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	Frequently Asked Questions Send to a friend  Printable version  En Español Keywords Solar System  Astronomers  Pluto  Discovery of Planets and Moons  Resources FAQs about The Solar System Solar System Guide Astronomy Gift Shop 2009 Sky Almanac McDonald Observatory logo cap Is there a tenth planet in our solar system?  No. On August 23, 2006, the International Astronomical Union decided that the solar system contains only eight planets. Pluto, which since 1930 had been classified as the ninth planet, was dropped from the list. More information Other FAQs Select FAQ category Earth, Moon, and the Sun The Solar System Space Probes and Human Exploration Stars and Nebulae Astronomers and Observatories Galaxies and Cosmology Stargazing and Star Lore » FAQs about StarDate Online The Solar System Links Center for Mars Exploration Solar System Exploration NASA's Mars Exploration Program Cassini Mission to Saturn Voyager Mission to the Outer Planets ESA Mars Express Messenger Mission to Mercury New Horizons to Pluto
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