spacetoday.net: Large planetoid discovered beyond Pluto

Posted: Fri, Feb 20, 2004, 9:46 AM ET (1446 GMT)
Astronomers announced Thursday that they have discovered a large Kuiper Belt object (KBO) beyond the orbit of Pluto that may be half the diameter of that most distant planet. The object, 2004 DW, was discovered this month by Caltech astronomers at Palomar Observatory; the discovery has been confirmed by European astronomers using a telescope in Spain. The object is in a similar orbit to Pluto, but over two billion kilometers farther away from the Sun than Pluto. Based on the object's brightness and distance, astronomers estimate 2004 DW could be as much as 1600 kilometers in diameter, more than half the size of Pluto, 2300 km across, and larger than the previous largest KBO, 1250-kilometer Quaoar.