Explanation: The image shows a group of island universes whose light reaches us after a journey of 500 million light years. Also known as Abell 2151, this cluster located in the boreal constellation of Hercules  is rich galaxies morphologically very different, some in training, others still haunted by the interaction between them. A few rather poor elliptical galaxies of gas and dust now and then incapable of giving birth to new stars. The colors in this composite image particularly deep, clearly show the star formation in galaxies with a blue tint whereas the older populations are visible with a gradation of colors closer to yellow. In fact, the storage of Hercules himself can be seen as the result of ongoing mergers in clusters of galaxies smaller. The image has been assessed, after a careful astrometric reduction, with the SDSS catalogs in blue, green PPMXL, PGC in heaven, USNO in red. From this examination is confirmed the considerable depth of the image as it is even exceeded magnitude 21 on diffuse objects. 

However, the most striking, clearly visible in an enlargement of the central regions of the cluster, is made by the discovery of the quasar QSO J1605 + 1745 showing a redshift or a shift towards the red spectral equal to z = 2.99. This means between us and this mysterious light source there is a quantifiable cosmic chasm between 7 and 10 billion light years !!! (http://en.wikipedia.org/wiki/Distance_measures_%28cosmology%29).

 The quasar is identified with the value of redshift or 2.99297 left immediately below with respect to NGC 6045.