Our new paper is out in Nature this week (advanced online version), and the press releases are a’flying. We found what’s called an “ultraluminous X-ray source” (ULX) in a nearby galaxy, Andromeda (M31), and for the very first time actually caught its radio emission from the jets evolving over time! Until now there’s been a big debate about whether these ULXs are a long-sought-after class of black holes in an intermediate mass range between known stellar and supermassive black holes. It’s an important point, because there are a lot of theories about how black holes are created and evolve, and there are all sorts of reasons why intermediate mass black holes should exist, but so far no surefire case of one has been discovered. Because ULXs are so bright, a lot of people have speculated that they could be representative of the “missing” class of intermediate mass black holes. I would have liked that to be the case too, however our work here seems to support that these are mostly run-of-the-mill black holes just accreting near their physical limits. Anyway, here is a nice summary of the article if you’re interested:
http://arstechnica.com/science/2012/12/astronomers-locate-a-miniature-quasar-in-andromeda/
