A few years ago, Neil was excited to find out that our solar system might have a new planet. Orbiting the earth, sometimes closer in and sometimes further out than Pluto, the new would-be planet was named Sedna. Since the name didn’t come out of Hamilton’s Mythology like the rest of the planets’ names, I was like an addled parent trying to remember the unusual ethnic name of a new playmate. “What’s the name of that new planet again?” I had to keep asking Neil, until I had finally “got” Sedna as an Inuit goddess name.
Meanwhile, though Sedna had thrown Pluto’s status into question. Sedna was so small, the astronomers wondered if it should be classified as a planet at all. It wasn’t even big enough to orbit the sun in a regular way. But Pluto was just about the same size, as far as they could tell, and Pluto had an erratic orbit, too. In short, if we kept calling Pluto a planet, it was only fair to call Sedna a planet, too. And in doing so, we ought well reconsider all the other big rocks orbiting the sun at that distance, too. I’m not an astronmer, but I bet it was a hot topic at many an astronomical conference.
Surprisingly quickly, the astronomers concurred last year that Pluto was not a planet any more. Unfortunately, the information still doesn’t seem to have trickled into any educational materials. I suppose I can’t realistically expect it to: I think when I was learning about the solar system, the materials were just getting around to mentioning Pluto–and that was 50 years after its discovery. But it was still somewhat distressing to go to Chabot, an astronomy education center, and still find Pluto noted as the ninth planet repeatedly and on every single educational resource, from books, to pillars, to maps, to movies. And if Chabot hasn’t updated its information, when, if ever, will school textbooks, or the teachers themselves, do so?
So Sedna punked Pluto out of its planetary status, but if no one knows, does it still count?