From the ArcaMax Publishing, UK News Newsletter:
http://www.arcamax.com/news/uknews/s-574061-223209
LEICESTER, England (UPI) -- An international team of astronomers using
the European Space Agency's XMM-Newton X-ray observatory says it's
discovered a new kind of black hole.
The scientists, led by Sean Farrell of the University of Leicester,
England, said the newly found black hole weighs more than 500 solar
masses and is a missing link between lighter stellar-mass and heavier
super-massive black holes.
Stellar-mass black holes about 3 to 20 times as massive as the sun,
and super-massive black holes several million to several thousand
million times as massive as the sun, have long been known to exist.
Because of the large gap between the two extremes, scientists have
speculated the existence of a third, intermediate class of black
holes, with masses between a hundred thousand and several hundred
thousand solar masses.
Up until now, scientists were unable to confirm that this elusive
intermediate class actually existed. Farrell's team was analyzing data
obtained by XMM-Newton for neutron stars and white dwarves, when they
stumbled upon the black hole.
Called HLX-1, it is located approximately 290 million light years from
Earth.
The discovery will be detailed in the July 2 edition of the journal
Nature.