The Moon before Yule

December's full moon; an occultation of Mars; the Geminids meteor shower

There is a full moon coming up. I did last month’s full moon as a little video, and fully intended on doing the same this month, but I have come down with covid, gah! I’m fine, it’s mild, but I’m a bit of a grotty mess and no-one needs to see that… Instead, please enjoy this much-more-lovely painting: Night, by Evan Marchuk.

First things first, some old names for December’s full moon: Moon before Yule, Oak Moon and Full Cold Moon. Really very wintry and atmospheric. Brrr…

This full moon will fall on the morning of the 8th at 4.08am. This being so early in the morning it will look just as full in the evening hours of the 7th as it will in those of the 8th, so either will be excellent for viewing.

But there is something else special coming up in the early hours of the 8th. You may have noticed Mars in the sky, looking particularly shiny and bright. That is because it is going to be at opposition on the 8th. When a planet is at opposition it is essentially acting like a full moon, that is: it is in the opposite part of our sky from the sun, and so from our view the sun is fully lighting it up. But opposition is also the moment that the planet is at its closest to us, so it really is the best time to have a look at it through binoculars or a telescope.

In addition to all this Mars is going to be in conjunction with the moon on the night of the 7th and early hours of the 8th, which means that they will be travelling together through the sky. And in fact at one point they will get so close that Mars will be occulted by the moon, which means that it will slip behind it. This will happen at around 5am on the 8th, and it will reappear about an hour later.

Rare and exciting. Do try to spot it if you are awake.

Some other things to look out for this month:

The Geminids meteor shower will fall over the night of the 13th-14th. This is one of the most dependable meteor showers of the year so really worth looking out for, however the moon will still be pretty bright, which can reduce visibility.

And there is a conjunction of Jupiter and the moon on the 29th. They will rise together at about 4.30pm.

This information comes from my book, The Almanac, and The Almanac 2023 is out now. All of this at your fingertips whenever you want to pick it up.

Wishing you clear skies!