Welcome, Ceres!

I, for one, am delighted at the IAU's proposed definition of a planet: something round that orbits a star but is not a star or a satellite. It's a good definition because it relies on physics (i.e. gravity) to define what a planet is, while keeping everything that is currently a planet a planet. Plus it actually adds some new planets, including Ceres, which has always struck me as more planety than asteroidy and is cool because it's right in the middle of the solar system. Pluto is still a planet, and not only that, it now becomes part of the possibly most exotic arrangement possible: along with Charon, it's a double planet! All those Pluto-haters who wanted it demoted to a "Kuiper Belt Object" must be fuming. Finally, with this new definition there are a dozen or so candidates for new planets, so the list will continue to grow. Exciting!


This redefinition of the term planet could be the best thing to happen to Astronomy in a long time: it gives the field a sense of being dynamic and changing, which it is anyway, but something like this might get some more people interested in the subject.

Update: But, of course, this didn't happen and Pluto's now been demoted to a 'dwarf planet' or somesuch. Pity.