This new image from NASA gives us a landscape (spacescape?) of a galaxy cluster known as Abell 520, some 2.4 billion light years away from Earth. Abell 520 is of interest to scientists because, in the aftermath of massive collisions of galaxy clusters, its dark matter contains fewer galaxies than scientists would predict if, as thought, galaxies and dark matter stay together even during collisions. Superimposed on the true-color image of the galaxy cluster are false-color shadings that scientists have added to illustrate hot gas (green), starlight from within the galaxies (orange), and dark matter (blue). The illustration combines data from NASA's Chandra X-ray Observatory and the Canada-France-Hawaii Telescope.
Below, recent Pictures of the Day:
We want to hear what you think about this article. Submit a letter to the editor or write to email@example.com.