Two NASA telescopes used to understand first documented supernova
(NEWSER) - It's one of astronomy's oldest mysteries—Chinese astronomers in AD 185 discovered a "guest star" that appeared in the sky for about eight months. Modern scientists have for decades believed it to be the first documented sighting of a supernova, but what kind of supernova was it? At long last, astronomers know. The ancient astral explosion was in fact a Type Ia supernova—a star about the same size as our sun that shriveled into a white dwarf, then emptied all the matter around it in space, siphoned off a nearby star, and exploded in an unusually large and rapid nova, reports Space.com . More»