nebulae

Every atom of iron in your blood was forged inside a dying star. Here's the full life cycle that made you possible.

Nebulae are vast clouds of gas and dust between stars. Some are stellar nurseries where new stars form, some are shells shed by dying stars, and some are the debris of supernova explosions. The Orion Nebula is a nursery visible to the naked eye; the Crab Nebula is the expanding wreckage of a star that exploded in 1054.