Hubble Finds 'Tenth Planet' -- Maybe

The question is, do astronomers add Xena as a tenth planet, or DROP PLUTO as a planet because it’s part of the Kuiper Belt? Personally, if the Kuiper Belt is orbiting Neptune, that strikes me as more reasonably considered a very complex kind of moon system; but then, that’s probably why nobody is asking me how to handle this one. :)

“The Kuiper Belt is a vast ring of primordial icy comets and larger bodies (including Pluto and Xena) encircling Neptune’s orbit. Finding that the largest known Kuiper Belt object is a virtual twin to Pluto may only further complicate the debate about whether to categorize the large icy worlds that populate the belt as planets. If Pluto were considered to be the minimum size for a planet, then Xena would fulfill this criterion, too. In time, the International Astronomical Union will designate the official name.” NASA - Hubble Finds ‘Tenth Planet’ Slightly Larger Than Pluto