I am certain that there are a number of elementary school teachers in the same situation I am in: I have spent the past four days getting my classroom ready for the beginning of the school year, and now I have to start all over. Why? Because some oh-so-clever astronomers got it into their heads to reclassify Pluto. It used to be that the question was not "What is Pluto," since we all knew the answer. Pluto is Mickey Mouse's dog. Goofy was the question mark.
Well, not anymore. Pluto is now classified as belonging to the much less exclusive club of "dwarf planet." Experts say there could be dozens of dwarf planets catalogued across the solar system in the next few years. Pluto doesn't make the grade under the new rules for a planet: "a celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a ... nearly round shape, and has cleared the neighborhood around its orbit."
So, how could this possibly impact the past four days of my life? I've got a shelf full of science textbooks that are now out of date. I know that I can create some fascinating banter with fourth graders about the shape and size and what constitutes a planet, but I'm going to have to learn it myself. And I'll have to add it to the exceptions to the things that they have all spent years learning just so we can tell them that "gh" really sounds like "f." And then there's classroom management. Some teachers use alphabetical order to run things. Others prefer to use students' lunch numbers to keep things orderly. I had foolishly believed that I might utilize some groupings based on the nine planets. "My Very Educated Mother Just Served Us Nine Pizzas." This was the mnemonic device I learned in some prior age for remembering the order of the planets - back when Pluto was part of the club. I suppose I could just go back to having eight groups, and I suspect that I will get around to creating some new, clever way to keep track of the sufficiently massive, self-gravitational, nearly-round, neighborhood cleared orbit objects in the solar system.
Finally, if you can't work up any sympathy for me on this matter, consider the fate of "New Horizons," a spacecraft launched this year to examine Pluto. From the New Horizon web page: "Under proposed International Astronomical Union definitions, two planets that orbit each other around a barycenter (or center of mass) between them are a binary planet. Those same definitions would expand the "family" of planets to include Charon, promoting Pluto's large companion from moon to planet and securing the pair's status as the first and (so far) only binary planet in the solar system." Somebody should have given the guys at NASA a little heads-up as to what was coming about this whole planet-definition thing. New Horizon isn't expected to reach the newly christened "dwarf planet" until 2015. Do you suppose by then that anybody will care? If we had to lose a planet, why couldn't it be the one that makes everybody nervous to say? Go ahead - you know which one I mean.