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Pluto is a Dwarf Planet

The semantic demotion of the Kuiper Belt Object Pluto to "dwarf planet" is a proper step to a clearer categorization of Solar System bodies. While it may still be loosely termed a planet for its orbit around the Sun, Pluto is too small and gravitationally uninfluential to be classed among the major terrestrial planets and gas giants. The continuing discovery of other similar KBOs of comparable size and composition makes it clear that we must redefine "planet" more specifically, lest our children face hundreds of "planets" to memorize in the future. We stand behind the measure of removing Pluto from the roster of major planets, but continue to appreciate that Pluto remains chief among large Kuiper Belt Objects as the first of these discovered by a human.

Read "The Case for Demoting Pluto" for more information in simple layman's terms, check our weblog for the latest news, see our FAQ page for responses to common concerns, and put a button on your website to express your solidarity with the demotion of Pluto. Leave a comment in the feedback section if you've got something to say.

"After all, it's not a great idea to let cultural attachments dictate scientific categories." - Michael Brown, NY Times editorial, 16 Aug 2006