It is possible that Abell 2147 is actually part of the Hercules Cluster considering that it shares the same redshift of 550 million light years.

[4] The extraction regions were chosen based on an exposure corrected, combined GIS-2 and GIS-3 sky image.

Reference sky coordinates from the literature were used as input to a centroid routine to determine the cluster center right ascension and declination.

The extraction region was chosen to be the radius at which the radial profile reached 5*sigma times the background level.

SIS extaction radii were set at 0.70 times the GIS extraction radius.