What is a year on moon
What is a year on moon
When is the next full Moon?
Check the dates for every full Moon throughout the year, and learn about lunar phases, ‘supermoons’ and more
What is a full Moon?
A full Moon occurs when the Moon appears as a complete circle in the sky. We see it as a full orb because the whole of the side of the Moon facing the Earth is lit up by the Sun’s rays.
The Moon produces no visible light of its own, so we can only see the parts of the Moon that are lit up by other objects.
A small amount of light comes from distant stars and the reflection of light from the Earth (known as ‘Earthshine’). However the main source of light for the Moon is the Sun.
«In 2021 I really got into imaging the Moon at a distance with something in the foreground. In this case, it is people enjoying the Full September Harvest Moon as it rises behind Glastonbury Tor.»
«Here, the Snow Moon sets over Clifton Suspension Bridge in Bristol. This was a fluke of a morning. I hadn’t actually intended to head out to photograph the Moon and was on my way into town to walk the dog!»
«This is a 32-panel mosaic of the crescent Moon. The assembly process was particularly complex due to the lunar libration (wavering of the Moon as viewed from Earth), which changed during the two hours I spent shooting on that January evening. In this image you can see the most famous craters, rims, mountains, domes and seas of this lunar phase.»
«It’s always great to see the colours of the Moon teased out in an image and this one cranks it up to 11, showing our neighbour to be enormously complex.» — Steve Marsh, Art Editor at the BBC Sky at Night Magazine
«This aptly named image could almost be a model set from a 1950s/1960s science fiction television programme! The surreal atmosphere of this image is greatly enhanced by the high thin cloud and the monochrome palette with the Full Moon adding drama to the scene, either indicating serenity or impending doom (depending on the plot).» — Mandy Bailey, Astronomy Secretary for the Royal Astronomical Society, Open University lecturer and freelance science editor
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The Moon appears as different shapes in the sky depending on its ‘phase’, from new Moon to full Moon via ‘waxing’ (growing) and ‘waning’ (shrinking) moons. These phases are determined by the relative positions of the Sun, Earth and Moon.
If the Moon is between the Earth and the Sun in its orbit, then the back side of the Moon is lit up and the side facing the Earth is in darkness. This is called a new Moon.
If the Moon is on the opposite side of the Earth to the Sun, then the near side of the Moon will be fully lit up: a full Moon.
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How often does a full Moon occur?
A full Moon happens roughly every 29.5 days. This is the length of time it takes for the Moon to go through one whole lunar phase cycle.
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Is there a full Moon every month?
A month was originally defined to be either 29 or 30 days, roughly equal to the 29.5-day lunar cycle. However, some of our calendar months were later padded out with extra days, in order that 12 months would make up one complete 365-day solar year.
Because our modern calendar isn’t quite in line with the Moon’s phases, sometimes we get more than one full Moon in a month. This is commonly known as a blue moon.
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When is the next full Moon?
The next full moon is on 12 August at 2.36am in the UK. This is sometimes known as a ‘Sturgeon Moon’.
Check the calendar below to see all the full Moon dates in 2022.
Full Moon calendar 2022
| Full Moon date and time | Full Moon name |
|---|---|
| 17January (11.48pm) | Wolf Moon |
| 16 February (4.56pm) | Snow Moon |
| 18 March (7.18am) | Worm Moon |
| 16 April (7.55pm) | Pink Moon |
| 16 May (5.14am) | Flower Moon (total lunar eclipse) |
| 14 June (12.51pm) | Strawberry Moon (supermoon) |
| 13 July (7.38pm) | Buck Moon |
| 12 August (2.36am) | Sturgeon Moon |
| 10 September (10.59am) | Corn/Harvest Moon |
| 9 October (9.55pm) | Hunter’s Moon |
| 8 November (11.02am) | Beaver Moon |
| 08 December (4.08am) | Cold Moon |
All times show the time of the full Moon at the Royal Observatory’s home in London, either in GMT or BST depending on the time of year. For full details see the 2022 Guide to the Night Sky
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Why is there a full Moon in the middle of the day?
Some of the times included in the table show full moons happening in the middle of the day. How can this be?
While you can often see the Moon even during the day, it may at first seem odd to think of a full Moon occurring during daylight hours. However, there is a straightforward explanation.
The reason this happens is that the time refers to the exact moment when the Sun and Moon are aligned on opposite sides of the Earth. This moment is known as the ‘syzygy’ of the Sun-Earth-Moon system, and can happen at any time day or night.
The Moon will still look full either on the night before or the evening after the exact moment of ‘full Moon’.
What is a Supermoon?
The distance between the Moon and the Earth varies, because the Earth is not right at the centre of the Moon’s orbit and the Moon’s orbit is not a circle (it’s an ellipse).
The moment when the Moon is closest to the Earth is called a lunar perigee. When the Moon is furthest away it is known as a lunar apogee.
If the lunar perigee occurs very close to a full Moon, then we see what is known as a Supermoon. If a lunar apogee occurs very close to a full Moon then we see a Micromoon.
Moon Phase Calculator
Why does the Moon have phases?
At the new Moon phase, the Moon is so close to the Sun in the sky that none of the side facing Earth is illuminated (position 1 in illustration). In other words, the Moon is between Earth and Sun. At first quarter, the half-lit Moon is highest in the sky at sunset, then sets about six hours later (3). At full Moon, the Moon is behind Earth in space with respect to the Sun. As the Sun sets, the Moon rises with the side that faces Earth fully exposed to sunlight (5). The Moon has phases because it orbits Earth, which causes the portion we see illuminated to change. The Moon takes 27.3 days to orbit Earth, but the lunar phase cycle (from new Moon to new Moon) is 29.5 days. The Moon spends the extra 2.2 days «catching up» because Earth travels about 45 million miles around the Sun during the time the Moon completes one orbit around Earth.
At the new Moon phase, the Moon is so close to the Sun in the sky that none of the side facing Earth is illuminated (position 1 in illustration). In other words, the Moon is between Earth and Sun. At first quarter, the half-lit Moon is highest in the sky at sunset, then sets about six hours later (3). At full Moon, the Moon is behind Earth in space with respect to the Sun. As the Sun sets, the Moon rises with the side that faces Earth fully exposed to sunlight (5).
You can create a mockup of the relationship between Sun, Earth, and Moon using a bright lamp, a basketball, and a baseball. Mark a spot on the basketball, which represents you as an observer on Earth, then play with various alignments of Earth and Moon in the light of your imaginary Sun.
When is the Harvest Moon?
The full Moon that occurs closest to the autumnal equinox is commonly referred to as the «Harvest Moon,» since its bright presence in the night sky allows farmers to work longer into the fall night, reaping the rewards of their spring and summer labors. Because the equinox always falls in late September, it is generally a full Moon in September which is given this name, although in some years the full Moon of early October earns the «harvest» designation.
In fact, each full Moon of the year has its own name, most of which are associated with the weather or agriculture. The most common names used in North America include:
What is a Blue Moon and when is the next one?
Because the time between two full Moons doesn’t quite equal a whole month, approximately every three years there are two full Moons in one calendar month. Over the past few decades, the second full Moon has come to be known as a «blue Moon.» The next time two full Moons occur in the same month (as seen from the United States) will be July 2015. The most recent «blue Moon» occurred in August 2012.
On average, there’s a Blue Moon about every 33 months. Blue Moons are rare because the Moon is full every 29 and a half days, so the timing has to be just right to squeeze two full Moons into a calendar month. The timing has to be really precise to fit two Blue Moons into a single year. It can only happen on either side of February, whose 28-day span is short enough time span to have NO full Moons during the month.
The term «blue Moon» has not always been used this way, however. While the exact origin of the phrase remains unclear, it does in fact refer to a rare blue coloring of the Moon caused by high-altitude dust particles. Most sources credit this unusual event, occurring only «once in a blue moon,» as the true progenitor of the colorful phrase.
Why do we always see the same side of the Moon from Earth?
The Moon always shows us the same face because Earth’s gravity has slowed down the Moon’s rotational speed. The Moon takes as much time to rotate once on its axis as it takes to complete one orbit of Earth. (Both are about 27.3 Earth days.) In other words, the Moon rotates enough each day to compensate for the angle it sweeps out in its orbit around Earth.
When does the young Moon first become visible in the evening sky?
There is no real formula for determining the visibility of the young Moon. It depends on several factors: the angle of the ecliptic (the Moon’s path across the sky) with respect to the horizon, the clarity of the sky (how much dust and pollution gunks it up), and even the keenness of the observer’s eyesight.
The young Moon becomes visible to the unaided eye much earlier at times when the ecliptic is perpendicular to the horizon, and the Moon pops straight up into the sky. In these cases, it may be possible to see the Moon as little as 24 hours after it was new, although every hour beyond that greatly increases the chances of spotting it. When the ecliptic is at a low angle to the horizon, and the Moon moves almost parallel to the horizon as it rises, the Moon probably doesn’t become visible until at least 36 hours past new.
The record for the earliest claimed sighting of the young crescent Moon is around 19 hours, although most experts are suspicious of any claims of times less than about 24 hours.
Full Moon Calendar
When is the Next Full Moon?
The September full Moon, the Full Harvest Moon, will occur on Saturday, September 10, 2022.
Our 2022 Full Moon Calendar shows the date, time, and name of every full Moon this year, with information customized to your location and time zone!
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Full Moon Names
Historically, Native American and other traditional names for full or new Moons were used to track the seasons. The Moon names that we use in The Old Farmer’s Almanac come from Native American, Colonial American, or other traditional North American sources passed down through generations.
Note that for Native American names, each Moon name was typically applied to the entire lunar month in which it occurred, the month starting either with the new Moon or full Moon. Additionally, a name for the lunar month might vary each year or between bands or other groups within the same nation.
Some names listed here may reflect usage at one time in history, but may no longer be used by a designated group today. Many of the names listed here are English interpretations of the words used in Native American languages. They are only roughly aligned here with the months of the Gregorian calendar.
January – Wolf Moon
The howling of wolves was often heard at this time of year. It was traditionally thought that wolves howled due to hunger, but we now know that wolves use howls to define territory, locate pack members, reinforce social bonds, and gather for hunting. It is possible that European settlers may have used the term “Wolf Moon” even before they came to North America.
Another name for this time period was the Center Moon, from the Assiniboine people, because it was the middle of the winter season.
The Cree names of Cold Moon and Frost Exploding Moon refer to the frigid temperatures of this season, as does the Algonquin name of Freeze Up Moon. The Dakota names of Severe Moon and Hard Moon refer to the extreme cold and hard times of this season, as well as the fact that the snow sometimes develops a hard crust.
Other names for this time include Canada Goose Moon (Tlingit), Great Moon (Cree), Greetings Moon (Western Abenaki), and Spirit Moon (Ojibwe).
February – Snow Moon
In the 1760s, Captain Jonathan Carver, who had visited the Naudowessie (Dakota) and others, wrote that the name used for this period was the Snow Moon, “because more snow commonly falls during this month than any other in the winter.”
The Cree called this the Bald Eagle Moon or Eagle Moon. Bear Moon (Ojibwe) and Black Bear Moon (Tlingit) refer to the time when bear cubs are born. The Dakota called this the Raccoon Moon, and certain Algonquin peoples named it the Groundhog Moon. The Haida named it Goose Moon.
The Cherokee names of “Month of the Bony Moon” and “Hungry Moon” give evidence to the fact that food was hard to come by at this time.
March – Worm Moon
This name is traditionally thought to refer to the earthworms that appear as the soil warms in spring. Alternatively, during his travels in the 1760s, Captain Jonathan Carver wrote that this Moon name refers to a different sort of “worm”—larvae—which emerge from the bark of trees and other winter hideouts.
Although some Cree groups used the term Eagle Moon to describe the time around February, others used this term for the Moon cycle closer to spring. The Northern Ojibwe called this Crow Comes Back Moon. The term Goose Moon was used among Algonquin and Cree peoples. Snow Crust Moon was an Anishinaabe term. Sore Eyes Moon is a Dakota, Lakota, and Assiniboine term referring to the blinding rays of the sun on snow. Sugar Moon (Ojibwe) is the time when maple sap runs. Wind Strong Moon (Pueblo) refers to the strong windy days that come at this time of year.
April – Pink Moon
This Moon heralded the appearance of the “moss pink” (Phlox subulata), also called wild ground phlox or creeping phlox—one of the first spring wildflowers.
With spring thaws come the Algonquin Breaking Ice Moon and the Dakota Moon When the Streams are Again Navigable. When spring growth appears, so does the Budding Moon of Plants and Shrubs (Tlingit) and Moon of the Red Grass Appearing (Oglala). Animals returning to the area inspired the Lakota name Moon When the Ducks Come Back. Certain Dakota peoples chose the name Moon When the Geese Lay Eggs. Other names are Broken Snowshoe Moon (Anishinaabe), Frog Moon (Cree), and Sugar Maker Moon (Western Abenaki).
Appearing either in April or May, Sucker Moon (Anishinaabe) refers to a time to harvest sucker fish, which return to streams or lake shallows to spawn. According to legend, now is the time when this fish comes back from the spirit world to purify bodies of water and the creatures living in them. (This name may also be applied to the February Moon, to honor the sacrifice of the sucker fish in order to feed the Anishinaabe peoples, helping them to survive the winter.)
May – Flower Moon
The appearance of flowers in abundance inspired the name for this Moon, a term used by Algonquin and Ojibwe peoples.
Similarly, the Cree names of Budding Moon and Leaf Budding Moon celebrate the awakening of plant life. Egg Laying Moon and Frog Moon are other Cree terms for this period. Moon of the Shedding Ponies is an Oglala term. Planting Moon (Dakota, Lakota) marks the time to plant seeds and start the year’s crops.
June – Strawberry Moon
Used by the Algonquin, Ojibwe, Dakota, and Lakota peoples, among others, this name came about because ripe strawberries were ready to be gathered at this time.
Similarly, Berries Ripen Moon is a Haida term. Blooming Moon (Anishinaabe) is indicative of the flowering season. The time for tending crops is indicated by Green Corn Moon (Cherokee) and Hoer Moon (Western Abenaki).
Eighteenth-century Captain Jonathan Carver wrote that Native Americans whom he had visited used the term Hot Moon.
The Tlingit used the term Birth Moon, referring to the time when certain animals are born in their region. Egg Laying Moon and Hatching Moon are Cree terms for this period.
July – Buck Moon
At this time, the antlers of bucks (male deer) are in full growth mode. This Native American name was noted by Captain Jonathan Carver during his travels in the 1760s.
Other animal-related names include Feather Moulting Moon (Cree) and Salmon Moon, a Tlingit term indicating when fish returned to the area and were harvested.
As far as the plant world, there was Berry Moon (Anishinaabe), Moon When the Chokecherries are Ripe (Dakota), Month of the Ripe Corn Moon (Cherokee), and Raspberry Moon (Algonquin, Ojibwe), among others.
Thunder Moon (Western Abenaki) and Halfway Summer Moon (Anishinaabe) are other variants.
August – Sturgeon Moon
Lake sturgeon, found in the Great Lakes and Lake Champlain, as well as in several rivers, were once much more abundant. These large (some more than 6 feet long!) migratory fish were an important staple for Native American peoples living in the area. Captain Jonathan Carver came across this term for the lunar month during his travels in the 1760s.
Flying Up Moon is a Cree term describing the time when young birds are ready to fly.
Corn Moon (Algonquin, Ojibwe), Harvest Moon (Dakota), and Ricing Moon (Anishinaabe) signify the time to gather mature crops. The Assiniboine people named this period Black Cherries Moon, referring to when chokecherries were ripe.
The Tlingit called this time of season the Mountain Shadows Moon.
September – Corn Moon
Corn was ready to harvest at this time. In the 1760s, Captain Jonathan Carver came across this Native American term during his travels. Similarly, the Western Abenaki called this the Corn Maker Moon, and the Dakota, the Corn Harvest Moon.
Harvest Moon refers to the full Moon closest to the September equinox, which is the tradition that The Old Farmer’s Almanac follows. Read more about the Harvest Moon here.
Moon When Rice is Laid Up to Dry (Dakota) refers to the time of harvesting and processing rice.
Autumn Moon (Cree), Falling Leaves Moon (Ojibwe), Leaves Turning Moon (Anishinaabe), Moon of Brown Leaves (Lakota), and Yellow Leaf Moon (Assiniboine) all speak to the leaf-changing season.
Child Moon (Tlingit) occrus when young animals are weaned. Mating Moon and Rutting Moon are Cree terms that describe the time when certain animals, such as moose, are ready to mate.
October – Hunter’s Moon
This is the month when game is fattening up for winter. Now is the time for hunting and laying in a store of provisions for the long months ahead.
Drying Rice Moon (Dakota) describes the next process in preparing rice for winter. Falling Leaves Moon is an Anishinaabe term. Freezing Moon (Ojibwe) and Ice Moon (Haida) refer to the increasingly cold temperatures of this period. Migrating Moon (Cree) refers to the time when birds begin to fly south.
November – Beaver Moon
This was the time when beavers finished preparations for winter and retreated into their lodges. In the 1760s, Captain Jonathan Carver heard this Native American term during his travels.
Also in the realm of animals, Deer Rutting Moon (Dakota, Lakota) refers to the mating season. Digging/Scratching Moon is a Tlingit term for when bears dig their winter dens. Whitefish Moon (Algonquin) describes the spawning time for this fish.
As cold temperatures deepen, the terms Frost Moon (Cree, Assiniboine) and Freezing Moon (Anishinaabe) were also used.
December – Cold Moon
A name used by the Mohawk people, this Moon occurs when winter cold fastens its grip.
Other names that allude to the cold and snow include Drift Clearing Moon (Cree), Frost Exploding Trees Moon (Cree), Moon of the Popping Trees (Oglala), Hoar Frost Moon (Cree), Snow Moon (Haida, Cherokee), and Winter Maker Moon (Western Abenaki).
Long Night Moon is a Mohican term; Mid-Winter Moon, Lakota and Northern Ojibwe.
Other names include Moon When the Deer Shed Their [Antlers] (Dakota) and Little Spirit Moon (Anishinaabe).
Moon Phase Calendar for 2022
Today’s Moon is 75% of Full and 19 days old.
What’s the Moon’s phase today? With our 2022 Moon Phase Calendar, you’ll find when the next new Moon, first quarter, full Moon, or last quarter is happening—for all 12 months of 2022—customized to YOUR zip code. No manual converting to your local time! We also provide daily Moon illumination percentages and the Moon’s current age.
See Moon phases for all 12 months of 2022—plus, you can go backwards or forwards in time to find out the Moon’s phase on any date in the past or future.
Related links:
Moon Phase Calendar for August 2022 for Dublin, NH
First Quarter
7:07 A.M.
Full Moon
9:36 P.M.
Last Quarter
12:36 A.M.
New Moon
4:16 A.M.
| Moon Phase | Date | Time of Day |
|---|---|---|
| First Quarter | August 5 | 7:07 A.M. |
| Full Moon | August 11 | 9:36 P.M. |
| Last Quarter | August 19 | 12:36 A.M. |
| New Moon | August 27 | 4:16 A.M. |
All times in Eastern time.
About the Moon’s Phases
What Are Moon Phases?
As the Moon orbits around Earth and Earth orbits around the Sun, the angle between the Sun, Moon, and Earth changes. As a result, the amount of sunlight that reflects off the Moon and travels to our eyes changes every day. (The Moon itself produces no light of its own.)
We see the Moon’s disk change from all dark to all light to all dark again: This span of time is called a lunar cycle, lunation, lunar month, or synodic month. The length of the cycle can vary slightly, but on average, it is 29.53059 days. (See “What’s the Moon’s Age?” below for more information.)
Astronomers have broken down this cycle into four primary Moon phases: New Moon, First Quarter, Full Moon, and Last Quarter. There are also four secondary phases: Waxing Crescent, Waxing Gibbous, Waning Gibbous, and Waning Crescent. The primary phases occur at a specific moment, no matter where you are on Earth, which is then converted to local time. (Depending on where you live, you may or may not be able to see the exact moment of a phase, in part because the Moon may not have risen yet in your area.) The secondary phases, however, represent a span of time rather than a specific moment.
• New Moon
This phase is named as such because it starts a new lunar cycle. At this time, the Sun and Moon are in conjunction, meaning that they are closest together in the sky, on the same side of Earth (Sun→Moon→Earth). From our perspective, the Moon appears totally dark: We can not usually see it because we are facing the Moon’s shadowed side, which does not receive any direct sunlight. But if we were to travel to the other side of the Moon, the part that faces the Sun, it would be totally illuminated.
Occasionally, if the new Moon’s position lines up correctly between the Sun and Earth, from our viewpoint it will cover part or all of the Sun’s disk, causing a solar eclipse. These events are only visible from a small portion of Earth and require special eye protection to be viewed safely. (Read more about solar eclipses here!)
The months of some calendars, such as the Chinese lunisolar calendar, begin at the time of the new (or dark) Moon.
• Waxing Crescent
This phase occurs between the new Moon and first quarter phases. At the beginning of this stage, we see a thin, crescent-shape Moon, which, in the Northern Hemisphere, appears on the right side. The lit area slowly widens each day, covering more and more of the right side of the Moon’s surface until the first quarter phase, when the Moon’s entire right side is illuminated. (In the Southern Hemisphere, the same thing happens, only on the left side.)
Some lunar and lunisolar calendars, such as the Islamic (or Hijri) calendar, define the start of a month as when the Moon first becomes visible, which is usually a day or so after the new Moon, during its waxing crescent stage.
• First Quarter
This phase got its name because at this point the Moon has traveled 1/4 of the way through its orbit. It’s a confusing label, though, because at this time from our perspective, 1/2 of the Moon’s surface is lit. In fact, both the first and last quarter phases are sometimes called a Half Moon. At first quarter in the Northern Hemisphere, the right side of the Moon is illuminated; in the Southern Hemisphere, it’s the left side. In actuality, we are seeing 1/2 of the lit side of the Moon because the entire illuminated surface is only partly facing our direction. In other words, the Moon is perpendicular to the Earth/Sun line. During a first quarter phase, the Moon is said to be at east quadrature, meaning that it is 90 degrees east of the Sun when viewed from Earth.
• Waxing Gibbous
This phase occurs between the first quarter and full Moon and describes the Moon when it is more than half lit, but not yet fully. At the beginning of this stage in the Northern Hemisphere, we see the right half of the Moon illuminated plus a tiny fraction more extending into the left side. As the days pass, the light creeps farther left, covering more and more of the Moon’s surface until the full Moon phase, when the entire disk is illuminated. In the Southern Hemisphere, the same happens, only from left to right.
“Gibbous” comes from a Latin word meaning “humpbacked,” referring to the curved lit area on the Moon’s surface.
• Full Moon
This phase is named as such because, from our perspective, the full disk is illuminated. At this time, the Sun and Moon are in opposition, meaning that they are farthest apart in the sky, on opposite sides of Earth (Sun→Earth→Moon).
Occasionally, if the full Moon’s position lines up correctly with the Sun and Earth, from our viewpoint, the Moon will enter Earth’s shadow, which will cut off part or all of the sunlight reflected off the Moon’s surface, thereby causing a lunar eclipse. (Learn more about lunar eclipses here!)
• Waning Gibbous
This phase occurs between the full and last quarter and describes the Moon when it is more than half lit, but not fully. At the beginning of this stage in the Northern Hemisphere, we see a disk almost fully lit except for a tiny sliver on the right side that is in darkness. As the days pass, the lit area shrinks from right to left until the last quarter phase, when the Moon’s left half is illuminated and the right half is in darkness. In the Southern Hemisphere, the same happens, only the light shrinks from left to right.
• Last Quarter
This phase got its name because at this point the Moon has traveled 3/4 of the way through its orbit, and has just one more (the last) quarter to complete one revolution. This stage is sometimes also called Third Quarter. At this stage, we see 1/2 of the Moon’s surface lit. In the Northern Hemisphere, the left side is illuminated; in the Southern Hemisphere, it is the right side. During a last quarter phase, the Moon is said to be at west quadrature, meaning that it is 90 degrees west of the Sun when viewed from Earth.
• Waning Crescent
This phase occurs between the last quarter and new Moon phases. At the beginning of this stage, in the Northern Hemisphere, we see the Moon’s entire left side almost fully lit and the right side in darkness. The lit area slowly shrinks each day, covering less and less of the Moon’s surface until it looks like a very thin crescent on the left side. Eventually, the entire disk will be in darkness, at which point it will be the new Moon phase and another lunar cycle will have begun. (In the Southern Hemisphere, the same thing happens, only the lit area would have started on the right side and shrunk from left to right, until a thin crescent remained on the right.) Once the Sun rises, it is not easy to see this slim phase; the best time is before the glare of sunrise.
What Is the Moon’s Age?
The term «Moon’s age» is not a reference to how long the Moon has existed (about 4.5 billion years, if you’re wondering), but rather how many days it’s been since the last new Moon. As mentioned above, the span of time between one new Moon and the next is called a lunar cycle, lunation, lunar month, or synodic month and on average lasts for 29.53059 days. This translates to 29 days, 12 hours, 44 minutes, and 3 seconds.
For most dates in the above Moon Phase Calendar, there is listed at the bottom of the grid cell a number of days, such as “18 days.” This tells us the amount of days since the previous new Moon, or in other words, how many days into the lunar cycle we are—aka, the Moon’s age. So, at the new Moon, that day is “0” (not labeled); the next day, 1 day has passed; and onward until 29 days pass and we are at the next new Moon. You can also find this information in the print edition of The Old Farmer’s Almanac, in the last (right) column of the Left-Hand Calendar Pages.
The length of a lunar cycle can vary by more than 13 hours due to a few factors. For example, when the new Moon phase occurs at about the same the time as perigee (the point in the Moon’s elliptical orbit that is closest to Earth), shorter lunations result. When the new Moon phase occurs at about the same time as apogee (when the Moon is farthest from Earth), longer lunations result. This is related to the fact that the Moon travels faster in its orbit at perigee and slowest in its orbit at apogee.
Earth’s relative position near perihelion (point in Earth’s orbit that is closest to the Sun) and aphelion (when Earth is farthest from the Sun) also affect lunation times. The longest lunations result when the new Moon coincides with apogee and Earth is at perihelion. The shortest lunations result when the new Moon coincides with perigee and Earth is at aphelion.
One of the shortest lunations was 29 days, 6 hours, and 35 minutes, whereas one of the longest was 29 days, 19 hours, 55 minutes.
Note: The synodic month describes the time for the Moon to complete one orbit around Earth and return to the same position relative to the Sun and Earth. If Earth were not moving along in its orbit but instead were standing still, the Moon would take less time to reach that same position: This is called the sidereal month, which is about 2.21 days shorter than the synodic month. “Sidereal” means “related to stars”—in this case, the Moon’s position relative to the stars.
What Is Percent Illumination?
Percent illumination, listed in the Moon Phase Calendar under the Moon symbol, tells us how much of the Moon’s disk is lit, as seen from Earth. Looking at the calendar on this page, you can see that from new to full, the percentage increases, indicating the waxing stages, and from full to new, the percentage decreases, indicating the waning stages. The New Moon is 0 percent illuminated (or totally dark); First Quarter is essentially 50 percent illuminated (half of the disk is lit); Full Moon is 100 percent illuminated (the entire disk is lit); and Last Quarter is back to essentially 50 percent illuminated (half of the disk is lit).
We say “essentially” for the quarter phases because technically, at the exact time of the first quarter, a tiny fraction more than half of the Moon is lit, and at last quarter, a tiny fraction less. The Moon is exactly half-lit when it reaches dichotomy, which occurs several minutes before first quarter and several minutes after last quarter.
When Does the Moon Rise and Set?
Below are general guidelines as to where to look for the Moon during each of its phases. Times mentioned are solar time, not clock time. The four primary phases (in italics) rise and set at a point in time; the four secondary phases occur over a broader timespan.
Moon Phase Rise and Set Times
What Is Earthshine?
Earthshine is sunlight that dimly illuminates the dark part of the Moon’s surface that faces us. It occurs when light travels from the Sun to Earth, reflects off the Earth, travels to the Moon, and then bounces back to Earth to reach our eyes. When this happens, we can see part of the Moon that normally isn’t lit, but this portion is much dimmer than section directly illuminated by sunlight.
For example, during a waxing crescent stage, we might see a thin crescent brightly lit by direct sunlight, but also the rest of the Moon’s disk slightly illuminated by a much dimmer glow from earthshine. Sometimes this appearance is called the “old Moon in the new Moon’s arms.”
Earthshine is most noticeable within five days of a new Moon (during the waning and waxing crescent stages).
Phase of the moon definition
Phase of the moon definition: (astronomy) the particular appearance of a body’s state of illumination (especially one of the recurring shapes of the part of Earth’s moon that is illuminated by the sun)
Each phase of the moon has its own name, and definition to go along with it. There’s Waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, waxing crescent, and then the new moon.
Waxing phase of the moon definition:
Waxing refers to the phases between the new moon and the full moon, this technically includes the first quarter, but more in spirit than technicalities. When not talking about wax the substance, “Wax” means to grow. It’s a word that gets its roots in both the Old English, Dutch and Germanic dialects, the Old English word was “Weaxan, Dutch “Wassen” and German “Wachsen”. Which are all derived from the Greek “Auxanein” and the Latin “Augere” which both mean “to increase.”
The full moon has a very straightforward moon phase definition, in that the moon’s face is fully apparent to us.
Waning phase of the moon definition
Waning is after the full moon, when it begins to diminish and edge towards the new moon phase. It comes from the old English word Wanian, which means to lessen. Also means to “decline” and “diminish”. In a more literary sense, when applied to a more literary sense it’s to become weak.
The New moon phase gets its name because that’s when a lunar month has been said to begin. The apparent absence of the moon leads to the idea that the moon had gone and would become new again to repeat the cycle.
Gibbous phase of the moon definition:
Gibbous is to be convex on both sides, so when the moon is more than half-full it’s considered to be gibbous. It also means “humpbacked” or “bulging”. It comes from the Latin word “gibbous” which simply means “humped”.
Crescent phase of the moon definition:
Crescent is defined as a shape like the segment of a ring, which tapers to points at both ends. It an Anglo-French variance of the Latin Crescent and Crascens.
The history and the calendar
The lunar calendar takes 12 of the moon phase cycles and uses that to define a year. Although that calendar is actually off by about 10 to 11 days from the solar calendar that we use today, which is much more accurate.
Certain cultures and religions still use the lunar calendar to determine their holidays. Chinese uses it to determine their new year’s celebrations, and to help determine their zodiac. And the religion of Islam uses it to determine their holy days.
Using the moon as a calendar gave way to different cultures naming different full moon phases as their way of marking their month. Most of the lasting full phase of the moon definitions and names were from different Native American cultures, and Anglo-Saxon/Celtic cultures. January’s full moon name, for example, is most often called the “wolf moon” for the way the wolves would congregate and behave during this time.
Phases of the Moon Definitions that Always work with Moonglow Jewelry
While every phase has the technical definition, the best definitions come from your own heart. Every memory becomes a phase of the moon definition with custom moon jewelry that glows at night. Plug in any date and the custom moon phase calendar will be able to calculate what the phase of the moon was on that date and print it onto the beautiful and custom pieces of jewelry that is great for you, or a friend and relatives.
Let your special memory become the definition for every phase of the moon in the sky. Check out Moonglow’s custom necklaces, bracelets, rings, and earrings for both men and women on their website here.