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Possible new planet discovered

The Hubble Telescope has photographed a possible 10th planet that was discovered at San Diego's Palomar Observatory. Photographs show that the object is virtually the same size as Pluto. KPBS reporter Beth Ford Roth has more.

Cal Tech professor Mike Brown discovered UB313 last year at Palomar and nicknamed the object "Xena." He says although there's been some rough measurements that showed Xena is bigger than Pluto, the Hubble telescope is the only way to accurately measure how big across the possible planet is. That's because Hubble orbits earth.

Brown: "Everything on the ground is so affected by the earth's atmosphere that when we try and look at the disc, we just see a big smeared thing that we can't measure the size of, but up in space we can very precisely measure the size."

The new measurements show Xena is just about the same size as Pluto only about five percent larger. Brown says he's pleased his discovery is almost a twin of Pluto. He says that means either Xena will be designated a new planet, or Pluto will be demoted from its planet status.

Beth Ford Roth, KPBS news.

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