Full moon names date back to Native Americans, of what is now the northern and eastern United States.
Those tribes of a few hundred years ago kept track of the seasons by giving distinctive names to each recurring full moon. Their names were applied to the entire month in which each occurred.
To be sure, there were some variations in the moon names, but in general the same ones were current throughout the Algonquin tribes from New England on west to Lake Superior. European settlers followed their own customs and created some of their own names.
Since the lunar ("synodic") month is roughly 29.5 days in length on average, the dates of the full moon shift from year to year.
Here is a listing of all the full moon names, as well as the dates and times (for the Eastern time zone) for the next twelve months.
Jan. 6: Full Wolf Moon
Jan. 6 at 6:08 p.m. EST (2308 GMT)
Amid the zero cold and deep snows of midwinter, the wolf packs howled hungrily outside Indian villages. It was also known as the Old Moon or the Moon After Yule. In some tribes this was the Full Snow Moon; most applied that name to the next moon.
Feb. 5: Full Snow Moon
Feb. 5 at 1:29 p.m. EST (1829 GMT)
Usually, the heaviest snows fall in this month. Hunting becomes very difficult, and hence to some tribes this was the Full Hunger Moon.
March 7: Full Worm Moon
March 7 at 1:29 p.m. EST (1829 GMT)
In this month the ground softens and the earthworm casts reappear, inviting the return of the robins. The more northern tribes knew this as the Full Crow Moon, when the cawing of crows signals the end of winter, or the Full Crust Moon because the snow cover becomes crusted from thawing by day and freezing at night. The Full Sap Moon, marking the time of tapping maple trees, is another variation.
April 6: Full Pink Moon
April 6 at 12:35 a.m. EDT (0435 GMT)
The grass pink or wild ground phlox is one of the earliest widespread flowers of the spring. Other names were the Full Sprouting Grass Moon, the Egg Moon, and — among coastal tribes — the Full Fish Moon, when the shad came upstream to spawn. This is also the first full moon of spring — the so-called Paschal Moon. Ecclesiastical rules mandate that the first Sunday after this moon is Easter, and so it will be on the 9th.
May 5: Full Flower Moon
May 5 at 1:34 p.m. EDT (1734 GMT)
Flowers are abundant everywhere. It was also known as the Full Corn Planting Moon or the Milk Moon. or Antarctica, Oceania, Australasia, Asia, Europe, Africa, South Georgia and the South Sandwich Islands, a penumbral lunar eclipse also occurs on this night. Within an hour of either side of the moment of maximum eclipse (17:24 GMT in which nearly 97% of the moon will be inside the penumbral shadow) a subtle darkening may appear along the moon’s upper limb. But unfortunately, this eclipse is not visible from North America.
June 3: Full Strawberry Moon
June 3 at 11:42 p.m. EDT (0342 GMT on June 4)
Known to every Algonquin tribe. Europeans called it the Rose Moon. Strawberry picking season peaks during this month.
July 3: Full Buck Moon
July 3 at 7:39 a.m. EDT (1139 GMT)
The Full Buck Moon, when the new antlers of buck deer push out from their foreheads in coatings of velvety fur. It was also often called the Full Thunder Moon, thunderstorms being now most frequent. Sometimes also called the Full Hay Moon.
Aug. 1: Full Sturgeon Moon
Aug. 1 at 2:32 p.m. EDT (1832 GMT)
The Sturgeon Moon, when this large fish of the Great Lakes and other major bodies of water like Lake Champlain is most readily caught. A few tribes knew it as the Full Red Moon because the moon rises looking reddish through sultry haze, or the Green Corn Moon or Grain Moon.
Aug. 30: The Blue Moon
Aug. 30 at 9:36 p.m. EDT (0136 GMT)
The second full moon occurring within a calendar month is usually bestowed this title. Although the name suggests that to have two Full Moons in a single month is a rather rare occurrence (happening "just once in a . . . "), it actually occurs once about every three years on average.
There is actually a second and more arcane definition of a Blue Moon, apparently conceived by an almanac editor based in Maine back in the 1930s, but we will not get into this here. In addition, the moon will also be at perigee at 12:00 p.m. EDT., at a distance of 221,942 miles (357,181 km) from Earth. Very high tides can be expected from the coincidence of perigee with full moon (referred to as an astronomical spring tide). Finally, a full moon occurring very late in August or very early in September is sometimes bestowed with the title of Fruit Moon or Barley Moon. This will be the case with this second August full moon in 2023.
Sept. 29: Full Harvest Moon
Sept. 29 at 5:58 a.m. EDT (0958 GMT)
Traditionally, this designation goes to the full moon that occurs closest to the Autumnal (Fall) Equinox. In most years, the Harvest Moon comes in September, but about every four or five years it occurs in October (next time this will happen will be in 2025). At the peak of the harvest, farmers can work into the night by the light of this moon.
Usually, the full moon rises an average of 50 minutes later each night, but for the few nights around the Harvest Moon, the moon seems to rise at nearly the same time each night: just 25 to 30 minutes later across the U.S., and only 10 to 20 minutes later for much of Canada and Europe. Corn, pumpkins, squash, beans, and wild rice — the chief Native American staples — are now ready for gathering.
Oct. 28: Full Hunter's Moon
Oct. 28 at 4:24 p.m. EDT (2024 GMT)
With the leaves falling and the deer fattened, it is time to hunt. Since the fields have been reaped, hunters can ride over the stubble, and can more easily see the fox, also other animals that have come out to glean and can be caught for a Thanksgiving banquet after the harvest.
A partial lunar eclipse also occurs on this date. Unlike the May event, this one sees the moon brush the Earth's darker umbral shadow; at maximum (20:14 GMT) about 12% of the moon's diameter will be within the shadow, darkening its lower limb. The Earth's Eastern Hemisphere faces the moon when the eclipse takes place, however, Atlantic Canada will see the last of the umbra slip off the moon when it rises and sharp-eyed New Englanders will be able to perceive the faint shading of the penumbra as the moon appears above their horizon.
Nov. 27: Full Beaver Moon
Nov. 27 at 4:16 a.m. EST (0916 GMT)
Some accounts suggest the name Beaver Moon came from the fact that this moon signaled it was time to set beaver traps before the swamps freeze to ensure a supply of warm winter furs! Another interpretation suggests that the name Beaver Full Moon comes from the fact that the beavers are now active in their preparation for winter. Also called the Frosty Moon.
Dec. 26: Full Cold Moon
Dec. 26 at 7:33 p.m. EST (0033 GMT on Dec. 27)
The Full Cold Moon; among some tribes, the Full Long Nights Moon. In this month the winter cold fastens its grip, and the nights are at their longest and darkest. Also sometimes called the Moon before Yule (Yule is Christmas, and this time the moon is only just after it; the next full moon that falls on Christmas Day will come in 2034).
The term Long Night Moon is a doubly appropriate name because the midwinter night is indeed long and the moon is above the horizon a long time. The midwinter full moon takes a high trajectory across the sky because it is opposite to the low sun.
Lastly, here are some interesting calendrical facts that famed astronomical calculator Jean Meeus has compiled concerning the phases of the moon. All are cyclical, the most noteworthy being the so-called Metonic Cycle that was independently discovered by the Greek astronomer Meton (born about 460 B.C.). This is a 19-year cycle, after which time the phases of the moon are repeated on the same days of the year, or approximately so. For instance, there is a full moon on Aug. 1, 2023. Nineteen years hence, in 2042 there'll be another full moon on Aug. 1.
Another interesting cycle: after two years, the preceding lunar phase occurs on, or very nearly the same calendar date. Thus, in 2025, the First Quarter Moon will occur on Aug. 1. After eight years, the same lunar phases repeat, but occur one or two days later in the year. The Greeks called this eight-year cycle the octaeteris. Indeed, in 2031, a full moon occurs on Aug. 2.
Finally, in our Gregorian Calendar, 372 years provides an excellent long period cycle for the recurrence of a particular phase on a given date. Thus, we know with absolute certainty that the same full moon that shines down on us on Aug. 1 of 2023 will also be shining on Aug. 1 in the year 2395.
Mark your calendars!
Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmers' Almanac and other publications. Follow us on Twitter @Spacedotcom and on Facebook.