Abell 2142 [SEP] constellation
Abell 2142
Abell 2142, or A2142, is a huge, X-ray luminous galaxy cluster in the constellation Corona Borealis. It is the result of a still ongoing merger between two galaxy clusters. The combined cluster is six million light years across, contains hundreds of galaxies and enough gas to make a thousand more. It is "one of the most massive objects in the universe."
X-Ray image.
The adjacent image was taken 20 August 1999 with the Chandra X-ray Observatory's 0.3
same visual field through a telescope. Abell 2142 is a huge (six million light-year diameter), X-ray luminous galaxy cluster that is the result of an ongoing merger between two galaxy clusters. It has a redshift of 0.0909 (meaning it is moving away from us at 27,250 km/s) and a visual magnitude of 16.0. It is about 1.2 billion light-years away. Another galaxy cluster in the constellation, RX J1532.9+3021, is approximately 3.9 billion light-years from Earth