Dummies_article

So much for what's up there and what it looks like. How do we go looking for it?

We look on a star chart, which now is more likely to be computer sofware than a book. And for the information that appears on them we have people like Charles Messier and Pierre Mechain, and William, Caroline and John Herschel to thank. They didn't know what M35, or Messier 35, at the top right of this view of Gemini was. Or NGC2392, the Eskimo Nebula, close to the yellow dot showing the position of Saturn that night. They discovered them, and compiled the Messier Catalogue, which dates from the eighteenth century, and the General Catalogue of Nebulae, which was rewritten into the New General Catalogue of Nebulae, or NGC, in 1888. And now all we have to do is hit a few keys on a computer and we can find out what's visible from our observing site and when, where it is and how big and bright it is, so we can work out which bit of equipment we'll need to look at it. You can even buy a telescope which will point itself straight at it so you don't even have to know where to find it. Personally I think that spending an hour looking for a galaxy in Virgo, then wondering if the one I've found is actually the one I was looking for, is more fun. Computer guidance, or the 'go to' facility, does have its place, but I wouldn't recommend it to a beginner. The important thing to remember is that finding things for yourself isn't daunting. To use a star chart you don't have to know every constellation. If you can recognise the brighter stars of just a few, you can use them to find anything else.

So let's consider what we need to look at all these lovely planets and galaxies and clusters and nebulae.

Number One - Somewhere to look from, though perhaps not here!

Try to find somewhere reasonably dark but don't choose somewhere fifty miles from home unless you live in the middle of London and have no choice. You'll only end up staying home. Hills attract cloud, unless you live in a desert, and rivers attract mist. If you can do your observing from your own garden so much the better, and don't forget that you can use buildings, fences and trees to screen lights. A lot depends on the type of observing you want to do. I can use binoculars from my garden by sitting in a chair and using some convenient sheds to hide street lights. To use a telescope I have to pack up and move out of the village, using a barn to shield lights from a road junction. For astrophotography I leave the country!

The bad and the good

One thing it's almost impossible to get away from, anywhere, is skyglow.This is the halo of light you see above towns and comes from all the light from inefficient street lights, pretty globe lighting so favoured in supermarket car parks, badly positioned security lighting and sports field lights ending up in the sky instead of on the ground where it's needed. What astronomers need is full cut off lighting - the type which is shielded to throw all its light downwards. It's still no good if you're underneath it, but it cuts sky glow completely. A lot of new motorway lighting is full cut off, and the transition from a stretch of old lights - lots of sky glow, indifferent light hardly reaching across the carriageways - to new lighting - a well lit road with pitch blackness above - is remarkable. You'll know it if you've seen it. All new lighting should be full cut off - it's not only good for astronomers, it's environmentally friendly too - but sadly it isn't.

Wherever you go, whether it's a drive out of town or to the bottom of your garden, you'll need to take with you finder charts for what you want to look at, a red torch to read them by - white light will simply destroy your dark adaption - a means of making notes and warm clothing. And don't stay out too long. Go home while you're still warm and awake. There'll still be things to look at on the next clear night.

Number Two - an eye......like these would be nice!

Learn to see faint objects and detail by using the rods in your eye - the low light sensors - instead of the cones which are your daylight sensors. It's called averted vision and all you have to do it look very slightly away from what you're looking at. After a while it becomes completely subconscious. If you've ever noticed you see things better in your peripheral vision at night, you've already been using averted vision.

Number Three - more magnification.....and one of these would be nice too!

Start with a good quality pair of binoculars. 10 or 12 by 50s are ideal. You need a reasonable objective lens size but you don't need huge magnification. That just adds weight, and even a fairly lightweight pair of binoculars can feel very heavy very quickly when you're looking up. If they're still uncomfortable use a deck chair or sun lounger. Use them to look at large objects like the Pleiades and the Andromeda Galaxy.

Then you might consider moving up to a telescope.

It has to be said that buying a telescope has never been easier, but when all's said and done there are still only a few manufacturers - all the multitude of shops sell the same range, so apart from accessibility if you don't want to buy mail order, and a small variation in price, there's little to choose between them. There are still, however, a lot of telescopes out there to choose from, and most of them are not cheap. You'd think that buying the right one for you should be easy.......