So scientists have found a 10th planet, sort of. This is actually going to increase pressure to go back to eight planets, because discovering a bunch of icy rocks about the size of Pluto way out in the Kuiper Belt–as seems likely over the next few decades–is going to make the astronomers give more thought to what it takes to classify an object orbiting the sun as a “planet.” This new object, currently called Sedna after an Inuit goddess, is a bit smaller than Pluto, but possibly big enough (like Pluto) to have a limited atmosphere. The major threat toward Pluto will come when somebody finds a Kuiper Belt object that’s just a little bigger.