The latest example of why forming international committees is a really, really bad idea comes from the International Astronomical Union, which is creating a massive muckup of UN proportions.

Ever since Pluto was discovered there have been debates about whether it is really a planet or not (our moon is 1.5 times Pluto’s size). So a committee of seven people from around the world have taken the last two years in coming up with a new definition of a planet.

It’s a doozy. It’s going to change everything. Are you ready to hear this earth-shattering galaxy-shattering new concept? Brace yourself, ’cause here it comes:

A planet is something that is round, orbits a sun, and isn’t itself a sun nor a moon.

Honestly. That’s it. Two years of work.

Owen Gingerich (of Haar-vaard, don’cha know), who chairs the Planet Definition Committee (which consists of — get ready for this — “astronomers, writers and historians” — honest!), said:

In July we had vigorous discussions of both the scientific and the cultural/historical issues, and on the second morning several members admitted that they had not slept well, worrying that we would not be able to reach a consensus. But by the end of a long day, the miracle had happened: we had reached a unanimous agreement.

And he’s right, it is truly a miracle that seven otherwise intelligent people can unanimously agree that this is a good idea. (I think that using writers and historians to come up with scientific terminology must have been the key).

Because, you see, this simplistic definition has problems. It immediately adds three planets to the solar system — the asteroid Ceres (580 miles in diameter, about the size of Texas), Pluto’s moon Charon, and 2003 UB313 (aka Xena, a “planet” bigger than Pluto but so far out that it was only recently discovered).

Ah, clever reader! You noticed that I slipped in a moon (Charon) but the definition says the object has to orbit the sun, not another planet, didn’t you? That’s because the center of Pluto/Charon rotation (or barycenter) does not occur within either body – it’s in between. So Pluto and Charon are to be defined as a binary planetary system.

Of course, under this definition Earth’s moon (which each year drifts out about an inch and a half) will one day be far enough away from the Earth that it too will qualify as a planet (in a few billion years or so, assuming ol’ Sol doesn’t go red giant on us).  That seems pretty arbitrary to me.

But for now the order of the “planets” becomes: Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Charon, UB313.

Frustrated schoolchildren will have to come up with new mnemonics to remember the planets; old favorites like “My Very Erotic Mate Joyfully Satisfies Unusual Needs Passionately” just won’t do any more. 

In honor of this latest muckup, I propose: Mostly Vacuous Education Makes Cretins Jumble Science Until Normal People Can’t Understand. What do you think?

But wait, there’s more! Because anything over 450 miles in diameter of sufficient density and rotation will have enough gravitational pull to eventually pull itself into a fairly round shape, there are over fifty other rocks running around the sun that could also qualify as planets! As a matter of fact there are already dozen “candidate planets” on the IAUs “watchlist”.

Rocks like Quaoar, nearly the size of Pluto and the home of volcanic activity. Not to mention Ixion, 2002 UX25, Varuna, 2002 TX3000, 2002 AW197, 2004 DW, 2001 KX76 and Sedna – all denizens of the Kuiper Belt. These bodies are all called Kuiper Belt Objects, or KBOs. And beyond the Kuiper Belt lies the Oort Cloud which consists of even more rocks, some of which may be rather large leading to even more “planets”.

Some estimate that there could be upwards of 50 rocks out there that could be classified as planets under the new definition. In fact, Mike Brown (the astronomer that led the team that discovered 2003 UB313) wryly calls the proposed definition “leave no ice ball behind“.

Heh. An astronomer with a sense of humor!

So now that the Planetary Definition guys have thoroughly mucked things up, they have to try and make things a little simpler. We can’t have 50 or so planets, can we?

Well actually, according to them, yes we can. But to make it easy on the kids they’ve decided to create an entirely new class of planets called “plutons”.

Plutons are Trans-Neptunian Objects (TNOs): anything that orbits further out than Neptune. To get an idea of just how far out these bodies are, check out this simulated flyby movie of all the “new planets” from Mercury to UB313, hosted on New Scientist.

By removing plutons from consideration we are left with the eight “classical planets” (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune) plus Ceres in the asteroid belt between Mars and Jupiter.

Viola! Once again we have nine planets. So what if one of them is a lifeless asteroid on steroids? “Science” is satisfied.

Astronomy professor David Jewitt has an excellent commentary on this muckup:

Unfortunately, the IAU committee is stuck between a rock and hard place. The public assumes that there should be a tight definition of what makes a planet and further assumes that the IAU has the responsibility to make that definition.

The public also seems attached to the planet label for Pluto, which limits the range of options open to the IAU (given that they would not want to make a definition which brings public scorn upon them). At the same time, the IAU is a science organization, and they don’t want to do anything too crazy (I assume) in the eyes of astronomers.

The result is the compromised, lawyerly language of the IAU proposal. I feel their pain…there is no good answer to “what defines a planet?” and yet they have been asked to make such a definition. Their big mistake was to agree to do so.

Unfortunately, this won’t be the last time we’ll need a Planetary Definition Committee: CS Monitor notes that the new definition addresses the lower end of the planetary scale, but does nothing about the upper end. Are brown dwarfs to be labeled planets? I should hope not!

Geologists are up in arms and writing angry letters. You see, “pluton” is already a scientific term assigned to subsurface igneous rock formations. The good news is that astrologers are unfazed over the possibility of adding three
planets, so your horoscope can still be accurately cast each day.

Technorati tags: International Astronomical Union, IAU, Planet Definition Committee, Astronomy, Owen Gingerich, Planets, Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Charon, 2003 UB313, Quaoar, Ixion, 2002 UX25, Varuna, 2002 TX3000, 2002 AW197, 2004 DW, 2001 KX76, Sedna, Kuiper Belt, Kuiper Belt Objects, Oort Cloud, Plutons, Trans-Neptunian Objects, David Jewitt, Brown Dwarfs, Astrology, International Idiocy.