A new observing instrument VIRUS-W saw
Astronomers have discovered 16 close-knit pairs of supermassive black holes in merging galaxies. These black-hole pairs, also called binaries, are about a hundred to a thousand times closer together than most that have been observed before, providing astronomers a glimpse into how these behemoths and their host galaxies merge -- a crucial part of understanding the evolution of the universe.
Galaxy X: An entire galaxy—made mainly of dark matter—may be lurking just outside our own, scientists say.
NASA's Fermi Gamma-ray Space Telescope unveiled a previously unseen structure centered on the Milky Way. The feature spans 50,000 light-years.
