The discovery of the new planet 2003 UB313 is one of the cooler pieces of science news so far this year. Assuming, of course, that it's eventually called a "planet" and not given some more boring designation. I'm with the leader of the discovery team, Mike Brown, who says that the word "planet" has a cultural meaning as well as a scientific meaning. The public hasn't taken kindly to suggestions that Pluto be downgraded from a planet to a Kuiper Belt Object; I don't either. I suppose I'm just being sentimental.
I also like the fact that the new planet is 45 degrees out of the plane of the ecliptic. I say it's about time we had a planet that wasn't so conformist and hide-bound. (And now that we know there are planets outside the plane of the nine, I'm betting we're going to find a bunch more of them.)
This is almost as good as the discovery earlier this year of a planet orbiting a three-star system. As an SF writer, I always found it annoying to hear scientific experts say, "Forget it—there won't be planets around binary and trinary star systems (except maybe Tatooine)—the orbits will be too unstable." To which my answer, under my breath was, "Oh yeah? We’ll see." Which is more or less my answer to the argument that we'll never find a practical means of interstellar travel. I consider it a challenge when I'm told something's impossible.
Click to read a very interesting article about the crazy business of naming solar system objects.