Information on some Nearby Superclusters Hydra Supercluster A nearby supercluster that is very similar in size and shape to the Virgo supercluster. The Hydra supercluster is also dominated by one rich cluster of galaxies - A1060, one of the nearest clusters in George Abell's catalog of rich galaxy clusters. Centaurus Supercluster The nearest large supercluster. The Centaurus supercluster is a long supercluster containing four rich galaxy clusters - A3526, A3565, A3574 and A3581 as well as hundreds of smaller groups of galaxies. A3526 is the dominant cluster among these and lies 140 million light years away. Seen from a large distance, the Virgo and Hydra superclusters might look like appendages to the Centaurus supercluster. The Centaurus supercluster lies near the Great Attractor - a large collection of matter affecting the motion of our galaxy and others. It is obscured by the plane of our own galaxy, but it is probable that the large cluster A3627 is largely responsible. Perseus-Pisces Supercluster A very prominant supercluster. This supercluster is a large sheet of galaxy groups scattered around three rich clusters - A262, A347 and A426. A426 is very rich cluster containing thousands of galaxies. Pavo-Indus Supercluster This is a fairly weak supercluster that marks one end of a long wall of galaxies that encompasses the Centaurus supercluster and probably the Virgo supercluster as well. The Pavo-Indus supercluster contains three rich galaxy clusters - A3656, A3698 and A3742. Coma Supercluster This is a small but very famous supercluster about 300 million light years away. There are two very rich galaxy clusters here - A1367 and A1656, both containing thousands of galaxies. A1656 is a very famous cluster, it is known as the Coma cluster, and as long ago as 1933 Fritz Zwicky studied the motion of the galaxies in this cluster to determine the amount of dark matter there is in the Universe. The Coma supercluster lies at the centre of The Great Wall, a vast filament of galaxies that stretches over hundreds of millions of light years, one end of which terminates on the Hercules supercluster. It was the first wall of galaxies recognised, but there are now many more known. Sculptor Supercluster Two superclusters in the Sculptor and Phoenix regions of the sky mark the position of a very long wall of thousands of galaxy groups stretching over nearly a billion light years of space. This is probably the longest of the nearby walls of galaxies. Hercules Supercluster Two famous and prominant superclusters lie here. The smaller and nearer one is probably the most famous being dominated by two rich clusters - A2197 and A2199 that lie very close to each other. This supercluster lies 400 million light years away. The second supercluster is only slightly further - 500 million light years, but it is a lot bigger and contains lots of rich galaxy clusters scattered around hundreds of smaller galaxy groups. Leo Supercluster Several large galaxy clusters on the border of Leo and Ursa Major at a distance of 450 million light years mark the presence of another large supercluster. The dominant clusters here are A1185 and A1228. Shapley Supercluster This is a very famous supercluster. Although it was only discovered in 1989 it is named after Harlow Shapley who first noticed an excess of galaxies in part of this region of the sky in the 1930's. The Shapley supercluster is a massive supercluster and many studies have been carried out on it and although it is not the biggest supercluster known, it is certainly one of the densest. There are two main concentrations - one at 500 million light years and a larger one at 650 million light years. There are at least twenty rich galaxy clusters among the thousands of galaxy groups in this supercluster, including three of the richest galaxy clusters known: A3558, A3559 and A3560. Pisces-Cetus Supercluster This is a region containing several major superclusters over 800 million light years away noted by Brent Tully in 1986. There are several very large superclusters here forming long wall structures hundreds of millions of light years in length. Bootes Supercluster There are a couple of prominant superclusters in Bootes over 800 million light years away but this region of the sky is more famous for the large Bootes Void that lies next to them. It is about 300 million light years across. There are no major clusters of galaxies in this void, but some individual galaxies have been noted, so it is not completely empty. Horologium Supercluster This is a huge supercluster 900 million light years away. It is not as dense as the Shapley supercluster but it contains a large number of rich galaxy clusters scattered across half a billion light years making it one of the largest known superclusters. This is another region of the sky in which Harlow Shapley noticed an excess of galaxies. Galaxy surveys in this part of the sky also show that there is a smaller supercluster lying in front of it 600 million light years away. In astronomy journals the Horologium supercluster is sometimes called the Horologium-Reticulum supercluster. Corona Borealis Supercluster The most distant of the famous superclusters. It has long been recognised that there are a large number of rich galaxy clusters in this small constellation. A2065 is probably the dominant cluster here, but there are another nine or ten large clusters here which are also rich. The supercluster is about 1 billion light years away. An all-sky plot of the 60000 brightest galaxies shows how galaxies clump together into large supercluster formations. The positions of some of the major superclusters are marked although only the nearest superclusters are prominant. Only four of these galaxies are visible with the naked eye. The large, dark, circular band is the plane of our own Galaxy where it is difficult to see distant galaxies because of all the foreground gas, dust and stars.