Astronomers using the Hubble Space Telescope say they have made a significant advance toward confirming the existence of black holes -- massively heavy, super-condensed galactic centers that are so strong that even light cannot travel fast enough to escape their pull.
The Hubble findings, announced in Washington yesterday, also show that black holes may be more common than was formerly believed.
A black hole, by its very nature, cannot be seen. But the Hubble images show that stars in a nearby galaxy, M32, become extremely concentrated toward the center. Some strong -- and invisible -- force is apparently exerting enough gravity to suck the stars toward the black hole.
The astronomers have calculated that the apparent black hole weighs about 3 million times more than the sun, though it occupies about the same space.