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Local professor’s planet-like discovery is larger than Pluto

German astrophysicists have measured the planet-like object discovered last year at Palomar Observatory and they say it's bigger than Pluto. Professor Mike Brown of the California Institute of Technology discovered the possible planet, called UB313, almost exactly a year ago. KPBS reporter Beth Ford Roth has more.

A group of astrophysicists from the University of Bonn and the Max Planck Institute have now measured Professor Brown's discovery, and they say it's the largest object found in our solar system since Neptune was discovered in 1846. Brown says he always suspected UB313 was bigger than Pluto.

Brown: In many people's minds I think this confirmation of the size will probably solidify the idea that this thing should certainly be called a planet if Pluto is called a planet, and that's really the big question, are you going to call Pluto a planet or not, if yes, then now that we know this thing's bigger, probably you should call this one too.

Brown says the International Astronomical Union will meet this summer to figure out what criteria should be used to determine if UB313 is a planet. Beth Ford Roth, KPBS News.

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