Pluto aficionados, rejoice! Pluto is a planet. So are the giant asteroid Ceres, Pluto's moon Charon, and a large outer-solar system object called 2003 UB313. The solar system has 12 planets instead of the familiar 9, according to a proposal that the General Assembly of the International Astronomical Union (IAU) will vote on next week in Prague, Czech Republic.
Note: To comment, Science News subscribing members must now establish a separate login relationship with Disqus. Click the Disqus icon below, enter your e-mail and click “forgot password” to reset your password. You may also log into Disqus using Facebook, Twitter or Google.