"Hubble’s Advanced Camera for Surveys has observed a large portion of the Coma Cluster, stretching across several million light-years. The entire cluster is more than 20 million light-years in diameter, is nearly spherical in shape and contains thousands of galaxies.If I try to wrap my mind around the scale of this cluster, my head might explode.
Also known as Abell 1656, the Coma Cluster is over 300 million light-years away. The cluster, named after its parent constellation Coma Berenices, is near the Milky Way’s north pole. This places the Coma Cluster in an area that is not obscured by dust and gas from the plane of the Milky Way, and so is easily visible to observers here on Earth."
10-Jun-2008: The NASA/ESA Hubble Space Telescope captures the magnificent starry population of the Coma Cluster of Galaxies, one of the densest known galaxy collections in the Universe.To see the full image, click it and you will be taken to the appropriate page on spacetelescope.com where you can choose "image 1". The "publication JPEG" image isn't too large, but if you have a good broadband connection, try the "Large JPEG". It's a big one, so be patient.