What’s Up in the Night Sky? – December 2020

Fred Barrett | Dec 02, 2020

One marvelous meteor shower and another OK shower grace our sky this December. The first is the Geminid shower and it’s one of the best of the best each year. It peaks on the evening of the 13th and it’s our luck that the waning Moon is the slimmest crescent just before being a new Moon on the 14th. The shower is active from the 4th to the 17th. The radiant is just above Castor at the top of the constellation Gemini, the twins. Bright stars Castor and Pollux represent the ‘heads’ of the twins. Gemini rises in the east about 8 pm but good viewing really begins around 10 pm when the radiant has risen higher in the sky. Remember though, that the meteor trails close to the radiant will be shorter since the meters are coming directly at you. It’s better to watch for meteors more than 30 degrees away from the radiant where the perspective will allow you to catch longer trails. The radiant will be overhead by 1 am. The maximum hourly rate could reach about 150 meteors per hour under ideal conditions and that includes dim meteors too. A more likely count is about 100 meteors per hour.

The second shower is the Ursids. The radiant is above the dipper in the asterism called the Big Dipper that is part of the Ursid Major or Big Bear constellation. The Ursids peak on the night of December 22/23. Unfortunately, a first quarter Moon will hinder decent observation of this shower. Although the Ursids are considered a smallish shower with a maximum rate of about 30 per hour, I always go out for several nights to see to see what might turn up. The Ursids sometimes have a surge in their numbers.

Our last views of Jupiter and Saturn for several months will be spectacular. They will be low in the southwest just after sunset and about 2 degrees apart. They will be near 20 degrees above the horizon around 6 pm. They set around 8:30 pm. But this show continues. On the 21st they will appear to almost touch. They are so close and as a perfect companion, a waxing crescent Moon sits just 5 degrees below them. Earthshine will light up the dark side of the Moon in such a way that you will be able to see the whole moon. You have to go to where you have a clear view to the southwest horizon and you have to be watching almost exactly 30 minutes after sunset to enjoy this stunning conjunction. A low power telescope will let you see both planets in your field of view; that’s how close they are. Of course, binoculars will provide you with a wonderful view too. Minutes after, the 2 planets and the Moon set. I always tell you to follow Jupiter’s dancing Moons and this month is no exception but don’t forget Saturn. Saturn has a whole set of viewable moons that are so often overshadowed by its rings.

Look to the southwest just before dawn on the 12th. A very thin crescent Moon seems to float just above an alarmingly bright Venus. Mars remains a beautiful sight during the month as it rises higher in the south.

Highlights for December:

December 7: Last Quarter Moon.

December 12: Moon at perigee – 359,672 Kms.

The Moon passes about 1 degree above Venus at dawn in the southeast.

December 13: Geminid meteor shower peaks.

December 14: New Moon. Total solar eclipse in Chile occurs – nothing for us to see, sadly

December 21: Winter Solstice occurs at 5:02 am EST. This is the longest night of the year.

December 24: The Moon is at apogee – 402,660 Kms. Oh yes, it’s also Christmas eve.

December 29: Full Moon. This Moon is known as the Full Cold Moon or the Full Long Nights Moon. I’m not looking forward to December’s long cold, dark nights – the start of many until spring. But my fireplace is friendly and warm on a blizzardy evening and hauling in wood is good exercise I think … My biceps look pretty big by April!! Well, sort of…

That’s a wrap. Merry Christmas and Happy Holidays!

Remember, it’s always a great month for looking up!

“The Beginner’s Observing Guide by Leo Enright is an invaluable companion for adventures in the sky. It also contains useful star charts. It can be ordered from the Royal Astronomical Society of Canada at www.rasc.ca/publications. A subscription to our very own excellent Canadian astronomy magazine “SkyNews” can be arranged at the RASC website as well.

Let me know how your observing has gone this month especially if you saw anything unusual. I got a few emails last month reporting meteor sightings and also strange satellites flying in formation across the sky. Check the SpaceX website for an answer about the satellites. I enjoy the feedback. If you have any questions or suggestions you can contact me through this paper or email me at This email address is being protected from spambots. You need JavaScript enabled to view it. .

Clear Skies! Fred.