There were some variations in these moon names, but in general, the same ones were used by the Algonquin tribes from New England to Lake Superior. European settlers who arrived in those areas followed their own customs and created some of their own names. Because the lunar ("synodic") month is roughly 29.5 days long on average, the dates of these full moons shift from year to year. [The Moon: 10 Surprising Lunar Facts]
Here is a listing of all of the full moon names, as well as their dates and times for 2018. Unless otherwise noted, all times are for the Eastern time zone.
Jan. 1: TheFull Wolf Moon
Amid the bitter cold and deep snows of midwinter, the wolf packs howled hungrily outside Native American villages. It was also known as the Old Moon or the Moon After Yule. Some tribes called it the Full Snow Moon.
The moon reaches fullness at 9:24 p.m. EST and will arrive at perigee (its closest point to Earth in its orbit) about 4.5 hours earlier, at 5:00 p.m. EST, at a distance of 221,559 miles (356,565 kilometers) from Earth. (A full moon that takes place during perigee is sometimes known as a supermoon.) Because the full moon coincides with perigee, it will appear to be the biggest full moon of 2018. In addition, very high ocean tides can be expected during the two or three days after peak fullness.
Jan. 31: The Full Snow Moon
Usually this title is reserved for a full moon in February, since world tends to be fully coated in snow by then. But this year is an oddity, in that there will be no full moon in February. (This is true for most locations on Earth, but in some places, including eastern Asia and eastern Australia, the moment of peak fullness will occur on the morning of Feb. 1.) During February, the snow and bitter cold makes hunting difficult, so some tribes called this moon the Full Hunger Moon.
This is the second time the moon turns full in a calendar month, so it is also popularly known as a Blue Moon. On average, full moons occur every 29.53 days (the length of the synodic month), or 12.37 times per year. So months containing two full moons occur, on average, every 2.72 years. This year, however, is a striking exception to this rule, as you will soon see.
Jan. 31 will also be the night of atotal lunar eclipse.The Pacific Rim — the lands around the rim of the Pacific Ocean— will have a ringside seat for this event: Totality will last 77 minutes, and at mideclipse, the moon will appear directly overhead (or nearly so) over the open waters of the western Pacific Ocean.
In the western U.S. and western Canada, the eclipse will take place during the predawn hours, but across the rest of North America, the progress of the eclipse will be interrupted by moonset.
February: No full moon.
This occurrence happens once every 19 years. The last time February didn't have a full moon was in 1999, and the time before that was 1980; the next time there will be no full moon in February will be 2037. (Once again, this is true for most locations on Earth, but in some places, including eastern Asia and eastern Australia, the moment of peak fullness will occur on the morning of Feb. 1.)
The timing of the full moon is related to the Metonic Cycle, which is named for the Greek astronomer Meton, who discovered this phenomenon around 500 B.C. He noted that a given phase of the moon usually falls on the same date at intervals of 19 years. There doesn't seem to be a name for a month that lacks a full moon, but February is the only month in which this can happen. Recall what we noted above: The lunar ("synodic") cycle is roughly 29.5 days on average, but even during leap years, February cannot have more than 29 days. So if a full moon takes place on the final day of January, the next full moon will jump over February and occur at the beginning of March. And this will result in a second month with two full moons; the second full moon makes up for the lack of a full moon in February.
March 1: The Full Worm Moon
In March, the ground softens, and the earthworm casts reappear, inviting the return of the robins. The 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. Fullness occurs at 7:51 p.m. EST(0051 GMT on March 2).
March 31: The Full Sap Moon
Marking the time of tapping maple trees, this is another variation of the Full Worm Moon. In 2018, this is also the Paschal Full Moon, or the first full moon of the spring season. The first Sunday following the Paschal Moon is Easter Sunday, which indeed will be observed the very next day, on Sunday, April 1. This is also the second Blue Moon of 2018 — once again, depending your location, because the moon reaches peak fullness on April 1 for some locations. Fullness occurs at 8:37 a.m. EDT (0037 GMT on April 1.)
April 29: The Full Pink Moon
One of the earliest-blooming, widespread flowers in North America is the grass pink or wild ground phlox. Other names for this full moon are the Full Sprouting Grass Moon, the Egg Moon and, to some coastal tribes, the Full Fish Moon, to mark when the shad come upstream to spawn. Fullness occurs at 8:58 p.m. EDT (0058 GMT on April 30).
May 29: The Full Flower Moon
By this time of year, flowers are abundant. The Full Flower Moon was also known as the Full Corn Planting Moon or the Milk Moon. Fullness occurs at 10:20 a.m. EDT (1420 GMT).
June 28: The Full Strawberry Moon
Strawberry-picking season peaks this month. Europeans called this the Rose Moon. Fullness occurs at 12:58 a.m. EDT (1658 GMT).
July 27: The Full Buck Moon
This full moon occursin the month 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, because it's when thunderstorms are the most frequent in this part of the world. Sometimes, it's also called the Full Hay Moon.
There will also be a total eclipse of the moon on July 27. However, it will not be visible in North America because it will be happening during the daytime, when the moon is below the horizon. Much of the Eastern Hemisphere — from Europe and Africa, eastward across Asia to Japan, Indonesia and much of Australasia — will be able to watch this rather exceptionally long totality, which will last 103 minutes. Because the moon arrives at apogee (its farthest point from Earth in its orbit) about 14 hours earlier, this will also be the smallestfull moon of 2018; it will appear 12.3 percent smaller than the full moon of Jan. 1. Fullness occurs at 4:20 p.m. EDT (2020 GMT); the eclipse will peak at 3:21 EDT (1921 GMT).
Aug. 26: The Full Sturgeon Moon
This full moon occurswhen this large fish of the Great Lakes and other major bodies of water, like Lake Champlain, are most readily caught. A few tribes knew it as the Full Red Moon, because when the moon rises, it looks reddish through the sultry summer haze. It is also known as the Green Corn Moon or the Grain Moon.Fullness occurs at 7:56 a.m. EDT (1156 GMT).
Sept. 24: The Full Harvest Moon
Traditionally, this designation goes to the full moon that occurs closest to the autumnal (fall) equinox. The Harvest Moon usually comes in September, but (on average) once or twice per decade, it will fall in early October. At the peak of the harvest, farmers can work into the night by the light of this moon. Usually, the 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 each night 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. Fullness occurs at 10:52 p.m. EDT (0252 GMT on Sept. 25).
Oct. 24: The Full Hunter's Moon
With the leaves falling and the deer fattened, it's now time to hunt. Because the fields have been reaped, hunters can ride over the stubble and more easily see foxes, as well as other animals, which can be caught for a banquet after the harvest. Fullness occurs at 12:45 p.m. EDT (1645 GMT).
Nov. 23: The Full Beaver Moon
At this point of the year, it's time to set beaver traps before the swamps freeze, to ensure a supply of warm winter furs. Another interpretation suggests that the name Full Beaver Moon comes from the fact that the beavers are now active in their preparation for winter. It's also called the Frosty Moon. Fullness occurs at 12:39 a.m. EST (0539 GMT).
Dec. 22: The Full Cold Moon
It's not hard to understand where the name of this moon comes from, as December is the month in which the winter cold fastens its grip on this part of the world. On occasion, this moon was also called the Moon Before Yule. Sometimes, this moon is referred to as the Full Long Nights Moon, which is appropriate because the winter solstice (the longest night of the year) occurs in December, and the moon is above the horizon for a long time. In December in the Northern Hemisphere, the full moon makes its highest arc across the sky because it's diametrically opposite to the low sun. In fact, the moment of the winter solstice comes just over 19 hours before this full moon, at 5:23 p.m. EST on Dec. 21. Peak fullness occurs at12:49 p.m. EST (1749 GMT).
Which of these lunar displays is your favorite skywatching treat?
Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmer's Almanac and other publications, and he is also an on-camera meteorologist for Verizon Fios1 News, based in Rye Brook, New York.