"Goofy's" discoverer on the impending IAU proposal

Dr. Michael Brown of Caltech, discoverer of 2003 UB313 ("Goofy;" three early photographs showing its movement against the stars are at the left) says that the definition of "planet" (and hence the resolution of the status of both Pluto and "Goofy") a committee of the International Astronomical Union appointed for the purpose will announce tomorrow will be voted on by the IAU next Tuesday, August 24.

He also gives a quite lucid summary of the reasons for the controversy, and the various things the IAU might decide to do about it. Interestingly, he gives my definition of a "planet" (any object with enough mass to be round, which is not a moon) the best chance of winning out, at about 40%. However, he also points out- and this, I did not realize- that if that is the definition that is adopted, we will go overnight from having nine planets to having 53! The asteroid Ceres- which was called a planet when it was discovered, but later demoted when other asteroids were discovered- would be included once again, along with all the known, round Kuiper Belt Objects, like Pluto and "Goofy." (Random thought: if Ceres becomes a planet again, would that make it "the world, Ceres?" I have no idea why a Cubs fan would ever think of that pun. Never mind).

It gets worse: Brown estimates that there are about 100 round Kuiper Belt Objects out there!

Brown gives the possibility that the IAU will reject whatever definition is proposed about a 30% chance- the same as simply keeping Pluto and defining "Goofy" as a planet, too, bringing the total to ten.

Brown sees about a 3% chance that Pluto will be demoted, and that we'll have only eight planets next week.

Least likely, according to Brown (about a 2% chance): keep Pluto, but reject "Goofy-" which, I have to agree, wouldn't make a great deal of sense.

What will the official name of "Goofy" end up being? And no- despite numerous reports to the contrary, it is not even informally named "Xena," which was nothing more than a joking code word among Brown's team of astronomers used in the same spirit in which another object discovered on Christmas Eve- 2003 EL61- was called "Santa," and its moon, "Rudolph !"

If the new definition includes it as a planet, it will have to be named, by IAU rules after a deity of the underworld in some pantheon or other. If, however, it ends up being a mere Kuiper Belt Object, it will be named after a deity of creation.

Stay tuned. We'll know what the committee has decided in a few hours- and we'll apparently have the final IAU decision within the week.