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What's Up for October 2017

It's actually clear outside for once, and those twinkling stars are beckoning you out into the autumn night. But which is which?

When you are a beginner, there's a lot to learn in a short time. But you don't have to go it alone – we're here to help. This page will get you started. Even so, the only way you can really do it is to go out and see for yourself.

Oh, the usual Health and Safety warning. It can get pretty cold out there at this time of year, so put your coat on. This is not your mother talking, it just makes sense. The more comfortable you are, the better you will enjoy stargazing. Who cares if it's an anorak – no one can see you. And a bobble hat helps, too. A hoodie? That's up to you, as long as the hood doesn't actually cover your eyes when you look up....

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 October 2017

Wrong way round?

Now don't be a clever dick 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! Best to use a tablet or phone!

It 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 10 pm, at the start of the month at 11 pm, or by the end of the month at 9 pm. All times are BST, but we go back to GMT on Sunday 30 October so at the end of the month everything will be an hour earlier.

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

Where are the planets?

What, no planets on the map? That's because there aren't any bright planets in the evening sky right now. Actually, Saturn is around but it is low in the west just after sunset and is quite tricky to spot. Mars and Venus are in the early morning sky, and in fact are very close together on the 5th and 6th.

Venus is much brighter – you can't miss it, over in the east, shining brilliantly quite low down about 6 am. Poor old Mars looks quite miserable alongside it. If you can view the pair through a telescope you'll also notice that Mars is only about a third the size of Venus. This is partly because it's a smaller planet anyway, but mostly because it is much farther away at the moment. But give it a chance – by next July it will have made its way into the late evening sky and will be at its closest to us since 2003.

Jupiter and Mercury are too close to the Sun to be seen.

For a detailed list of things happening in the sky, click here.

Making sense of the stars

One constellation or star group that many people recognise straight away is the Plough. This is low down in the north at the moment, so turn the map upside down and you will  see the seven-star pattern in the north-west. OK, it might not look much like one of those spiky things you see in fields being towed around by a Massey Ferguson, but these names were given a long time ago, long before Massey met Ferguson. So think of it as a saucepan instead. Once you have found this, you will get an idea of the scale of the map compared with the sky.

Next turn round so you're facing south and look over your head for the three stars marked Deneb, Vega and Altair. Vega is also one of the brightest stars in the sky. Altair has two fainter stars on either side of it, though in a poor sky you may only see the upper one. These three stars, Deneb, Vega and Altair are called the Summer Triangle, even though they are still visible well into autumn.

Once you have found the Summer Triangle, you can now start to look for some constellations. There's Cygnus, the Swan, also known as the Northern Cross. It is a large cross-shape with Deneb at the top, marking the tail of the swan which flies down the Milky Way with outstretched wings. Fair point. You live in Neasden or Newcastle and can't see this Milky Way which is shown on the map. You'll just have to take our word for it that it's there. To find out more about Cygnus, including why it is unsuitable for children, click here. One of the best-known stars in Cygnus is Albireo, a fairly faint star marking the head of the Swan, or the foot of the Cross. Midway between Altair and Albireo is a rather cute constellation called Sagitta, which means Arrow, along with two neighbours, Vulpecula and Delphinus.  They may be small, but they have a lot going for them, so take a look.

Map for October 17 with constellation names
All maps produced using Stellarium software.

Other constellations to look for

Going back to the Summer Triangle, find Altair and follow the line of the three stars down towards the south until you came to a brightish star as shown on the map, Alpha Capricorni. You should be able to pick out that this consists of two stars – a double star.  Actually, the fainter star is about six times the distance of the brighter one.

Look about half-way up the sky for a large square of stars. To tell the truth it isn't a perfect square, but give us a break, we have to make the most of the shapes the stars make.  It's known as the Square of Pegasus, and represents a flying horse. Fortunately for those of us down on Earth, this horse has no rear end. 

You can use the Square of Pegasus as a signpost to find other constellations. Follow the diagonal down to the lower right an equal distance and you come to a faint group of stars known as the Water Jar of Aquarius.  You'll probably need binoculars to find this in a town sky. It's easily recognised by its arrow shape, which looks a bit like a fighter plane with swept wings.  Though it's not the brightest part of Aquarius, it's a good pattern that helps you to find the other stars.

Follow the right-hand edge of the Square right down to the horizon and you'll see the bright star Fomalhaut, in the constellation of the Southern Fish.

If you want a map with all the constellation names on it, click here

Shooting stars...

For a few nights around the 22nd you might see some Orionid meteors, which occur each year at this time. They won't start to appear until after 10 pm BST, because that's when their radiant (to the top left of Orion) rises in the east. The radiant is the direction from which they appear to stream, so they will appear to come from a point below Capella at the top of the map. Don't expect hundreds – one every ten minutes or so is usually a reasonable number, but you might just be lucky and see more.

This year, their activity peaks with the Moon nearly new – that is, virtually in line with the Sun – so moonlight will not be a problem. The darker your skies the better, but don't give up on them even if you live in a town. You just need an awful lot of patience. You can read more about the Orionids in this guide

What about the Moon, then?

It begins the month at gibbous phase just after first quarter – that’s a half Moon – which was on 28 September, and then full Moon this month is on the 5th. Last quarter is on the 12th, then comes New Moon on the 19th. You might just see the crescent Moon in the western twilight on the 20th about half an hour after sunset, but it will be very low down and thin, and you will stand a better chance on the 21st or 22nd. Finally there's first quarter on the 27th. Sorry, no eclipses this month. 

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