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What's Up for January 2018

The stars are out. It can't be all that hard to learn the sky, can it? But then you get out there and the stars all look, well, all more or less the same. So what's the secret? Read on and find out.

But before you do anything these days you have to carry out a Risk Assessment. Being hit on the head by a shooting star? No chance. Being scared out of your wits by next door's cat suddenly jumping on you? That's more likely, assuming next door have a cat. Being frozen to the guts? Even more likely this weather, but at least you can do something about that one by putting on two of everything (within reason, of course). It is January, after all, and global warming doesn't seem to apply at night.

You will need a star map, and you will need to know how it works. This may seem obvious, but there is a knack to understanding these things. Here is our map for this month:

Sky for January 2018

Wrong way round?

Now don't write in and tell us that we have the points of the compass all wrong. This is a map of the sky, so you have to hold it over your head. When you do this, east and west will be the right way round. How you hold your computer above your head is up to you! Maybe you have one of those app thingies that tells you where the stars are, but read on to find out the important things to look for.

The map shows the whole sky, so the scale is quite small. Normally you turn to see different parts of it, so to see the view looking north, for example, hold the map upside down with north at the bottom.

The map shows the sky in the middle of the month at about 8 pm, at the start of the month at 9 pm, or by the end of the month at 7 pm.

TIP If you aren't sure of the direction of north from your location, click here for a page on Getting Your Bearings.

Find Orion

At this time of year one of the best constellations (star patterns) of all is in the sky – Orion. Look just to the left of your south point and you should spot three stars in a line, with four other stars forming a sort of box around them, as shown on the map below.

January 2018 sky looking south

Orion has more bright stars than any other constellation, so it shows up no matter how bad your light pollution is. You can't mistake it for anything else in the sky. As well as the three stars in a line there are two brighter stars, called Betelgeuse and Rigel, at top left and bottom right.

The three stars in a line are known as Orion's Belt. Orion is meant to represent a hunter, usually facing westwards towards Taurus, the Bull. Dangling from his belt is a sword, which is the line of fainter stars just below the belt where the map is marked M42. Check out our constellation guide to Orion to find out more about spotting the Orion Nebula.

You can follow the Belt stars up and to the right (the west) to the bright star Aldebaran, in Taurus, and beyond that to the best star cluster in the sky, the Pleiades (pronounced Ply-a-deez). Then following the Belt stars down and to the left you get to Sirius, in the constellation of Canis Major, the Greater Dog.  Sirius is the brightest star in the night sky (note: smart-alecs love to point out that the brightest star in the sky is the Sun so you always have to be very careful to say the night sky to avoid giving them the satisfaction of doing so).

Other constellations to look for

Also look out for Auriga, some distance directly above Orion. Its brightest star, Capella, is almost overhead from the UK at this time of year. There is a little group of three fainter stars just to one side of it, and four other stars in a big pentagon making up the rest of the constellation.

Farther west from Taurus is Aries, whose brightest stars are a little group of three. The faintest of these, Gamma Arietis, is a rather pretty double star which you can see using a fairly small telescope. Worth a look, as the two stars are of different colours.

On the circular map at the top of the page you can pick out some other patterns. Look for the Winter Triangle of three bright stars, starting with Betelgeuse in Orion. The other two are Sirius and Procyon. This will be around well into the spring, so you can look for it later in the year as well.

Then look over to the west and see if you can spot the Square of Pegasus. It isn't as bright as the stars of Orion, but it's a good signpost to the other constellations in the area once you've found it, particularly Andromeda and the Andromeda GalaxyPerseus and Cassiopeia.

Where are the planets?

Now for the bad news. There are no bright planets at all in the evening sky at the moment, and you'll have to wait until April to see anything really good, when Jupiter comes into the evening sky. Right now, even Jupiter doesn't rise until about four in the morning. 

If you are up before sunrise,  you'll see Jupiter and Mars quite close together in the south-east at about 6 pm. In fact, at the start of the month they'll be really close, and worth a look if you can manage to peer out of the window that early. It's quite unusual to see two bright planets so close together. Between the 5th and the 8th you'll see them change positions, if you get clear skies, with Mars being the fainter of the two, moving from right to left past Jupiter. 

Shooting stars

A Quadrantid meteor photographed in January 2012

The annual Quadrantid meteors are usually one of the best displays of shooting stars of the year – and wouldn't you know it, they take place on 3–4 January so you will need a cast-iron will (and probably get cast-iron other parts of your anatomy as well) to observe them. But there's a big snag this year – our old friend the Moon. This will be just after full phase, so it will light up the sky and make it quite tricky to see many meteors.

If you do decide to take a look, during the night of January 3 to 4 you may see quite a few of these fairly slow and bright meteors coming from the northern part of the sky, though you can look anywhere in the sky to see them. The later in the night you observe, the better the numbers are likely to be. 

You may hear that numbers will be over 80 an hour. While that's an official figure, it covers all meteors, bright or faint, under ideal conditions. Under the circumstances, you might be lucky to see one every few minutes. 

For more details of the Quadrantids, check out this page. And to find out how to make really useful observations of meteors, look at our online guide, Observing Meteors.

What about the Moon, then?

It begins the month just coming up to full Moon, which is on the 2nd. Last quarter is on the 8th, then comes New Moon on the 17th. You might just see the crescent Moon in the western twilight on the 18th about half an hour after sunset, but it will be very low down and thin.  There's first quarter on the 24th, then finally there's another full Moon on the 31st.

Some people call the second full Moon in a month a blue Moon, and the media will probably be full of it. But this is a bit of an error, and there's no astronomical reason for it. 

Sorry, no eclipses this month. But we have a whole section of the website devoted to the Moon and its features.

The full Moon in January is very high up and bright, so here are some full Moon facts (and one that isn't).

The village of Turville, Bucks, photographed by the light of the full Moon in January 2015. The village is famous as a location for The Vicar of Dibley and Chitty Chitty Bang Bang, among others. Picture copyright Robin Scagell
  • When the Moon is really high up, like in that nursery rhyme that claims it is as bright as day, you can't see any colour in anything that's illuminated by the Moon only (that is, out in the country where there is no light pollution). This is because your eyes are not sensitive to colour in dim light.
  • The sky close to the Moon appears bluish, just as it does by day. This is what makes you think that moonlight is blue, and is why they use a blue filter in the movies when they want to pretend that the scene is lit by moonlight.
  • Actually, moonlight is slightly redder then sunlight.
  • If you take a time-exposure photo by moonlight, without any light pollution around, the colours appear just as they do by day. The camera can go on building up light and show the true colours, unlike your eye.
  • Those stories that there are more hospital emergencies and murders when the Moon is full are nonsense. The only reason people think this is that the Moon is more noticeable when it is full than at most other phases. And most people think it is full for two or three days on either side of the actual date, so there are several days in the month when it appears to be full. So that increases the chances of people linking anything with the full Moon.

Get more helpful info

OK, you've read all this for nothing, now comes the plug. This page is brought to you by the Society for Popular Astronomy, which is a really great society to join. It's based in the UK but there are members in other countries as well. It doesn't cost much to join, and there is a special rate for Young Stargazers. At least take a look at what we have to offer.
Text by Robin Scagell