SCIENCE IN THE NEWS DAILY
Do Solo Black Holes Roam the Universe?
from ScienceNOW Daily News
Even gravitational monsters can get the heave-ho. Two mysterious bright spots in a disheveled, distant galaxy suggest that astronomers have found the best evidence yet for a supermassive black hole being shoved out of its home.
If confirmed, the finding would verify Einstein's theory of general relativity in a region of intense gravity not previously tested. The results would also suggest that some giant black holes roam the universe as invisible free floaters, flung from the galaxies in which they coalesced. Although loner black holes may be an entity that has to be reckoned with, they would still be rare, notes theorist Laura Blecha of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
Blecha, along with observational astronomer Francesca Civano of Harvard-Smithsonian and their colleagues took detailed x-ray observations of the distant galaxy CID-42, nearly 4 billion light-years from Earth. The team focused on the region after a Hubble Space Telescope survey revealed two compact visible-light sources within the starlit body: one of them at or near the galaxy's center, the other offset from the core. Because CID-42 appears to be the remnant of two giant galaxies that collided relatively recently, it seemed likely that one or both of the compact sources were supermassive black holes.