Witness Earth’s Closest Lunar Encounter of the Year
Your Guide to the Celestial Event
Witness a celestial spectacle this December as the highly anticipated supermoon in December 2025 graces the skies over the USA. Get ready to gaze upon the “Cold Moon,” an astronomical event that promises to be a stunning visual treat for skywatchers across the nation. This isn’t just any full moon; it’s a supermoon, meaning our lunar companion will appear noticeably larger and brighter than usual. Join us as we delve into what makes this particular Full Moon on December 4, 2025, so special, when and where to catch its peak illumination, and tips for the ultimate viewing experience. Prepare to mark your calendars for the grand finale of 2025’s supermoon series!
Understanding the Supermoon Phenomenon
What exactly makes a moon “super”? The term supermoon refers to a Full Moon (or New Moon, though not visible) that occurs when the Moon is at or very near its perigee, which is the point in its elliptical orbit when it is closest to Earth. This proximity makes the Moon appear larger and more brilliant in our night sky. Conversely, when the Moon is farthest from Earth, at its apogee, it’s sometimes referred to as a “micromoon.” While the difference might be subtle to the casual observer, a supermoon can appear up to 14% larger in diameter and 30% brighter compared to a micromoon. This December, we’re in for one of these magnificent close encounters.
The December 2025 Cold Moon: Key Details
The supermoon in December 2025 is traditionally known as the “Cold Moon,” a name originating from Native American traditions that mark the onset of winter’s deep cold. This particular Cold Moon holds extra significance as it will be the last supermoon of 2025, and the third in a captivating series of four supermoons extending into early 2026.
The Moon will reach its peak illumination at precisely 6:14 p.m. Eastern Time (ET) on Thursday, December 4, 2025. For those eager to witness this celestial event, the good news is that the Moon will appear full from December 3rd to December 5th, offering multiple opportunities for observation. This highest full moon of 2025 will shine majestically, appearing approximately 7.9% larger and 15% brighter than an average Full Moon.
Optimal Viewing Experience Across the USA
For the most dramatic experience of this supermoon, skywatchers across the U.S. are highly encouraged to observe it just after moonrise on December 4th, especially as it ascends over the eastern horizon at sunset. This is when the famous “Moon illusion” comes into play, making the Moon appear even more colossal when viewed near the horizon against foreground objects like trees or buildings.
To ensure optimal viewing, consider these tips:
- Seek out locations with clear skies and minimal light pollution.
- Many regions across the USA are expected to have excellent viewing conditions, particularly the Central, Southern, and Midwestern areas.
- Keep an eye on local forecasts, as cloud cover might limit visibility in parts of the Northeast and Pacific Northwest, including Washington state.
- If direct viewing on December 4th isn’t feasible due to weather, don’t despair—the Moon will still be around 99 percent full on Friday, December 5th, offering another fantastic chance to catch its brilliance.
Don’t Miss the Last Supermoon of 2025!
As December 2025 draws to a close, don’t miss your chance to witness the spectacular supermoon, also known as the Cold Moon. This astronomical event, visible throughout the USA, offers a stunning display of our celestial neighbor appearing larger and brighter than usual. Mark your calendars for Thursday, December 4, 2025, especially around 6:14 p.m. Eastern Time (ET) for peak illumination, and plan to find a spot with clear skies to enjoy the view. Whether you’re in the Central, Southern, or Midwestern areas, or even if you need to catch it being 99 percent full on Friday, this supermoon in December 2025 promises to be a memorable celestial highlight. Grab your binoculars, gather your loved ones, and look up to marvel at the final supermoon of the year!
About the Author
