conditions also determine when and how the Moon will appear.
For stargazing and deep-sky observation, the days around the New Moon generally provide the darkest skies because there is little moonlight. Around Full Moon, the bright lunar surface can make faint stars and deep-sky objects more difficult to see, but it provides excellent conditions for observing the Moon itself.