The universe has some very extreme places in it – and there are few places more extreme than the surface of a neutron star. These ultradense objects form after a supergiant star collapses into a sphere about 10 kilometers (6 miles) in diameter. Their surface is extreme because of the gravity, which is about a billion times stronger than Earth. However, that gravity also forces the stellar remnant to be extraordinarily flat. Just how flat is the outcome of a new set of theoretical research by PhD student Fabian Gittins from the University of Southampton.