Discovery of a New Planet in the Outer Solar System

A team of researchers from the California Institute of Technology in Pasadena, Calif., Yale University in New Haven, Conn., and Gemini Observatory on Mauna Kea, Hawaii, report the discovery of a new planet in the outer solar system. Officially designated 2003 UB313, the new planet is intrinsically brighter than Pluto and three times farther away. Assuming the reflectivity of the surface is the same as Pluto’s, it is the largest object detected in the solar system since the discovery of Neptune and its moon Triton in 1846.