Pluto: And then there were eight
 

Pluto has been demoted.The celestial body, long known as one of the nine planets of the solar system, will now be considered a "dwarf planet," the General Assembly of the 2006 International Astronomical Union ruled in a vote Thursday in Prague, Czech Republic.Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune will be defined as "classical planets."Three other bodies had been contending for planetary status as well: Ceres, the largest-known asteroid; "Xena," the nickname for 2003 UB313; and Charon, which has been considered Pluto's moon. Ceres and "Xena" will now share "dwarf planet" status with Pluto. Charon, it has been concluded, will be grouped with "small solar-system bodies."The IAU said in a statement on Thursday that the definition for planet is now officially "a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape and (c) has cleared the neighborhood around its orbit." View: Full Article @ CNET News.com View: Neowin Forum Discussion Read full story...



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