December full moon mimics the June sun
The last full moon of 2022 will come on the night of December 7-8. For us in the Northern Hemisphere, it’ll cross high overhead. Meanwhile, from the Southern Hemisphere, it’ll ride low in the sky. Why? Because a full moon is always opposite the sun. And – for us in the north now – the sun rides low (so the moon rides high). For the Southern Hemisphere, the sun rides high (so the moon rides low).
The December full moon will fall at 04:08 UTC on December 8, 2022 (10:08 p.m. CST on December 7). That’s the moment when this month’s moon is most directly opposite the sun as seen from Earth. It’ll be an eventful night for this full moon. Mars will reach opposition on this night. In other words, Mars is also opposite the sun on the night of December 7-8. Since both the moon and Mars are opposite the sun, it’s no surprise that these two worlds appear near each other. From some parts of Earth, the moon will occult Mars – pass in front of it – on the night of December 7-8.
December full moon mimics the June sun
Every full moon is more or less opposite the sun. And a full moon’s path through the night is opposite the sun’s path. So this December full moon’s path roughly follows the sun’s daytime path from six months ago, or six months from now. No matter where you are on Earth, notice the moon’s path on December 7-8. The Northern Hemisphere will see the December full moon rise to nearly the top of the sky, just as the sun does near the June solstice. The Southern Hemisphere will see a low moon, mimicking a low winter sun.
Here’s another way to look at it. In the Northern Hemisphere, the December solstice has the least amount of daylight of the year. Since there’s still about 24 hours in a day no matter how much daylight there is, the shortest day means it must also be the longest night. In order for the moon to stay up all night and remain roughly opposite the sun, it needs to take a longer path across the sky. The higher an object crosses the sky, the longer its path and the longer it stays above the horizon.
Names for the December full moon
Do you see why tonight’s moon is sometimes called the Long Night Moon?
But – like all full moons – the full moon of December has many nicknames: Long Night Moon, Full Cold Moon, Moon Before Yule. But no matter which name appeals to you, be sure to notice the moon’s high (or low) path!
Tracing the high path of the December full moon
Try this. Trace a line with your finger from east to west to emulate the sun’s path in December. If you’re in the Northern Hemisphere, you’ll be tracing a low arc above the southern horizon. Then, with your finger, trace another path high overhead. Now you’re emulating the moon’s December path, and you’ll see it’s a longer path than the lower one.
Little by little, we can watch the two paths come back into balance. Each month, the full moon will cross the sky at a slightly lower arc than the previous month. Each successive full moon will take less time than the previous one to cross the sky.
What about an equinox moon?
At March’s full moon, which is near the Northern Hemisphere’s spring equinox, the two paths – of the moon and of the sun – will be nearly the same. Then, near the June solstice, those of us in the Northern Hemisphere will see the sun cross high overhead during the year’s longest days. And, during the short northern summer nights, we’ll see the moon cross lower and spend less time in the sky.
And on the cycle goes.
Last full moon of 2022
This full moon is the last full moon of the Northern Hemisphere’s autumn – and Southern Hemisphere’s springtime – and it’s also the last full moon of 2022.
Plus it is the closest full moon this year to the December solstice, occurring just 13 days before the solstice. This solstice marks the start of winter in the Northern Hemisphere (and summer in the Southern Hemisphere). It falls on December 21. The January 2023 full moon is 16 days after this December solstice.
You’ll find this December 2022 full moon in Taurus the Bull, as shown on the chart below.
Enjoy December’s full moon! And don’t forget … the red object near it is Mars!
Bottom line: The 2022 December full moon happens overnight on December 7-8, 2022. It closely follows the path of the June sun. It’ll be near bright red Mars. And from some places it’ll occult or pass in front of Mars.