Wednesday, August 16, 2006

PS About Planets : Mercury Venus Earth Mars Ceres

The International Astronomical Union is about to change the official definition of 'planet' to, basically, what orbits the sun and is big enough that its gravity makes it round. If adopted by the convocation on August 24th, this definition would embrace Pluto and also Ceres, Charon, and Xena (2003 UB313), bring the current count up to 12, and raise the possibility of still more planets being added to the list as we explore the further reaches of the solar system.

Read about it at SpaceWeather.com today, and note also the dynamite sunspot photo...

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