It's August and holiday time. With luck you'll be able to get away to place with a darker sky than you're used to, or at least stay up a bit to make the most of whatever you've got. And at least you won't get frostbite. But how do you make sense of all those stars?
That's where we come in. Use our easy-to-follow sky guide and you'll be out there stargazing in no time. 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's our map for this month:
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.
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 mid August at about 10.30 pm, at the start of the month at 11.30 pm, or by the end of the month at 9.30 pm. All times are BST.
|TIP If you aren't sure of the direction of north from your location, click here for a page on Getting Your Bearings.|
This being summer, the best way to find your way around the sky is to use the Summer Triangle. Actually this is not as obvious as it seems, because this triangle still remains visible well into the autumn and even the winter, but the fact is that it's a key feature of the summer skies so we might as well stick with the name.
Find it by looking right overhead to find a really bright white star, Vega. It's the only bright star close to being overhead, so ignore all other stars and look really high up. The next star of the triangle, Altair, is halfway between Vega and the horizon. Altair has a fainter star on either side of it – look at the map to get the idea. The other star is Deneb, which is a bit lower down towards the eastern horizon than Vega. If you can't spot these three stars straight away, remember that the map above is on quite a small scale, so think big and you should spot it.
Many people recognise The Plough, which if you want to get your bearings is over in the northwest. We've picked it out on the map. If you think of the Plough as a saucepan, then follow its handle round towards the horizon, you come to a bright star called Arcturus, which is about the same brightness as Vega but low down in the western sky. It's also slightly yellowish, and if you thought all stars were white, compare it with Vega to see the difference.
Now use the map below to find more patterns nearby, but don't expect to see those convenient lines helping you to see the patterns. If you do see them, consult an optician or give back those glasses your friends gave you on 1 April.
All maps produced using Stellarium software.
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. Use this to find some other interesting objects, and the constellation of Vulpecula, by clicking here.
This is the time of year to look way down on the southern horizon for the constellation Sagittarius, which form a sort of teapot shape, But unless you have a good, clear night and are well away from city lights, you might not see the stars at all well.
There are plenty of nebulae and clusters visible with binoculars in this part of the sky, so check out our guide to them.
To the left of Vega is Hercules, whose most obvious feature is a parallelogram of stars called the Keystone, though it isn't particularly bright.
The map shows the Milky Way as a pale band crossing the sky. This is a good time of year to look for it, though you won't see it from light-polluted areas. The best chance of seeing it is high up in Cygnus, but if you go on holiday to a dark-sky area it can appear so bright you will wonder why you can't see it at home.
If you want a map with all the constellation names on it, click here.
Our map this month doesn't show any planets (all right, no planets apart from Earth). But don't give up. Saturn and Mars are also around, but if you have never seen them you'll have to be quick because they are setting in the southwest soon after the Sun. The time to look is from around 9.45 to maybe 10.15 pm, while the sky is still fairly light, and just before the time that our map shows. They are the brightest objects in the southwest, though the star Antares is only slightly fainter, farther east (to the left) than the two planets. On 3 August the Moon will be right between the two of them.
|The view looking southwest at 9.15 pm on 24 August|
Saturn is the higher and more easterly of the two, at least for most of the month. Mars is moving quite fast in an easterly direction. So if you start watching at the stars of the month the two planets are quite well separated. They get closer and closer together until by around 24 August they're quite close together, with Mars right below Saturn. After that date it starts to move farther east than Saturn, though it's close to the horizon and you need to look at just the right time to catch it.
If you have a telescope you can see the rings of Saturn but with it being so low in the sky they will probably not be very distinct. But you won't see much on Mars – it's really distant now and you'll be lucky to see anything more than a tiny disc, even if you have a good telescope.
Venus is in the morning sky, rising about 3.45 am BST over in the southeast. Jupiter and Mercury are too close to the Sun to be seen.
You might have seen a web page saying that Mars is going to be so close this year that you could practically reach out and touch it, or some such nonsense. Don't believe a word of it. Mars is actually quite a long way from Earth this month. That web page you read was written in 2003, when Mars really was close to Earth. For more on the topic, see our special Mars debunking page.
For a detailed list of things happening in the sky, click here.
Two Perseid meteors.
Pic: Robin Scagell
We have a whole section of the website devoted to the Moon and its features.
August is usually a great month for shooting stars – what astronomers call meteors. You can expect one every ten minutes or so on most nights, as long as you have a fairly dark sky. Around Tuesday, 12 August we get the annual Perseid meteors, which are one of the year's strongest showers, but this year the Moon is just after full and will make the sky rather too bright for us to get a good view. But it might be worth watching in any case, if it's is really clear.
The Perseids don't just appear in Perseus (which is shown on our map at the top) but can appear anywhere in the sky. They appear to come from the direction of Perseus in the northeast. You may hear that there could be 80 an hour visible, but don't take that too seriously. That's a theoretical number based on perfect conditions, which won't apply. You might see one every few minutes, though there are sometimes bursts of activity with a few in a single minute. The Moon will make them more difficult to see.
You can find out a lot more about what to do when you see one in our guide to observing meteors. And there's a 35-minute video from our Meteor Section Director telling you all you need to know about observing the Perseid meteors.