What is a planet? For years, astronomers have been debating that question, with the status of tiny Pluto hanging in the balance. Finally, an answer is in the offing. Today, the International Astronomical Union's Planet Definition Committee announced their proposal for a new, official definition of "planet." If the proposal is approved by a vote of IAU astronomers on August 24th, the number of planets in the Solar System would swell from nine to twelve. And, yes, Pluto would be among them. Get the full story at http://spaceweather.com .