This week is a very special, edition of the Naked Scientists as we dedicate a whole hour to the world's favourite dwarf planet - Pluto. But how did it get there in the first place? What has the New Horizons probe uncovered? And what's beyond Pluto? Graihagh Jackson puts the mission under the microscope, talking some of the leading scientists from the New Horizons operation and taking a trip to the edge of our solar system...