Naming the Plutoids


The solar system has a new dwarf planet: Makemake, which is the fourth dwarf planet in the system (after Ceres, Eris and Pluto) and the third “plutoid” (a sub-definition which at this point can basically be defined as “all dwarf planets in the solar system but Ceres”). Co-discoverer Mike Brown, who also co-discovered Eris and thus is partially responsible for Pluto’s demotion, fills us in on the particulars of this new little world:

Its orbit is not particularly strange, but it is big. Probably about 2/3 the size of Pluto. And it is bright. It is the brightest object in the Kuiper belt other than Pluto itself.

The Mike Brown blog link I’ve just pointed you to, incidentally, is fascinating because it describes in some detail how Brown came up with the name “Makemake” — which is the name of a Polynesian fertility god — for his discovery. It has something to do with the date the plutoid was discovered, which was a few days after Easter. Reading Brown’s description of the naming process, it comes across a bit like a Rube Goldberg process. One also suspects that given how immensely large the Kuiper Belt is, and how many plutoids are waiting to be discovered out there, that sooner or later even the most obscure gods will have themselves a plutoid of their own. No offense to Makemake, who I’m sure is an awesome god. Please don’t smite me, Makemake.

As an aside to this, but somewhat more than tangentially related, allow me to air my opinion that sooner or later (and probably sooner than later) the International Astronomical Union is going to be sorry that it saddled Pluto, Eris, et al with the title “dwarf planet” since I think it’s only a matter of time before someone finds a dwarf planet with a larger estimated diameter than Mercury (which, since Mercury has a diameter of merely 3000 miles, shouldn’t be that hard to do), and then we’ll be in the embarrassing position of having a “dwarf” planet outsizing a regular planet, and then what do we do? The answer is that the Pluto partisans will have a hearty laugh at the IAU’s expense, and then we’ll watch as the world’s astronomers squirm and try to find yet another definition for all those troublesome icy planets past Neptune, and the textbook industry claps in delight as another run of science texts finds its way into the classrooms.

Yes, that’s right: This is all really just a conspiracy to prop up the high-school science textbook market. Discuss this amongst yourselves. But be assured: Makemake will smite them all for their sins, He will. As well He should.

(Art credit: NASA/STScI. Nicked from here.)



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