Winter is coming to the Northern Hemisphere, and the heavens have quite a spectacle planned for the occasion.
On Dec. 21, the arrival of the winter solstice, the moon will form a conjunction with the bright star Aldebaran—with the two celestial bodies meeting and passing each other—on the same night as the year’s only Ursid meteor shower. The following night, the “full cold moon” will rise in the skies. A heavenly event quite like this won’t happen again until 2094, which is the next time the last full moon of the year coincides with the official start of the cold season.
Indeed, the full cold moon gets its name because of the weather. The Farmer’s Almanac referred to the last full moon of the year by this name because that’s what some Native Americans called it, given winter came with it. But around the world and over time, the occurrence has had a plethora of names, many of them very descriptive.
According to NASA, the last full moon of the year, when it coincides with the winter solstice, was also called the Long Night Moon by some Native Americans, as it occurred on the longest night of the year. The full moon at this time takes a high trajectory across the sky because it is opposite to the low sun, so the moon will be above the horizon longer than at other times of the year, NASA explains.
In the Pacific Northwest, the Haida tribe called December’s full moon the snow moon, or Ta’aaw Kungaay. The Tlingit of Alaska called it Shanáx Dís, meaning “unborn seals are getting hair,” according to the Tlingit Moon and Tide Teaching Resource. And the Hopi, who lived mostly in what’s now known as Arizona, called this the Sparrow-Hawk moon, the Journal of Mathematical Culture (pdf) reports.
The Ojibwe people from the region now known as Ontario, Canada called it Mnidoons Giizis, meaning the big spirit moon or blue moon. “Its purpose is to purify us, and to heal all of Creation,” according to the Ontario Native Literacy Coalition (pdf, p. 11), which teaches First Nation languages. The same text explains that the Cree people referred to December’s full moon as Thithikopiwipisim, meaning the hoar frost moon of the “month when frost sticks to leaves and other things outside.”
In China’s traditional lunar calendar, the December lunation is called Dōngyuè, meaning “winter month,” and it marked the seasonal solstice. In Europe, the celestial event was historically called the “moon before Yule,” a reference to an old northern European winter festival that’s now associated with Christmas.
Meanwhile, in the Southern Hemisphere, where December is a summer month, the Māori people of New Zealand called the lunation Hakihea, meaning “birds are now sitting in their nests.“
Whatever you call this year’s very special full cold moon, do look skyward and reflect on this distant friend who influences our lives and has for all of time. “As we look at the moon on such an occasion, it’s worth remembering that the moon is more than just a celestial neighbor,” John Keller of NASA’s Goddard Space Flight Center in Greenbelt, Maryland said in 2015, when the full moon came at Christmas. “The geologic history of the moon and Earth are intimately tied together such that the Earth would be a dramatically different planet without the moon.”