Why is the moon bigger tonight? Name of December full moon explained; see pics
The second largest full moon of 2025 appears higher in the night sky than any other full moon throughout the year, this December 4.
Sky-watchers might be in for a surprise today as the full moon appears bigger and brighter than usual. It has already elicited reactions from many online.
“If the moon gets any bigger we're shooting it down with a damn missile,” a person quipped on X. Another asked, “Can anyone explain why the moon looks 2x bigger today.”
The reason is because the second largest full moon of 2025 appears higher in the night sky than any other full moon throughout the year, this December 4. It is called the Cold Supermoon. The moon was officially full as of 6:14 p.m. EST on Thursday.
What to know about the Cold Supermoon
The Cold Supermoon is the traditional name for the December full moon. At this time, the moon is also closest to earth, which is why it appears bigger. This Cold Supermoon rises within constellation Taurus.
Also Read | Full moon this week: When is December’s supermoon ‘Cold Moon’? List of 2026 full moons
The Cold Supermoon is most visually impressive at the time of moonrise. This is the third of four supermoons in a row and the second largest of the year after the Beaver Moon which comes in November. Supermoons are normally 10% larger than average.
The Cold Moon also promises to look impressive on December 5, when it rises an hour or so after sunset. Indigenous people of the US had their own names for the December full moon. They reportedly called it Frost Exploding Trees Moon (Cree), the Moon of the Popping Trees (Oglala), the Moon When the Deer Shed Their Antlers (Dakota), the Winter Maker Moon (Western Abenaki), the Cold Moon (Mohawk) and the Long Night Moon (Mohican).
Visuals of Cold Supermoon
Several sky-watchers and NASA put out photos of the Cold Supermoon. “Look up at the Moon! The last full moon of 2025 reaches its peak on Thursday, Dec. 4. This month's full moon is also a supermoon—meaning that it will appear slightly bigger and brighter than usual,” NASA posted.
Another page noted “Tonight's full cold Moon. the last supermoon of the year!.”
Yet another person shared photos and made a 2025 also nears an end.
“Yes yes yes — the last Supermoon of the year! I release everything that no longer serves me and welcome the new adventures rising on my path. I am ready, aligned, and open to all the magic coming my way,” the person wrote.
