The Beaver Moon is November’s full moon, and in 2026 it is also a supermoon, which means two folk-naming habits land on the same night: one very old, one barely fifty years old.
The beaver’s moon
The name comes from the fur trade and the animal at once. November was the season to set beaver traps, while the pelts were thick for winter and before the swamps iced over and locked the lodges shut. It is also the month the beavers themselves work hardest, hauling mud and wood to finish their dams before the freeze. Trapper and beaver were racing the same cold, and the moon took both their names. The older European name for the same moon, the Frost Moon, simply marks what was coming.
What a supermoon actually is
The moon’s orbit is not a circle but an ellipse, so its distance from Earth changes through the month. When a full moon happens to fall near perigee, the closest point of that orbit, we get a supermoon: a full moon perhaps seven percent wider and a bit brighter than average. The effect is real but subtle, easy to measure and hard to notice by eye, especially since a moon low on the horizon always looks large for reasons of perception alone.
The word itself is young. An astrologer, Richard Nolle, coined “supermoon” in 1979; astronomers had always just called it a perigee full moon. The popular name won, the way these things do, and now every close full moon arrives with the label attached.
What we are really looking at
The Beaver Moon is the last full moon before winter shuts the year down, named for the scramble to be ready, by people and by beavers alike. The supermoon part is a slightly bigger disc and a very modern word. Underneath both is the same November moon that has watched the water freeze over for as long as there have been beavers to build against it.
Image: American Beaver, from John James Audubon’s “Viviparous Quadrupeds of North America” (1845). Public domain, via Wikimedia Commons.
Sources
Bibliography. The same list is held in the article’s frontmatter for the citation tools that read it programmatically.
- The Old Farmer’s Almanac, ‘Full Moon Names and Their Meanings’ (almanac.com)
- NASA, ‘What Is a Supermoon?’ (science.nasa.gov)
- Sky & Telescope, ‘Native American Full Moon Names’ and supermoon explainers (skyandtelescope.org)