Posted: Thu, Jul 5, 2001, 3:11 PM ET (1911 GMT)
Astronomers announced earlier this week that they have discovered an object in the distant Kuiper Belt that could be larger than Pluto's moon, Charon. The object, provisionally named 2001 KX76, was discovered in images taken in May from a four-meter telescope in Chile. The object is the brightest known Kuiper Belt object (KBO). Using estimates for the object's reflectivity, this brightness corresponds to a diameter between 960 and 1,270 kilometers. By comparison, Charon is 1,200 km across and Ceres, the largest asteroid, is 932 km in diameter. This discovery may fuel the debate over how to classify Pluto, the smallest planet: as the gap between the sizes of the largest KBOs and Pluto (2,275 km across) shrinks, some astronomers have argued that Pluto should either be jointly classified as a planet and KBO, or be stripped of planet status altogether.

Related Links:

•  NOAO press release
•  Spaceflight Now article