Why does this galaxy have so many big black holes? No one is
sure. What is sure is that NGC 922 is a ring galaxy created by
the collision of a large and small galaxy about 300 million
years ago. Like a rock thrown into a pond, the ancient collision
sent ripples of high density gas out from the impact point near
the center that partly condensed into stars. Pictured above is
NGC 922 with its beautifully complex ring along the left side,
as imaged recently by the Hubble Space Telescope. Observations
of NGC 922 with the Chandra X-ray Observatory, however, show
several glowing X-ray knots that are likely large black holes.
The high number of massive black holes was somewhat surprising
as the gas composition in NGC 922 -- rich in heavy elements --
should have discouraged almost anything so massive from forming.
Research is sure to continue. spans about 75,000 light years,
lies about 150 million light years away, and can be seen with a
small telescope toward the constellation of the furnace
(Fornax). Acknowledgement