spacetoday.net: Black holes predate galaxies

Black holes predate galaxies

Posted: Thu, Jan 8, 2009, 6:09 AM ET (1109 GMT)
Massive black holes found in the cores of galaxies were created before the galaxies themselves, astronomers reported this week. Previous research had indicated an nearly constant ratio between the masses of the central bulge of stars and gas in galaxies and the black holes at their cores, raising the question of whether the black hole formed after the galaxy did or if the galaxy formed around the black hole. New studies of the formation of the first galaxies in the first billion years after the Big Bang indicate that the black hole/bulge ratio is much larger, indicating that the black holes formed first. The mechanism that regulates the growth of the black holes and their galaxies has yet to be understood, astronomers said.