I was one of the guests on a special episode of The Naked Scientists dedicated to Pluto, everyone's favourite dwarf planet. In my section of the podcast I showed host Graihagh Jackson the historic Northumberland Telescope at the Institute of Astronomy. It's a fun little telescope—well, not really "little"!—that has the great claim to fame of being used to nearly discover Neptune when John Couch Adams was an undergraduate here. As it's a refracting telescope, it has a honking great lens in it, so it is quite imposing and a lot of fun to show to people who visit the Institute. In particular it has a really big observer's chair that slides up and down and rolls around the room. Oh, how astronomy has changed since then! For the better, of course. It must have been freezing to observe in the middle of winter in that thing.
We also spoke about the difficulty of seeing things that are very faint and far away, the Kuiper belt and where it comes from, and why comets may provide us a link to what the solar system was like at a young age. You can hear the whole show here: "Pluto, at Long Last".