LOS ANGELES - Scientists say they have confirmed that a so-called 10th planet discovered last year is bigger than Pluto, but that likely won't quell the debate over what makes a planet. The astronomers who spotted the icy, rocky body — informally called UB313 — had reported only a rough estimate of its size based on its brightness. But another group of researchers has come up with what is believed to be the first calculation of UB313's diameter. By measuring how much heat it radiates, German scientists led by Frank Bertoldi of the University of Bonn estimated that UB313 was...