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What's Up for May 2015

The sky is dark, the stars are gleaming – time for some astronomy. But wait a minute. I don't recognise any of them. Where are Orion and the Plough? I'm lost.

If this means you, read on. We can tell you how to spot the stars, pick out the planets, get to grips with the galaxies... OK that's enough alliteration. But you get the idea.

Now then, young stargazers. It may be May but it can still get cold at night, so put your coat on. Don't worry, no-one can see you and pretend they aren't cold at all even though they are only wearing a T-shirt. You can wear a baseball cap as well if you really want to, but take it from us, they are pretty useless when you want to look through a telescope as the peak gets in the way of the eyepiece. And if you turn it round it falls off when you crouch down. So take a tip and go for the good old bobble hat.

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:

Whole sky for May 2015

All maps produced using Stellarium software.

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.

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 May at about 11 pm, at the start of the month at 12 pm, or by the end of the month at 10 pm, though at this time of year the sky is too light to see much at that time. That's why we have had to make the time so late. All times are BST (British Summer Time, but they work more or less OK in other parts of the northern hemisphere).

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

Making sense of the stars

If it all looks just like a lot of dots, and drives you dotty, here's the way to get to grips with the sky. Start with something familiar and work from there. Most people recognise the seven stars that in the UK we call the Plough and in the US is called the Big Dipper but which is really Ursa Major, the Great Bear. If you can't find it, it's because you aren't looking high enough – it's almost above your head at this time of year, so it's shown at the centre of this map.

Look below the Plough, about halfway between there and the horizon, and you will see a group of stars called Leo. 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.

Sky for May 2015

Other constellations to look for

Lower down and to the left of Leo is Virgo with its bright star Spica and Mars in the middle of Virgo. Another way to find Spica is to go up to the Plough and follow the curve of its handle round. First you come to a very bright star, Arcturus, and then you come to Spica, which is a lot lower in the sky. On the map is marked a sort of Y shape, which is quite easy to pick out, which helps you to spot Virgo. Virgo is full of faint galaxies, and if you have good binoculars and a fairly dark sky and want a challenge, follow the link to find out just where they are.  For a map with all the constellation names on it, click here.

An easier target is the constellation of Coma Berenices. This contains a very nice and large star cluster which you can see by eye in good skies, or using binoculars if your skies are lousy like most of us have to put up with. It's to the left of Leo, and above Virgo. Follow the link to find more objects you can look for.

This month’s bright planets

There are three bright planets on show in the evening sky at the moment, and four if you count Mercury which sets just after the Sun at the beginning of the month so it has set by the time our maps show.

Mercury as it appears on 2 May (top) and Venus as it appears on 15 May (above).These views show north at the top, so astronomical telescopes will show them the other way up.

The most obvious is Venus, shining very brightly in the western sky after sunset. If your friends know that you are an astronomy geek, they are bound to ask you what it is, so make sure you see it before they ask. Right now it is approaching Earth, and getting larger as it does so, and looking like a fat half Moon.

Jupiter is still with us, quite high up over in the south-west. Through binoculars you will see up to four of its bright moons, on either side. A telescope will show you dark belts, and if you're lucky you may see the Great Red Spot, though it isn't particularly prominent through a small telescope.

 Saturn is low down in the eastern sky, in Libra. It is better visible later in the night than the time of our map, but it never gets very high in the sky at the moment. Next year and for a few years to come it will be even lower down as seen from the UK, so take a look at it now through a telescope if you can. In recent years the rings have been more or less edge-on to us, but now they are opening out again and look great. And you don't need a super-colossal telescope to see them – any reasonably good small telescope should show them using a magnification of 50 or more. If it doesn't, it isn't (reasonably good, that is).

Finally,  Mercury. Some people say it's hard to find, but you just have to look at the right time. The first half of this month is one such time, and you will see it if you look to the north-west about 45 minutes after sunset. It looks like a bright star in the twilight, and will be visible from the beginning of May until the end of the month. It appears less than half the size of Venus but with a good telescope you might see it looking like a tiny half moon about 2 May. It is at its farthest from the Sun on 7 May, by which time it is already starting to become a bit crescent-like.

Mars is too close to the Sun to be seen easily at the moment.

Don't forget the Moon

It begins the month getting close to full Moon, which is on the 3rd. At this time and for a few days before and after its light drowns out the fainter stars and other objects. Next comes last quarter on the 11th. We have new Moon on the 18th, and first quarter (half Moon) is on the 25th.
We have a whole section of this site about the Moon and what to observe, so do take a look.

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