Understanding Moon Phases: The 8 Stages
The moon phases are the changing shapes of the Moon we see from Earth as it orbits our planet each month. These phases occur because the Moon’s position relative to the Earth and Sun constantly shifts, changing how much of its sunlit surface is visible to us.
Each phase, from new moon to full moon and back again, represents a different portion of the Moon illuminated by the Sun.
There are a total of eight moon phases:
- New Moon
- Waxing Crescent
- First Quarter
- Waxing Gibbous
- Full Moon
- Waning Gibbous
- Last Quarter Moon
- Waning Crescent
Current Moon Phase:
Below, you’ll find a handy calendar showing the current moon phase for this month. You can cycle through different months (and years) to see the date of future full moons.
The Moon’s Orbit
It may help to know a little about the moon’s orbit to understand what is happening during each of the moon’s phases.
It takes the moon the same amount of time to orbit the Earth as it does to complete a full rotation on its axis (i.e., approximately 27 Earth days). This orbit has been affected by the Earth’s gravitational pull, which has helped to slow the moon’s orbit, causing the moon and Earth to be synchronized.
Due to this synchronization, we only ever see the ‘near side’ of the moon from Earth, which is only half of the lunar total surface. The amount of near side that is seen depends on the amount of available sunlight.
The Moon spins on its axis at the same rate that it orbits Earth (about once every 27 days). This synchronized motion, called tidal locking, means the same hemisphere (the “near side”) always faces us. The far side isn’t permanently dark; it simply faces away from Earth as both sides take turns catching sunlight.
What Causes the Moon Phases?
As mentioned above, the moon goes through a cycle of phases each month as it orbits Earth, and each phase is dependent on the moon’s position in relation to the Sun.
The moon phase we see from Earth is the portion of the moon that is lit up by the Sun, which can range from zero percent illuminated (new moon) to 100 percent illuminated (full moon).
This means our view of the illuminated portion of the moon changes as the moon orbits around Earth, working its way through the different moon phases.
For example, in the new moon phase, the moon is completely shadowed. As the moon continues to orbit Earth, the visible area grows (i.e., waxes) to a fully illuminated moon. The phases will then reverse, where the visible area decreases (i.e., wanes).
Moon Phases in Order
Here is a detailed breakdown of each of the eight moon phases, along with a picture of each phase for reference.
New moon:
The moon is between Earth and the Sun; the moon’s shadow faces Earth.
- Moon phase type: Primary
- Percentage of Illumination: Zero percent
- Description: We cannot see the moon
It is called a “new moon” because it marks the beginning of a new lunar cycle. During this phase, the Sun and the Moon are in conjunction, aligned on the same side of the Earth.
During the new moon phase, the moon appears completely dark as we are facing its shadowed side, which is not illuminated by direct sunlight. This is the best time to observe and photograph deep-sky objects.
Waxing Crescent:
- Moon phase type: Intermediate
- Percentage of Illumination: Zero to 50 percent
- Description: a thin crescent of light on the right
The waxing crescent moon phase occurs between the new moon and the first quarter phase. This phase showcases a beautiful crescent-shaped moon, appearing on the right side (in the Northern Hemisphere).
As each day passes, the illuminated area on the moon gradually widens, covering more of the moon’s surface until the first quarter phase.
First-quarter:
The Moon is at a right angle with respect to the Sun from Earth.
- Moon phase type: Primary
- Percentage of Illumination: 50 percent
- Description: the right side is illuminated
The first-quarter moon phase can be a bit confusing to beginners. It is named this because, at this point, the moon has completed approximately one-quarter of its orbit around the Earth.
However, from our perspective, half of the moon’s surface is illuminated (not a quarter). Some people refer to the first and last quarter moon phases as ‘Half Moon’.
Waxing Gibbous:
- Moon phase type: Intermediate
- Percentage of Illumination: 50 to 100 percent
- Description: halfway between a half-moon and a full moon (right side is illuminated)
The waxing gibbous moon phase occurs between the first quarter and full moon phases. It is characterized by the Moon being more than half illuminated, but not yet fully.
The word “gibbous” is a Latin word that refers to a shape that is convex or bulging outward on one side, resembling a hump or a rounded curve.
Full moon:
The moon is on the opposite side of Earth from the Sun; the illuminated side faces Earth.
- Moon phase type: Primary
- Percentage of Illumination: 100 percent
- Description: The entire moon is illuminated
During a “full moon”, the entire disk of the moon appears to be illuminated from our vantage point on Earth. The Sun and Moon are in opposition, positioned on opposite sides of the Earth.
If the full Moon’s position aligns correctly with the Sun and Earth, it can pass through the Earth’s shadow, resulting in a lunar eclipse.
Each month’s full moon has a different name. For example, the full moon in September is known as the “harvest moon”.
Waning Gibbous:
- Moon phase type: Intermediate
- Percentage of Illumination: 100 to 50 percent
- Description: halfway between a half-moon and a full moon (left side is illuminated)
The waxing gibbous moon phase takes place between the full moon and the last quarter. It depicts the Moon when it is more than half illuminated, but not completely.
At the beginning of this stage in the Northern Hemisphere, we see a nearly fully illuminated disk, except for a small sliver on the right side that remains in darkness.
Last quarter moon:
The moon is at a right angle with respect to the Sun from Earth.
- Moon phase type: Primary
- Percentage of Illumination: 50 percent
- Description: The left side is illuminated
The last quarter moon phase is named this because the moon has now completed approximately three-quarters of its orbit.
In the Northern Hemisphere, the left half of the moon is lit. Some people refer to this moon phase as the “Third Quarter”.
Waning Crescent:
- Moon phase type: Intermediate
- Percentage of Illumination: 50 to zero percent
- Description: a thin crescent of light on the left
The waning crescent moon phase falls between the last quarter and the new moon phase. At the beginning of this stage (in the Northern Hemisphere) , the moon’s entire left side is almost fully illuminated.
As the days pass, the illuminated area gradually diminishes, covering less and less of the Moon’s surface until it appears as a very thin crescent on the left side.
The best time to view the moon in its late waning crescent stages is before sunrise, when the sky is still dark in the morning.
The dates and times of these phases change each month, given the amount of time it takes the Moon to orbit Earth (27 days) and the approximate time it takes to complete one cycle of phases (29.5 days), known as a synodic month.
The intermediate phases last, on average, a quarter (i.e., 7.4 days) of the synodic month, while the long duration between full moon and new moon (or vice versa) lasts approximately 15 days.
How Each Moon Phase Affects Rise/Set Times
Each phase of the Moon rises and sets at predictable times based on its position relative to the Sun.
During a new moon, the Moon lies between Earth and the Sun, rising and setting almost in step with the Sun itself. It’s lost in daylight and invisible to the naked eye.
A first-quarter moon rises around midday and sets near midnight, giving you a bright half-moon high in the evening sky.
The full moon appears opposite the Sun, rising at sunset and setting at sunrise, dominating the entire night.
By the last quarter, the Moon rises close to midnight and lingers into the morning hours.
How Latitude & Season Change Appearance
Your location on Earth changes how the Moon’s path arcs across the sky. Near the equator, the Moon rises and sets almost vertically, spending less time low on the horizon.
From mid-northern latitudes, like much of North America, the Moon’s path cuts across the southern sky at a noticeable angle. Sometimes it climbs high, and other times it hugs the horizon, depending on the season.
During winter, the full moon rides higher in the sky (because it’s opposite the low winter Sun), while in summer it tracks lower. The opposite happens for southern observers.
These differences explain why certain phases seem brighter or more photogenic at specific times of year.
Southern Hemisphere & Global Differences
Although the Moon’s eight phases are the same for everyone on Earth, the way we see them differs depending on where we stand. Observers in the Northern and Southern Hemispheres share the same lunar schedule (new, crescent, quarter, gibbous, and full), but the Moon’s orientation and path across the sky appear reversed.
In the Northern Hemisphere, the waxing Moon (when it’s growing brighter) appears illuminated on the right-hand side, while the waning Moon (fading toward new) is lit on the left. South of the equator, this is flipped: the waxing Moon glows on the left, and the waning Moon on the right.
This mirror effect occurs because people in opposite hemispheres effectively view the Moon from opposite angles on the globe. The phases themselves are identical; the only thing that has changed is our perspective. If you could stand on the equator, you’d actually see the Moon’s crescent lying almost flat, shaped like a bowl.
The Moon’s path across the sky also varies dramatically between hemispheres. In mid-northern latitudes, the Moon rises and sets toward the southeast and southwest, tracking relatively low across the southern sky. From southern latitudes, it’s the opposite: the Moon rises in the northeast, sets in the northwest, and arcs high across the northern sky.
Blue Moon, Supermoon & Micromoon
Not every full moon is created equal. Some months feature special variations that add a bit of drama to the lunar calendar, most famously the Blue Moon, Supermoon, and Micromoon. Each one still fits into the regular cycle of moon phases; they simply occur under particular orbital or timing conditions.
A Blue Moon isn’t actually blue in color; it’s a calendar term. It describes the second full moon within a single calendar month (or, more rarely, the third full moon in a season that has four). Because the lunar cycle averages 29.5 days, this happens roughly once every two to three years.
A Supermoon happens when a full moon coincides with the Moon’s closest point to Earth in its orbit, known as perigee. The result is a full moon that can appear up to 14 percent larger and about 30 percent brighter than average. These are ideal nights for wide-angle nightscapes or reflection shots where the Moon dominates the scene.
The apparent size of the moon during apogee vs. perigee. NASA’s Scientific Visualization Studio.
Conversely, a Micromoon occurs when the full moon happens near apogee, the Moon’s farthest point from Earth. It looks slightly smaller and dimmer, though the difference is subtle to the naked eye.
All three phenomena (Blue Moon, Supermoon, and Micro-moon) take place during the full moon phase. They don’t add new phases to the lunar cycle; they simply make certain full moons stand out, offering photographers and skywatchers an extra reason to look up.
Moon Phases & Astrophotography
As an astrophotographer with over 15 years of experience, understanding the timing and position of each moon phase helps me plan my photography sessions. Even if the sky is clear, the current moon phase will have an impact on your astrophotography.
A full moon (or nearly full moon) can make astrophotography difficult because it reflects bright sunlight into the sky, washing out faint deep-sky objects. In general, it reduces the overall contrast and detail in images you capture.
If you’re shooting a deep-sky object (like a galaxy or nebula), aim for the days surrounding the new moon when the sky is darkest. While the new moon phase is best for all deep-sky objects, it is especially important when capturing a broadband target such as a reflection nebula, dark nebula, or galaxy.
If you’re capturing the Moon itself, plan for when it’s high above the horizon and fully illuminated, or better yet, time it near the horizon for dramatic landscapes with twilight color. The image below was captured using a DSLR camera and lens on a simple tripod.
Capturing the moon in its waxing gibbous/full moon phases allows you to add foreground interest as it rises in the evening sky.
You can also capture the moon up close with a telescope to reveal the moon’s cratered surface. The telescope acts as a long-focal-length telephoto lens to bring the moon into sharp focus for a detailed look.
One of the easiest ways to capture a fantastic picture of the moon is to use a smart telescope. These devices make it easy to find the moon in the sky, center it, and take a sharp photo with the proper exposure.
Example photos of the moon taken using popular smart telescopes. Notice the size difference depending on the model you’re using.
Photographing Planets During a Full Moon
Planets are much brighter than deep-sky objects like galaxies and nebulae. Large, bright planets (from our perspective on Earth) like Venus, Mars, Jupiter, and Saturn are relatively easy to photograph using modest equipment.
The nights surrounding the full moon are a great time to photograph our solar system neighbors at high magnification. Here is a picture of the planet Jupiter captured with a bright (80% illuminated) moon nearby.
Planetary astrophotography is unaffected by a bright moon.
You can use moonlight to help illuminate a nighttime landscape, creating an image that reveals stars and constellations, and a moonlit foreground below. A rising full moon offers a fantastic opportunity to capture the moon with interesting foreground details.
The hauntingly beautiful colors of a full moon as it passes through Earth’s atmosphere make for a dramatic scene. The image below was captured from a farmer’s field as a “supermoon” rose in the fall.
The full moon rises over a farmer’s field.
Related Post: How to Take Great Pictures of the Moon (with examples)
Online Moon Phase Calendars
There are many websites and mobile stargazing apps available today that will provide a moon phase calendar. If you are interested in skipping the complicated mathematical formulae for determining the cycle, you may want to look at a few of these resources. A few are listed below for reference.
The Moon: Calendar Moon Phases (Apple/Android)
Features: moonrise, moonset, moon phases, lunar days, illumination, distance, and position. Includes bonus features.
My Moon Phase – Lunar Calendar (Apple/Android)
Features: view the moon cycle for any date, see how cloudy the sky is expected to be, the moon’s distance from Earth, receive notifications when the moon reaches a particular phase, etc.
Time and Date (Website)
Features: graphic depiction of moon phase for your location, including dates for the next full moon and first-quarter phases. It also breaks down the moon phases for the year into the new moon, first quarter, full moon, and third quarter for your location and provides a separate graphic showing this information.
Frequently Asked Questions about The Moon
The eight main moon phases, in order, are: new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last (third) quarter, and waning crescent. This complete cycle takes about 29.5 days.
Moon phases change as the Moon orbits Earth and sunlight illuminates different portions of its surface. The phase you see depends on the relative positions of the Moon, Earth, and Sun.
Each of the eight phases lasts roughly 3½ days, though exact timing varies slightly month to month. The entire lunar cycle repeats every 29.53 days.
For deep-sky imaging, the new moon is ideal because the sky is darkest. For lunar photography, first quarter or waxing gibbous phases offer the best surface contrast and sharp shadows along the terminator.
A supermoon occurs when the full moon coincides with the Moon’s closest approach to Earth (perigee). It can appear up to 14 percent larger and 30 percent brighter than a typical full moon.
Observers in the Southern Hemisphere view the Moon “upside-down” compared to Northern Hemisphere viewers because they’re on the opposite side of Earth’s globe. Waxing and waning phases appear mirrored.
Bright phases, such as the full moon, reduce sky contrast, making faint deep-sky objects harder to see. Planning your sessions around the new moon or crescent phases ensures darker skies for astrophotography or visual observing.
A blue moon isn’t blue in color—it simply refers to the second full moon within a single calendar month (or occasionally, the third full moon in a season with four).
You can check the current phase using an interactive moon phase tool or an astronomy app that shows illumination and rise/set times for your location.
That’s an optical illusion called the “moon illusion.” The Moon’s size doesn’t change; our brains compare it against terrestrial objects like trees or buildings, making it appear bigger.
Helpful Resources:
- The Full Moon Names for Each Month
- How to Photograph a Lunar Eclipse
- Moon Phases in 2021 (APOD Videos)
- Solar and Lunar Eclipses Worldwide (Time and Date)
- What Makes a Halo Around the Moon?
