Astronomy
-
AstronomyX-ray Data Reveal Black Holes Galore
Using a sensitive, new X-ray telescope, astronomers have identified the origin of the high-energy part of the X-ray background and found that supermassive black holes at the cores of galaxies are far more numerous than visible-light surveys indicate.
By Ron Cowen -
AstronomyA Dark View of the Universe
Two new studies suggest that galaxies may be surrounded by vast halos of dark matter extending at least 1.5 million light-years from each galaxy's center.
By Ron Cowen -
-