Perseus Galaxy Cluster (Abell 426) and Central Galaxy NGC 1275
The Perseus Galaxy Cluster (Abell 426) is one of the nearest galaxy clusters containing 190 members which are gravitationaly bound to the massive central galaxy NGC 1275. The cluster's angular size is several degrees, lying at a distance around 240 million light years, and receding from us at 5,220 km/s due to the expansion of space. Although inconspicuous in visible light, it is one of the brightest objects in the night sky in the X-ray band due to accretion around numerous central galactic supermassive black holes and interactions between strong magnetic fields with an envelope of hot, ionized plasma heated to millions of K.
See Chandra's X-ray image here
On larger scales, the Perseus Cluster is part of the Perseus-Pisces Galaxy Supercluster which is one of the largest and most massive objects in the Universe. It contains over a thousand gravitationally bound galaxies subtending over 40 degrees on the night sky.
The supercluster is, in turn, a part of the Perseus-Pegasus Filament of galaxies which extends over a billion light years.
NGC 1275 is the brightest and most massive galaxy in the Perseus Cluster, and situated near the cluster's center of gravity. It is a giant elliptical galaxy approximately 181,000 light years in diameter, with a stellar mass of 243 billion solar, about 4 times greater than the Milky Way's (~61 billion solar). The galaxy is a complex structure whose properties are determined by 1) a central supermassive black hole with an accretion disk of around 800 million solar masses, 2) a small foreground spiral galaxy approaching the main galaxy at 3,000 km/sec, and merging with it in a moderate burst of new star formation, 3) long, thin filaments of relatively cool hydrogen gas held intact by strong magnetic lines, and 4) infall of thousands of stars and globular clusters which "condense" from the surrounding intergalactic medium, and descend like snow upon the periphery of the main galaxy. NGC 1275 is a strong source of radio waves (radio source Perseus A) generated by synchrotron emission from the magnetic fields around the central black hole's accretion disk and polar jets. It also manifests a quasar-like active galactic nucleus of the Seyfert 1.5 type characterized by emission lines of highly ionized gas and strong X-ray emissions.
My modest contribution reveals no hint of the turmoil within this chaotic object revealed by these HST images.