The Moon
The Moon In December
It’s the last month of 2024 and it begins with a new moon and very dark evenings. First quarter arrives on cue a week later and brings with in a brightening night sky. Although, at this time of year, we get many more hours of darkness in the evening running up to moon rise than at other times.
Full moon occurs in the middle of the month and the fainter night sky objects are drowned out by its light but we steadily regain the evening darkness as we trundle towards last quarter on the 22nd. We’ll enjoy very dark evening skies for the last few days of 2024 as we close out the year with a return to the new moon.
We’ve got some good librations to challenge us this month, with the best of them on the 16th when our neighbor reveals more of its northwestern quadrant than we’d normally see.
Moon Name
December’s full moon is known as appropriately enough the Cold Moon, which I don’t suppose needs much explanation. Other names for this month’s full moon are the Oak Moon and the Long Night Moon, the latter very well describing the darkness at this time of year.
Viewing Summary
| Dark Evenings | Dark Mornings | Dark Night | Evening Moon | Morning Moon | Librations |
| 1-4, 21-31 | 2-9, 27-31 | 1-5, 25-31 | 7-18 | 12-23 | 14, 16, 27, 28 |
Moon Phases, Rise & Set Times
Whether you are planning to observe the moon, or you want to make sure to avoid it, use the table below to discover when the moon will be above the horizon this month. The ‘Illumination’ column shows how bright it is going to be – the higher the %, the brighter the moon.
Moon Table Notes
- A=Apogee (furthest approach), P=Perigee (closest approach), FQ=First Quarter, LQ=Last Quarter
- All times are for Kansas City (DST). However, these times will be approximately accurate for your local time zone wherever you are in the northern hemisphere. For example, if you live in London, UK, the moonrise and set times will be no more than an hour different from those shown in the table above.
- There are two moonrise columns in the table, this is because each day is timed from midnight to midnight. On some days in the month the moon is already in the sky at midnight, therefore it sets first before rising again later in the day. On other days, the moon is below the horizon at midnight. On those days it rises first before setting later in the day.
- The data in the table comes from timeanddate.com
Visualization Of The Moon’s Impact
The following chart shows a visualisation of when the moon is above the horizon and below. This should make it easier for you to plan which nights offer the darkest skies and which provide the best opportunity for observing the moon itself.
First & Last Quarter Moon Locations
The two pictures below, from SkySafari 6, show the last and first quarter moons available to us in December.
We’ll see it reach first quarter on 8 December, when the moon will be passing through Auriga. First quarter is always best viewed in the evening, when the moon is higher in the sky. The image below shows the moon’s location at 8:30 pm when it will be 51° over the southern horizon.
Last quarter, which is better for lunar gazers outside in the morning, happens on the 22nd of December. The second star chart below reveals that the moon is in Virgo that night and 66° above the southeastern horizon at 6:00 am.
Click on the pictures for full screen versions.
Librations
The moon wobbles as it orbits Earth. These wobbles are known as librations and they show us parts of the Moon’s surface which are usually on the ‘dark side’. This means that we can actually see around 59% of the lunar surface over the course of a month. Keen moon watchers look for these librations so they can spy craters not normally visible to us.
More information on how to read the images is provided at the bottom of this page.
Guide to libration images
Where the two blue lines cross shows the center of the lunar surface when there is no libration. The blue dot shows the center of the Moon’s surface, i.e. where the Earth would appear overhead if you were standing on the lunar surface. The yellow dot (cone) shows where the Sun is overhead.
Use the images above to see where each libration occurs this month and how large it is. Firstly, imagine a line running from the crossed blue lines and through the center of the blue dot. Extend this line on to the edge of the Moon’s surface. Where the line meets the edge is where the libration is most noticeable, this is shown as a red arrowhead in the diagram on the right.
Secondly, to see how large the libration is, note the distance between the crossed blue lines and and the blue dot. This is shown as the double-headed green arrow in the diagram. The larger this distance, the more of the ‘dark side’ of the Moon we can see.
The images above are generated on this NASA website.
