Abell 901
Abell 901 is a massive galaxy cluster in the constellation Leo . It is about 2.6 billion light years from Earth and about 16 million light years in extent. Together with Abell 902, it forms a supercluster . The name is derived from the entry in the Abell catalog .
Both became known through the discovery of strong X-rays by the ROSAT satellite in the 1990s, which emanates from the galaxy clusters. The distribution of dark matter in the area of the galaxy clusters could be reconstructed from images of the Hubble Space Telescope , XMM-Newton and other images of the region .