This week, sky watchers will be treated to the last full moon of the year. The Wolf Moon will become officially full late Tuesday night, but will continue to look like a full moon through Thursday.
This is actually the 13th full moon of the year. Wait, what? Twelve months and 13 full moons – that’s so 2020. October’s lunar cycle pushed us toward this, with two full moons that month, one rising on Oct. 1 and the other on Halloween.
This week’s full moon has many names, but seasonally it’s best known as the Wolf Moon, Gordon Johnston explains in his recent NASA blog.
“By season, as the first full Moon of winter, the Algonquin tribes of what is now the northern and eastern United States named this the Wolf Moon, from the packs of wolves that howled hungrily outside the villages amid the cold and deep snows of winter,” he said.
Other names for it include the Ice Moon, the Old Moon or, seasonally, the Moon After Yule.
“Europeans called this the Moon after Yule, a three-day winter solstice festival in pre-Christian Europe. In the 10th century, King Haakon I associated Yule with Christmas as part of the Christianization of Norway, and this association has spread throughout the countries that follow European traditions.”
Because it’s the full moon closest to our recent Winter Solstice on Dec. 21, this week’s moon is also known as the Long Night Moon, marking the time of year when we have our shortest days and our longest and darkest nights.
“The moon will be in the sky for a total of 15 hours 27 minutes, with 14 hours 31 minutes of this when the sun is down, making Tuesday evening into Wednesday morning, Dec. 29 to 30, 2020, the longest full Moon night of the year,” he said.
In his blog, Johnston does his calculations from NASA’s Washington D.C. office, but it’s roughly the same for Michigan.
This week’s full moon is also the last full moon of the decade. Think we closed out the decade in 2019? Calendar purists say no, that this New Year’s Eve is the final party for the decade and Jan. 1, 2021, marks the beginning of the next decade, according to EarthSky.
“Although it’s somewhat arbitrary, most people regarded the full moon of Dec. 12, 2019, as the last full moon of the decade (2010 to 2019). Purists insist, however, that the full moon of Dec. 30, 2020, counts as the last full moon of the decade, and that 2020 – not 2019 – ends the second decade of the 21st century (2001 to 2100).”