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Astronomers at the Space Telescope Science Institute have new evidence for explaining the mysterious X-ray background that permeates the universe. Astronomers Antonella Fruscione, Richard Griffiths and John Mackenty have found a number of "star-burst" galaxies which could help to account for the X- ray background. This at least rivals the contribution from quasars, which are known to account for about 30% of the background.