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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. Pluto is a very very distant object. Now, 10 years ago, we were taught about Pluto as being the most distant planet from the sun but that's not been the case since 2006 when it was downgraded to the status of dwarf planet. The reason for that is it's really too small to qualify. Although it's round which is the shape planets are, it's not big enough that its gravity can clear the material around it. So from now on, it looks like it's set to remain a dwarf planet. It's also an example of a planetary binary system as well because Pluto has a moon, Charon which is about half its size, so you have this weird situation where two objects orbit around each other rather than being the case you might imagine where a big planet has a much smaller moon going around. Now, we don't know a great deal about Pluto simply because it's so far away, it's very small, it's even smaller than the Earth's moon and it takes a very large telescope to show any detail at all and even the best ones in the world don't show all that much. But we do know that it's actually a bit like a comet. It's made of half rock and half ice and if it came in close to the sun, there's no reason it will but if it did, it will be an incredibly dramatic object with all that ice turned to gas and this vast hale coming of it. The best hope to know more about Pluto is the New Horizons Spacecraft. It's the only major object we haven't sent things to in the solar system and New Horizons was launched in 2005 but we'll get there in 2015 and in that year, we should learn a lot more about this really odd world right out of the edge of the solar system. .
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