"A Look to the Heavens"

“This image shows a majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies, which lies 320 million light-years away, in the northern constellation Coma Berenices. The galaxy, known as NGC 4911, contains rich lanes of dust and gas near its center. These are silhouetted against glowing newborn star clusters and iridescent pink clouds of hydrogen, the existence of which indicates ongoing star formation.

Click image for larger size.

Galaxy clusters are the largest gravitationally bound structures in the universe and are thought to have formed piecemeal over cosmic time. Throughout the known, Hubble length universe, hundreds of millions of galaxies have clumped together, forming these super clusters and a series of great walls of galaxies which are separated by vast voids of empty space. Several of these elongated super clusters have formed a series of walls, one after another, spaced from 500 million to 800 million light years apart, such that in one direction alone, 13 Great Walls have formed with the inner and outer walls separated by less than 7 billion light years. Some recent theories estimate that these galactic walls may have taken from 80 billion to 100 billion, to 150 billion years to form.

Millions of galaxies over one hundred million light years across, moving in the same direction, have penetrated the center of the local super cluster of galaxies located in the vicinity of the Centaurus and Hydra and constellations. The Coma cluster at the center of the CfA2 Great Wall is one of the largest observed structures in the Universe, containing over 10,000 galaxies and extending more than 1.37 billion light years in length.”

- Casey Kazan, http://www.dailygalaxy.com/