The Hubble Space Telescope has photographed the eerie, green-glowing gas highlighted by a recently deceased quasar.
The Milky-Way-sized object, located about 730 million light-years away, surrounds a supermassive black hole that was once the heart of a galaxy.
The black hole gobbled up its last available meal of gas and dust as a quasar between 45,000 and 70,000 years ago, ionizing oxygen in distant gas clouds into a bright green glow before fading back into darkness. The glowing gas cloud, known as Hanny
The Milky-Way-sized object, located about 730 million light-years away, surrounds a supermassive black hole that was once the heart of a galaxy.
The black hole gobbled up its last available meal of gas and dust as a quasar between 45,000 and 70,000 years ago, ionizing oxygen in distant gas clouds into a bright green glow before fading back into darkness. The glowing gas cloud, known as Hanny