At the Edge of the Solar System: Icy New Worlds Unveiled

On August 24, 2006, the solar system lost its ninth planet! The astronomers' decision at the IAU General Assembly in Prague to demote Pluto had been precipitated by the discovery, beyond the orbit of Neptune, of a very rich population of Pluto-like objects. The study of the recently discovered remote celestial bodies grows ever more fascinating. Their great variety in color, shape, size, and orbit has astonished observers. What is more, studies of the composition of these new-found objects ...