Imagine the Sun squeezed down to the size of a city.
Imagine the Sun squeezed down to the size of a city. That is a neutron star — a sphere roughly 20 kilometres across, yet packing more mass than our entire Sun. The numbers get stranger from there. A single teaspoon of its material would weigh about a billion tonnes on Earth. Not a mountain's worth — a billion tonnes from one small spoonful. Neutron stars are born violent, forming when a massive star exhausts its fuel and collapses in a supernova explosion, crushing its core to almost unimaginable density. Surface gravity runs billions of times stronger than what keeps you in your chair right now. And some of them spin hundreds of times every second, sweeping beams of radiation across space like a cosmic lighthouse — those are pulsars. The universe builds things we can barely calculate. Follow Deep Field Vault for more.