Although it was recognized as a planet for decades, Pluto is much smaller than the other planets in our solar system and more closely resembles a giant comet nucleus. Consequently, the International Astronomical Union demoted Pluto to the category of dwarf planet, which reflected astronomers' conclusion that it is a member of the Kuiper belt, a strip of billions of icy bodies orbiting the Sun beyond the orbit of Neptune. What objects in the outer region of the solar system exceed Pluto in size? Discuss (http://forum.thefreedictionary.com/postst18332_Pluto-Gets-Demoted--2006-.aspx)
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