Ashes from massacred planets hide black holes

PLANETS and asteroids may be smashing into each other by the thousand around monster black holes. Dust from the collisions could explain why many of these colossal objects, which would otherwise shine brightly as they swallow nearby matter, are hidden from view.

Most galaxies like the Milky Way harbour a central black hole with a mass upwards of a million suns. While the Milky Way’s black hole is currently inactive, many in other galaxies are swallowing up gas from dense discs that surround them, producing copious X-rays and other radiation in the process.

In addition to providing fodder for the black holes, these discs may give birth to millions of stars, explaining the dense star clusters seen in some galaxies’ hearts.

Full Story: http://www.newscientist.com/article/mg21128304.100-ashes-from-massacred-planets-hide-black-holes.html