NPR reports that a IAU panel has unanimously recommended that Pluto (in the photo with its larger moon, Charon) keep its status as a planet, and it is possible that we may end up with several objects being recognised as new "dwarf planets".
I mentioned a while ago that the IAU was going to decide on an unambiguous definition for the word "planet", and that it was likely that this would change the number of planets in our solar system. The decision has not yet been reached; this should happen later this month. However, several members of the aforementioned panel suggest that Pluto will join a new group called "dwarf planets" (we already have "terrestrial planets" and "giant gas planets"), which might include any body that orbits the Sun and that is large enough that its own gravity makes it spherical (or nearly so); this would include anything larger than some 700km across.
This definition would include not only Pluto and Xena (a.k.a. 2006UB313), but also other smaller bodies such as Ceres (an asteroid between Mars and Jupiter). This would take the number of known planets to something like 13 or 14, but it is unsure whether this will be approved.
The IAU general assembly opens tomorrow, 12 August, in Prague.
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