A rapidly rotating super massive black hole has been found in
the heart of a spiral galaxy by ESA’s XMM-Newton and NASA’s
NuSTAR space observatories, opening a new window into how
galaxies grow. Super massive black holes are thought to lurk in
the center of almost all large galaxies, and scientists believe
that the evolution of a galaxy is inextricably linked with the
evolution of its black hole. How fast a black hole spins is
thought to reflect the history of its formation. In this
picture, a black hole that grows steadily, fed by a uniform flow
of matter spiraling in, should end up spinning rapidly. Rapid
rotation could also be the result of two smaller black holes
merging. On the other hand, a black hole buffeted by small
clumps of material hitting from all directions will end up
rotating relatively slowly. These scenarios mirror the formation
of the galaxy itself, since a fraction of all the matter drawn
into the galaxy finds its way into the black hole. Because of
this, astronomers are keen to measure th