
Chandra’s image of this distant galaxy revealed a surprising number of point-like sources that have been identified as black holes and neutron stars in binary star systems. Since black holes and neutron stars are the end state of the brightest and most massive stars, this detection shows that NGC 1553 once contained many very bright, massive stars, in marked contrast to the present population of low-mass faint stars that now dominate the galaxy. The bright central X-ray source is probably due to a supermassive black hole in the nucleus of the galaxy.
