Archive | September 20, 2014
Image

A monster black hole lurking inside one of the tiniest galaxies ever known

The black hole is five times the mass of the one at the center of our Milky Way galaxy. It is inside one of the densest galaxies known to date — the M60-UCD1 dwarf galaxy that crams 140 million stars within a diameter of about 300 light-years, which is only 1/500th of our galaxy’s diameter.

If you lived inside this dwarf galaxy, the night sky would dazzle with at least 1 million stars visible to the naked eye. Our nighttime sky as seen from Earth’s surface shows 4,000 stars.

The finding implies there are many other compact galaxies in the universe that contain supermassive black holes. The observation also suggests dwarf galaxies may actually be the stripped remnants of larger galaxies that were torn apart during collisions with other galaxies rather than small islands of stars born in isolation.

“We don’t know of any other way you could make a black hole so big in an object this small,” said University of Utah astronomer Anil Seth, lead author of an international study of the dwarf galaxy published in Thursday’s issue of the journal Nature.

via: http://www.nasa.gov/press/2014/september/hubble-helps-find-smallest-known-galaxy-containing-a-supermassive-black-hole/