(globular cluster in which a black hole has been identified)
NGC 3201 (aka Caldwell 79) is a
globular cluster with a radius of 40 ly and a
presumed age of more than 10 gigayears (one determination
is 10.24 Gy).
It is of interest because a probable stellar black hole
has been identified, using the radial velocity of a star
that indicates it is orbiting something invisible and very massive.
It is assumed that globular clusters generally host multiple stellar
mass black holes, simply based upon the large number of resident stars,
but currently they can only be identified when specific clues are
available, such as in this case.
(globular cluster,RV method)
| || |