Posted: Wed, Mar 14, 2001, 11:35 AM ET (1635 GMT)
New data from NASA's Chandra X-ray Observatory released Tuesday has shown that black holes were commonplace and active in the early universe. Two groups of astronomers took long exposures — totaling over 11 days each — of two regions of the sky, allowing them to detect faint, distant x-ray sources. The "Chandra Deep Field" observations, combined with data from Hubble and groundbased telescopes, revealed that there were at least 200 million supermassive black holes and even larger number of smaller black holes in the early universe, based on extrapolating the number of black holes found in these regions over the entire sky. The observations also show that black holes were "much more active in the past than at present," according to astronomer Riccardo Giacconi. The Chandra data also revealed a distant quasar, shrouded in a cloud of gas and dust some 12 billion light-years away, that may help astronomers understand how galaxies form.
