a starlike object that may send out radio waves and other forms of energy; many have large red shifts
"Astronomers detected a distant quasar with a massive red shift blasting powerful radio waves across the universe."
An extragalactic object, starlike in appearance, that is among the most luminous and (putatively) the most distant objects in the universe.
"Astronomers detected a powerful quasar billions of light-years away, confirming it as one of the brightest and most distant objects ever observed."