Your Christmas sky for 2019

If you’ve just got your first telescope for Christmas, you’ll be wondering what to point it at. This is a guide to some of the sights of the sky for December 2019.

First thing is to get the telescope working. This wouold be a whole book in itself, and sadly many telescopes have really poor instruction manuals, but the best we can do here is to direct you to our help pages. Most important is this one:

Starting to use your telescope

Here you’ll learn how to choose the best magnification to start with, and how to align the finder – that’s the fiddly little thing mounted on the top of the telescope, which really is essential. Even experienced observers make sure that their finder is properly aligned, as they wouldn’t be able to find a thing without it. Oh, maybe the Moon, but that’s about the limit.

You might also need this one:

Aligning an equatorial mount

130 mm reflector on equatorial mount
A 130 mm reflector on a German-type equatorial mount 

This is useful if you have a German-type mounting, which a lot of telescopes do. So if you telescope mount looks like the one at right, read that article first.

With those two under your belt, you are no doubt eager to get ‘first light’, which means what it says – your first view through the scope. So what should you look at?

The best object to start with is definitely the Moon. You know you’ve got it when you see it, and it’s an amazing sight through any telescope, with masses of craters and mountains all in sharp relief. In 2019 it’s actually not visible at all for a few days after Christmas, because New Moon (when it’s in line with the Sun) is on 26 December, but you’ll start to see it over in the western twilight from about the 28th onwards. It’s very low down to start with, over in the south-west as a thin crescent that sets soon after sunset, but by New Year’s Eve it’s visible for quite a while in the evening sky.

From then on it gets to be a thicker crescent every evening until it’s at first quarter on 3 January, when it appears as a half Moon. Then it gets closer to full each night. Full Moon itself is on 10 January, but for a few days on either side of full, the Moon is actually rather boring with little detail to be seen, so get your lunar observing done before then.

The planets

It so happens that just at the moment the bright planets are not very easily visible. Venus is in the evening sky, but really low down in the south-western twilight just after sunset. It’s close to the thin crescent Moon on the 28th and 29th, but it sets quite early. Although very bright, it’s not very exciting right now, as it is quite distant and just appears as a small disc. Its closeness to the horizon means that we view it through a thick slice of our own unsteady atmosphere, so its image will be blurry and probably rather spuriously coloured, as the atmosphere acts just like a prism and splits its light into colours. 

Saturn and Jupiter are both almost in line with the Sun, so can’t be seen, and Mars is only visible in the early morning sky (and is also rather distant), so you’ll have to be patient and make do with Venus for the time being. So that just leaves us with the rest of the universe to look at!

Prime targets

Here’s our map of the sky as seen from the UK for the end of 2019, created using Stellarium which you can download for free. We have marked just a few bright stars and constellations so as to avoid confusion. Bear in mind, though, that the map shows the whole sky, so the patterns may look larger in the sky than they do on the map. And the compass directions are correct when the map is seen overhead! The map is for the sky at about 8 pm, but if you are looking a bit earlier or later, the same stars will be there, but shifted to the east or west.

The Christmas sky for 2019. The compass points apply when the map is held overhead

First get your bearings, then pick out the key stars and constellations. You can use one of those app thingies on your phone to help if you have one, but try and learn the sky as a whole, and the relationship between the constellations as you go along, rather than just locating one object in isolation.

Target 1 – the Pleiades

Your targets for tonight are the Pleiades star cluster, the Orion Nebula and the Andromeda Galaxy – three showpieces of the sky. Start with the Pleiades (pronounced Ply-adeez), as the cluster is visible with the naked eye and is easy to spot. Use the bright star Capella, which is quite high up, to work out where to look. In some years there might be bright planets in this part of the sky, but this year they aren’t around to confuse matters.

Pleiades as seen through binoculars
Pleiades in binoculars. Credit Robin Scagell

Actually, binoculars are the best way to view the Pleiades, as the cluster is quite large and usually more than fills the field of view. But whether you use binoculars or a telescope (at its lowest magnification) you’ll see many more stars than you can with the naked eye. The cluster is known as the Seven Sisters, maybe because seven was always regarded as something of a lucky number; but nine of the stars are named, and people with good eyes can distinguish all of these plus maybe others. 

In reality there are over 1000 stars in this cluster, although a small telescope will probably only show around one or two hundred. It’s a young cluster, around 100 million years old (compare the Sun’s age of 4.6 billion years). In time, the individual members will drift away from one another and the cluster will no longer be a coherent whole, but we are talking about hundreds of millions of years here. The cluster is about 440 light years away.

Target 2 – The Orion Nebula, M42

Along with the Plough or Big Dipper (over in the north), Orion is one of the best-known constellations. Even if you never had it pointed out to you as a kid, it’s easy to find, over in the south-east at this time of year. The distinctive three stars in a line and the quadrilateral that surrounds them are very distinctive, and there’s nothing else similar in the sky. It’s the constellation with the greatest number of bright stars, so even in the city centre with a full Moon you can still see it with no problem. 

Orion is the Hunter, and it’s a personal name rather than a Latin or Greek word for something, as with many of the other constellations. He is facing Taurus, the Bull (which is a Latin name), and the usual constellation drawing shows him raising a club to clout the raging bull, with the three stars marking the belt around his waist. So they are known as Orion’s Belt. 

To find the Orion Nebula, look just below the three Belt stars and you should spot a little line of fainter stars, In city skies they are invisible to the naked eye, but binoculars will show them. If your telescope has a red-dot pointer rather than an optical finder you’ll have to guess the spot to look at, but again use the lowest magnification to make things easier. We’ve labelled the nebula on the map with its catalogue number of M45 to save space.

A drawing of the Orion Nebula
A drawing of the Orion Nebula made using 15 x 70 binoculars from Burnley, Lancs, by Mike Hezzlewood.

The nebula is a hazy patch, inside which are several stars. Don’t expect to see the lovely colours which show up in photos – our eyes are just not sensitive to colour at low light levels, and not even giant telescopes will show much colour (if you could look through one, which you can’t because giant telescopes aren’t designed for looking through these days). You’ll see a pale hazy glow – maybe not too spectacular in itself, but this is our nearest and brightest birthplace of stars, at around 1340 light years distant.

The Orion Nebula as photographed through a 200 mm amateur telescope. Credit Robin Scagell

In fact, the whole of Orion is really a giant cluster of newly formed stars. But don’t expect to see one pop into existence as you watch – they take tens of thousands of years to appear.

Target 3 – the Andromeda Galaxy, M31

Andromeda Galaxy
Through a telescope, M31 appears as a misty oval blur. You might also be able to see its two companion galaxies, M32 and M110. Photo: Robin Scagell

Now look fairly high up in the south-west and find the Pegasus, whose main stars form a general square. They aren’t as bright as the stars of Orion, but this is a fairly empty part of the sky so they show up quite well. Using the map, count two stars to the left of the star at top left of the square, then two faint stars above that, and you will see another misty patch, marked M31 on the map. In reasonable country skies it’s just visible with the naked eye, but in towns you’ll need binoculars or a bit of clever star-hopping with your telescope. This is the Andromeda Galaxy.

It’s a lot fainter than the Orion Nebula, but then it is a lot more distant. This is another galaxy, like our own Milky Way galaxy, in its own right. It is our sister galaxy in a group of several dozen that we call the Local Group, and it’s roughly the same size as the Milky Way. Your other objects targets were just a few hundred light years away, but the Andromeda Galaxy is a whopping 2.5 million light years away. So when people ask how far you can see with your telescope, you can confidently say ‘At least 2½ million light years’, but in fact even binoculars will show galaxies about 20 times farther away than that, if you know where to look. 

Photographs show that it’s a spiral galaxy inclined at an angle, which is why it appears oval. It may not be spectacular and whizzy, but it’s pretty amazing that you can view it through your telescope in your garden or wherever you are, looking up at that ancient light that left its galaxy 2½ million years ago and has been travelling through empty space ever since until it registered on your retina.

Now for the ad

If you’ve enjoyed finding these objects and learning about them, do consider joining the Society for Popular Astronomy. We have been helping beginners for yonks (since 1953 actually) and we just love stargazing and helping people find their way among the stars. Find out more here – and have fun with the stars!