Scientists have spent centuries studying how matter works. They’ve boiled it, they’ve frozen it, and they’ve even thrown it into particle colliders and smashed it up. They’ve learned a lot about what matter does in these conditions, but--that’s just what we can do on Earth. “A neutron star is basically the densest object aside from a black hole. When they collide, the matter itself is deformed in such a way that we can probe densities inaccessible to laboratories on Earth,” Leslie Wade said.