November 29, 2013
A bright black hole in the Pinwheel galaxy has been shining us on, astronomers say – this intergalactic trickster puts out light like a big black hole but it’s really quite tiny. M 101 ULX-1, described in the journal Nature, may force scientists to keep hunting for more “intermediate” black holes – and rethink their understanding of them.
Black holes are thought to be remains of dead stars whose entire mass has collapsed to a tiny point. They warp space-time so badly that not even light can escape. The small ones created by single stars can be up to roughly 30 times the mass of our sun. The supermassive ones at the centers of galaxies can be billions of solar masses.
But astronomers also think there’s a class of black hole that falls in between those mass-sucking monsters that are too big to be made from a single star, and too small to be the enormous eye of a spiral galaxy.