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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. Mars is the planet in the solar system that's most like the Earth. Now, that's not to say it's very like the Earth because as far as we know for the moment, although it's just possible, it doesn't seem to have any life on its surface. It's really, again, a rather harsh place to visit. It's very cold, just being that bit further out from the sun, not having much of an atmosphere means that it gets incredibly cold during the night and incredibly cold on the poles. It's so cold that carbon dioxide, the stuff you breathe out, freeze out on the surface. Now, Mars, though, has an interesting past. It's just possible that if you run the clock back to 3,000 million years ago, there might have been a lot of water on the surface and who knows it's possible that there was life there at that time. So, it is a really really good target for people to go and visit. It's not going to be easy but if we do get there, it offers one of the best chances of looking for life elsewhere in our solar system. Now, Mars can also be a slightly frustrating planet. Although it's about half the size of the Earth, most of the time, it's too far away for telescopes here to get a very good view of it. So, although you imagine you can see all these details on the surface, they're quite hard to spot. It's only perhaps every 15 or 17 years or so that it comes close enough to the Earth that you can get a really good view, and that's why the early astronomers that looked, they imagined all kinds of details because it's quite hard to spot things there even with large telescopes for that time, they imagined things like canals that simply didn't exist. But we do know that there are big canyons on the surface so whether planets cracked apart, there are ice caps, there are also frozen pieces of ice there as well and probably quite a lot of water under the surface. But all of these things have come with the space age. It took robotic probes going to Mars to find these things.
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