There is also an article on the ABC about dark matter in ZwC10024+1652 .
Astronomers discover 'dark matter ring'
International astronomers say they have found the strongest evidence yet of the existence of the mysterious substance known as dark matter. Scientists believe invisible dark matter accounts for 90 per cent of the universe's mass and holds together galaxy clusters. Otherwise, galaxies would only have the gravity from their visible stars, which would not be enough to keep them from flying apart. A NASA team using the Hubble Space Telescope has now detected what it describes as a ghostly ring of dark matter around a cluster of galaxies 5 billion light years away...
http://www.abc.net.au/news/newsitems...5/s1924778.htm