A quasar is an active supermassive black hole. Scientists think they manage this feat by sucking hydrogen fuel away from companion stars.Īrtist's concept of a dusty torus, or donut, of accreting material fueling a quasar. They burn much hotter, for example, and appear much bluer. These vampire stars are known as ' blue stragglers,' and they act much younger than the ancient neighbors with which they formed. Just like vampires of fiction, some stars manage to stay young by sucking the life force from hapless victims. They can roar back to life, albeit briefly, in a gigantic supernova explosion by sucking material from their companion stars, or by merging with them. White dwarfs are 'dead,' but they don't have to stay that way in a binary system. Type Ia supernovas explode from binary systems that contain at least one white dwarf - a tiny, super-dense star that has ceased undergoing nuclear fusion reactions. Some stars do Fomalhaut b one better, literally coming back to life in violent and dramatic fashion.Īstronomers know these zombie stars as Type Ia supernovas - huge and powerful explosions that send star innards streaking out into the universe. In this artist's conception, a supernova explosion is about to obliterate an orbiting Saturn-like planet.

Thousands of these 'time bombs' could be scattered throughout our galaxy. New research shows that some old stars known as white dwarfs might be held up by their rapid spins, and when they slow down, they explode as Type Ia supernovas.

Scariest astronomical phenomena