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Today we are going to take a look at the night sky for later December, particularly the Ursid meteor shower coming up on the 21st/22nd of December. I will also go over the major constellations that are visible.

We will start with sunset on the 16th. The sky hasn’t changed too drastically since early December, but we are going to push through the month a little and take a look at some of the things that we haven’t covered in previous pieces. Just as the Sun sets, we have the square of Pegasus up nice and high just above the planet Saturn. Even very early in the evening we’ve got plenty of interesting things to see ranging across the sky to the south. From the Square of Pegasus, heading east we’ve got the constellation of Andromeda, then Perseus and then Auriga, all spread out from the northeast stretching up to the south. These are among the first things to become visible. Pushing later, the sky will continue to darken. Jupiter will rise into the sky nice and early in the east, quickly followed by Orion. All of Orion is up by just 8:15, still nice and early in the evening. This brings us into true darkness with even more constellations visible. Continuing that chain from Pegasus, Andromeda, Perseus and Auriga, we’ve now got Gemini with Jupiter over in the east. Underneath Auriga and Perseus we have the bright star Aldebaran for Taurus and lower again is Orion. The due south region of the sky is going to look pretty empty, but there are other constellations in here like Cetus. From below Aries and next to Taurus, over to Pisces and Aquarius, Cetus pretty much covers the whole space. There are two stars that should be visible, one at each end. Cetus takes up a huge chunk of the sky under the arguably more famous Aries and Pisces. those constellations are pretty tough to see themselves and Aries in particular isn’t very big.

Just before we push all the way on to morning time, I hope that some of you caught the Geminid meteor shower that peaked on the 13th and 14th, the weekend just passed. There’s still a couple of meteors coming from that shower as we push into December, but they will pretty much be exhausted by the time we come through to the 16th and 17th. Luckily there is another meteor shower coming up later in the month, but before we push later in the month we’ll get ahead towards morning time. Now that we’re through to the middle of the month Mercury isn’t going to be as prominent in the morning. It’s still there on the 17th, but certainly not as easy to see or as bright as it would have appeared during its greatest elongation back on the 7th. Looking at the sunrise sky at 7:00 and the sky is reasonably dark. Up at the zenith now is the Plough or the Big Dipper, with its handle arcing down to Arcturus in Boötes and then spiking on to Spica in Virgo. Corvus is the nice diamond shape just under Spica.We have Leo up nice and high towards the southwest, so of course Cancer the Crab must be in between Leo and Gemini. Pushing all the way through to sunrise, there is that little glimpse of Mercury, but we’re not seeing any Venus anymore, it is out of the morning sky, at least to us.

Coming all the way back to sunset, we’re going to go through to the solstice on the 21st. It’s the shortest day of the year and the longest night of the year, so we’ve got our sunset nice and early, just a little bit after 4:00. There are bright things emerging in the sky, even in the city, by just 5:30. We have those same constellations visible that we were looking at previously in the south, but we’re going to turn around to the north and take a look for the radiant of the Ursid meteor shower. It is up in Ursa Minor, though they aren’t called Ursa Minorids. They’re peaking there on the 22nd of December, just after the solstice. We’re going to move from sunset on the 21st through to just after midnight, the beginning of the 22nd. Out of a zenith hourly max of 10 to 50, we’re starting with a rate of 3 to 13, with us maybe seeing 1 to 3 in the city. The Ursids radiant isn’t too low in the sky, just a little bit lower than the North Star at sunset. By morning time, they’ll be higher, closer to the zenith, so that’s going to give us a better view. As we push through the night the zenith hourly rate rises and the amount that we’re potentially seeing in the city rises as well. Coming up to sunrise it keeps going up and the radiant comes up above the North Star. Just before sunrise we’re seeing 6 to 29 and 2 to 10 in the city. We will push out to the countryside because that should give us a better view of this meteor shower. The amount we should see jumps to 5 to 26, which really isn’t too bad. The Ursids are definitely more of a medium meteor shower, compared to the very impressive Geminid meteor shower and other big meteor showers during the year.

The current rate of meteors continues rising as we come through the day on the 22nd, so it’s very likely that that meteor shower will reach its peak while the Sun is up for us here in Ireland. It peaks just a little bit before sunset, with the the current zenith hourly rate reaching 10 to 50. Locally, that would be giving us 7 to 36, because this radiant is so much lower in the sky than the actual zenith. This is during the day for Ireland, but it means that once it actually gets dark again on the 22nd, we’re still seeing more than we did just after sunset on the 21st. The rate drops to 9 to 45, with us really seeing about 6 to 30. This means we would be seeing 9 to 45 if the radiant was at the zenith, but given how low it actually is in the sky we see a little less. It looks like we are catching the beginning of that shower on the 21st and then the end of that shower on the 22nd. As we move through the 22nd the rate is going to continue disimproving, but it remains higher for most of the night of the 22nd and into the 23rd than we would see the night of the 21st into the 22nd. That’s the Ursid meteor shower coming up really the night after the solstice, but you can begin seeing them the night of the solstice. In particular, if you didn’t manage to catch the Geminid meteor shower, which is just passed and is the best one according to many metrics, you can at least head back and check out one of the recent pieces on this website where I go through the Geminids and their parent body.

Now that we’re out in the countryside on the shortest day and the longest night of the year, at just 5:30 there’s still some sunset glow in the sky, but we’ll have the summer triangle still up, nice and visible and we’re going to have parts of the outer limb of the Milky Way. Pegasus and Saturn will be very much above the south, really in the middle of the sky. The same pattern of stars, continuing down towards Auriga and just the beginning of Gemini, is visible as well. In a dark sky we’re getting a much better view of the Hyades in Taurus and the Pleiades, both very clear as soon as the Sun goes down. We’ll keep pushing through to actual darkness, coming up to just 7:30. There is a glow from the Milky Way coming up through the summer triangle, but it is low in the west very early. Even though we’re looking at this pitch black sky, it’s still only 7:30, it wouldn’t even be fully at this time during the summer. We’ve got a fantastic view of Orion, even the lion skin portion of Orion here at the front, what many people would consider the bow of the hunter, even though it’s usually depicted as a lion skin. We’ve got Gemini very clearly in the east and if we continue tilting around, a really nice view of Ursa Major in its totality low in the north. To get a better view, we will have to wait again until morning time.

Coming up to morning time, we’ll go through to Orion setting, just about just six o’clock so that Orion is still on the horizon, partly set instead of fully set. At this time we’ve got Leo nice and clear, but not as distinct as some of the constellations we’d see in the evening, we’re going to have to wait for the Sun to come up and block out some of the fainter stars. We’ve got part of the Summer Triangle already back up in the morning to the east, because it’s been down for most of the night. We are now in mid winter, or close enough to midwinter to have a similar effect. Taking a look at the region of the sky due south, just under Leo, the constellations aren’t quite as famous. In a dark sky you should see a wiggly line of stars, one of the snakes in the sky. There are multiple snakes in the sky, this one is the water snake, Hydra the Water Snake as distinct from Serpens the Serpent which is just above the sunrise, , Serpens being carried by Ophiuchus. For Hydra, you might see that snake like shape, but it’s not one of the more famous or easy to notice constellations. Through to the sunrise we still just barely have Mercury, it’s still just about clinging on in the morning though, of course much lower. With the Sun coming up and blocking out some of the fainter stars, we can see those shapes of the more famous constellations like Leo even more easily, and our shape of Ursa Major nice and high in the sky.

That’s some stuff that’s coming up for the end of December. I will take a closer look at the very end of December, the 25th to the 31st, in a future piece when we’re a little bit closer to the end, just to keep you up to date on what you’re going to be able to see for the longer, darker nights of the year. I hope you do get to see as many of these objects as possible, I hope you see the Ursid meteor shower and I hope that you enjoyed this piece, if you did, please do like it and if you like this kind of content, please subscribe to this website and my YouTube channel. Thank you very much for reading and hopefully I’ll see you back here next time.