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I'm Robert Massey and I'm here from the Royal Astronomical Society which is one of the biggest astronomical organizations in the world and we look after the interests of astronomers not just in the UK but across the world. What I'm going to do today is give you a few pointers to get you started in astronomy which I think is one of the most incredibly interesting subjects there is. One of the great things of an amateur astronomer can have is a good telescope like this one. With the telescope, what you're basically doing is making your eye a bit bigger. You're collecting more light from a bigger area and you're concentrating it into your eye and that's why, for example, it's very important never to look through a telescope at the sun because you'll probably blind yourself. But when we look at the night sky, whether we look at planets or so the moon or faint stars or clusters of stars or binary stars, all of these things, a telescope helps to see those more clearly and it does that because it collects more light and it means that we're able to see those objects sharper and we're also able to see fainter objects appear brighter than they would otherwise. And the way this telescope works, they all work more or less the same way, but it should depend on whether they use mirrors or lenses, but this one collects light here, comes down the tube, hits the mirror which you can't see so easily but there's a curve mirror in here that starts to bring the light to focus, goes back up the tube, hits another mirror here in these lens and then goes back down again, hits yet another mirror of 45 degrees and that sends it out the side. Now, that might look like an exotic or an unusual design but that's the way a lot of astronomic telescopes are put together, and the light comes out here and then we can examine it with the use of another lens called an eyepiece and that's basically the bit you look through. And if you change the eyepiece, you can get different magnifications. So, you simple look through it like this and then you enjoy the view. You can focus it. You can move the telescope around. Ideally, it'd be on a tripod and you can just therefore work outside with the most stability and point to the objects you wanted to and keep them there. Now, a telescope like this is really good for looking at many objects in the night sky but they are some of the familiar things like the moon or say, Jupiter and Saturn, and you'll see really good detail on all those objects. But it is important to look for one that's got a decent size lens or mirror because that's the key criterion for a telescope. You shouldn't worry about the manufacturer's claims of that magnification, that's much less important than how big the mirror or the lens that collects the light actually is, the key thing that governs how well a telescope works. .
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