December 2023 Night Sky AstronomyNight Sky viewing guide for December 2023 including Moon phases, occultation of Mars, conjunctions, Geminid meteor shower and Deep Space Objects to see.
Decembers Moon Phases
In December, winter sets in and the Full Moon is called the Cold Moon. It is also called Long Nights Moon, and the Moon before Yule.
Full Moon and New Moon for December 2023
December 2023 Last QuarterTue 5th Dec
December 2023 New MoonWed 13th Dec
December 2023 First QuarterWed 20th Dec
December 2023 Full MoonWed 27th Dec
December is the winter solstice which occurs at 03:21 UTC. The South Pole of the earth will be tilted toward the Sun, which will have reached its southernmost position in the sky. The solstice marks first day of winter (winter solstice) in the Northern Hemisphere and the first day of summer (summer solstice) in the Southern Hemisphere.
December Planets
Mercury will be at its greatest eastern elongation on December 4th, however there is no moon, stars or planets nearby to aid in its locating.
Venus is a bright morning planet, and Venus and the Moon are close together on December 9th when you can see Venus hanging just to the left of the Moon along with Spica on the right.
Mars is too close to the sun to be visible.
Jupiter is a splendid object visible in the southern sky as soon as darkness falls. Using higher magnifications you will see the yellowish flattened disc and as the four Galilean satellites. You should be able to follow the movement of these moons from night-to-night. It will be visible in the mornings from January to May, evenings from May to November, and mornings again from mid-December to the end of December.
Saturn is visible in the mornings from late January to early July, then in the evenings from July to December.
December Meteor Showers
The annual Geminid Meteor Shower takes place in December, with the peak on the 13th. It's one of the favourite observing events of the year with many bright meteors expected to be visible.
The Geminid meteor shower reaches peak activity around 14th December, making 13th and 14th December ideal times to look for meteors. The Geminids provide good activity prior to midnight as the constellation of Gemini is well placed from 10pm onward. Around the peak of the 2021 Geminid meteor shower, the Moon is just a few days old and won't brighten the sky sufficiently to block meteors.
The Ursids is a minor meteor shower producing about 5-10 meteors per hour. It is produced by dust grains left behind by comet Tuttle, which was first discovered in 1790. The shower runs annually from December 17-25. It peaks this year on the the night of the 21st and morning of the 22nd. This year the moon spoils the show as it will be very bright in the sky. Best viewing will be just after midnight from a dark location far away from city lights. Meteors will radiate from the constellation Ursa Minor, but can appear anywhere in the sky.
December Deep Space Objects
The Orion Nebula (M42 and M43) are prime targets in the winter months hanging in the South Eastern sky. They are easy to locate as they form the sword hanging from Orion's Belt.
Taurus contains two glorious winter deep sky objects - the Hyades and Pleiades star clusters. Both can bee seen with the naked eye and are wonderful sights in binoculars, and small telescopes will further reveal the glittering array of bright, blue stars that make up the Pleiades. The Crab Nebula (M1) is almost directly overhead during the early evening hours. You do need a dark, clear sky, for to see the Crab nebula as it has a tendency to get lost in light pollution. It may be just barely visible as a dim patch of light in good binoculars, whilst telescopes greater than 3" should be able resolve more detail.
A short hop into neighbouring Auriga will bring you to the three exquisite open clusters - M36, M37 and M38 all of which can be spotted with binoculars and lie in the region between Beta Tauri and Delta Aurigae.
With dark skies, you should be able to spot the double cluster Perseus with the naked eye. It's another great target for small telescopes and consists of the clusters NGC 869 and NGC 884.
The Andromeda galaxy is a favourite of mine, directly overhead in December and slowly setting towards the west during January and into February. This large galaxy can be seen as a faint fuzzy blob with the naked eye under dark skies, but its really best to see through binoculars. Through a telescope the Andromeda Galaxy looks quite diffuse. Use your lowest power; the full extent of the galaxy is huge - five times as large as the full moon. It is the most distant object you can see with your naked eyes being two million light years away.
