This is a typical rich galaxy cluster, with up to 2000 members. Its large mass is also shown by the high peculiar velocities[?] of many of its galaxies, sometimes as high as 1,600 km/s (with respect to the cluster's center). For comparison, the cluster redshift equals to a velocity of only 1,100 km/s.
The giant M87 galaxy is believed to be the dominating member of this cluster.
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