Hubble finds dark matter ring in galaxy cluster
Date: 15 May 2007
Satellite: Hubble Space Telescope
Depicts: Cl 0024+17 (ZwCl0024+1652)
Copyright: NASA, ESA, M.J. Jee and H. Ford (Johns Hopkins University)
An international team of astronomers using the NASA/ESA Hubble Space Telescope has discovered a ring of dark matter that was formed long ago during a titanic collision between two massive galaxy clusters. It is the first time that a dark matter distribution has been found that differs substantially from the distribution of ordinary matter.
This image shows the galaxy cluster Cl 0024+17 (ZwCl 0024+1652) as seen by Hubble's Advanced Camera for Surveys. North is to the right, east is up.
The image displays faint faraway background galaxies that had their light bent by the cluster's strong gravitational field. By mapping the distorted light and using it to deduce how dark matter is distributed in the cluster, astronomers spotted the ring of dark matter. One of the background galaxies is located about two times further away than the yellow cluster galaxies in the foreground, and has been multiple-imaged into five separate arc-shaped components, seen in blue.
