When we shoot something into space, we leave stuff behind; that stuff becomes space junk. It's a real problem when we're trying to shoot more stuff into space and risk running into other stuff we shot into space. New solution: space harpoons! Al Jazeera explains: U.K. scientists want to build another satellite that can harpoon space debris and reel it down into the atmosphere, where it'll burn up. They're hoping to get the program started in the next few years. Great. We really need to get this situation figured out, because we've seen a lot of ideas (somanyideasso many) and we have about 6.5 tons of the junk floating around up there.