Every atom in your body that's heavier than helium was forged inside a star — and most of those stars are long dead.
Stars are essentially gravity-compressed hydrogen fusion reactors. They turn light elements into heavier ones, generate the radiation that drives planetary climates, and — when massive enough — explode into supernovas that seed the universe with the heavy elements life needs.
Our Sun is one of an estimated 200 billion to 400 billion stars in the Milky Way alone, and the Milky Way is one of trillions of galaxies. The scale defeats intuition.
The verified facts below cover star birth, life cycles, neutron stars, supernovas, and the strange behaviors of stars that don't look like ours — including the ones that pulse, flicker, and occasionally swallow planets.
Below: every fact from our verified archive that touches this topic. Each is independently sourced; click through to its dedicated page.