Have you ever seen a Supermoon rise above the eastern horizon at dusk? It's one of the most spectacular natural wonders of all, and it will happen for the only time in 2017 at dusk on Sunday, December 3.
When our natural satellite rises fully illuminated in December it's usually referred to as the Cold Moon. The falling temperatures in the northern hemisphere can make this full moon a challenge to observe, but this year it will be worth the effort.
A full moon occurs every month (once every 27.3 days, to be exact) when it's on the opposite side of Earth as the sun, but some are more special than others. The moon orbits Earth in an elliptical path, so it has a furthest point (called lunar apogee, which occurred in June) and a closest point (perigee). It's the latter that happens close to December 3, resulting in a disc that will look slightly larger than usual as it rises: also known as a Supermoon.
When is the Cold Moon in December?
The last full moon of 2017 will occur at precisely 15:47 Universal Time (UTC). At that exact time Earth will be directly between the sun and moon. That's 10:47 Eastern Standard Time (EST) in the United States, and even earlier in the day heading west. However, to catch a glimpse of the beautifully pale orange Cold Moon rising, all you need to do — wherever you are — is to look east at dusk as the sun sets in the west.
Why is it called the Cold Moon?
December's Full Moon has in the past been called the Cold Moon, and sometimes the Frost Moon, by Native American tribes for rather obvious reasons: It's the onset of winter in the Northern Hemisphere. The lengthening nights and its timing just before the winter solstice have also led it to be called the Full Long Nights Moon.
When is the next Full Moon?
The next New Moon is on Monday, December 18, so look out for a beautiful Crescent Moon for a few days afterwards. However, precisely 27.3 days after the Cold Moon comes the next Full Moon on Tuesday, January 2, 2018. Known as the Full Wolf Moon by some Native American tribes, it's also a Supermoon. In fact, the Full Wolf Moon is actually even closer to Earth than the Cold Moon, so it should appear even larger. It should be a fine sight to ring in the new year.