Corona Borealis is a small constellation in the Northern Celestial Hemisphere. It is one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and remains one of the 88 modern constellations. Its brightest stars form a semicircular arc. Its Latin name, inspired by its shape, means "northern crown". In classical mythology Corona Borealis generally represented the crown given by the god Dionysus to the Cretan princess Ariadne and set by him in the heavens. Other cultures likened the pattern to a circle of elders, an eagle's nest, a bear's den, or even a smokehole. Ptolemy also listed a southern counterpart, Corona Australis, with a similar pattern.
A supercluster is a large group of smaller galaxy clusters or galaxy groups; it is among the largest known structures of the universe. The Milky Way is part of the Local Group galaxy group, which in turn is part of the Virgo Supercluster, which is part of the Laniakea Supercluster. The large size and low density of superclusters means that they, unlike clusters, expand with the Hubble expansion. The number of superclusters in the observable universe is estimated to be 10 million.
The Virgo Supercluster or the Local Supercluster is a mass concentration of galaxies containing the Virgo Cluster and Local Group, which in turn contains the Milky Way and Andromeda galaxies. At least 100 galaxy groups and clusters are located within its diameter of 33 megaparsecs. The Virgo SC is one of about 10 million superclusters in the observable universe and is in the Pisces–Cetus Supercluster Complex, a galaxy filament.
The Great Attractor is a gravitational anomaly in intergalactic space and the apparent central gravitational point of the Laniakea Supercluster. The observed anomalies suggest a localized concentration of mass millions of times more massive than the Milky Way. However, it is inconveniently obscured by our own Milky Way's galactic plane, lying behind the Zone of Avoidance (ZOA), so that, in visible light wavelengths, the Great Attractor is difficult to observe directly.
The Centaurus Cluster (A3526) is a cluster of hundreds of galaxies, located approximately 170 million light years away in the Centaurus constellation. The brightest member galaxy is the elliptical galaxy NGC 4696 (~11m). The Centaurus cluster shares its supercluster, the Hydra-Centaurus Supercluster, with IC4329 Cluster and Hydra Cluster.
The Hydra-Centaurus Supercluster, or the Hydra and Centaurus Superclusters, is a supercluster in two parts, the closest neighbour of Virgo Supercluster.
Abell 2029 or A2029 is a large cluster of galaxies 315 megaparsecs away in the constellation Virgo. A2029 is a Bautz–Morgan classification type I cluster due to its large central galaxy, IC 1101. Abell 2029 has a diameter of 5.8–8 million light-years. This type of galaxy is called a cD-type brightest cluster galaxy and may have grown to its large size by accreting nearby galaxies. Despite its relaxed state, it is the central member of a large supercluster which shows clear signs of interaction.
The Pavo-Indus Supercluster is a neighboring supercluster located about 60–70 Mpc (196–228 Mly) away in the constellations of Pavo, Indus, and Telescopium. The supercluster contains three main clusters, Abell 3656, Abell 3698, and Abell 3742.
The Antlia Cluster is a cluster of galaxies located in the Hydra-Centaurus Supercluster. The Antlia Cluster is the third-nearest to the Local Group after the Virgo Cluster and Fornax Cluster. Antlia's distance from Earth is 40.5 megaparsecs to 40.9 Mpc (133.4 Mly) and can be viewed from Earth in the constellation Antlia. The Antlia Cluster should not be confused with the Antlia Dwarf galaxy.
In physical cosmology, galaxy filaments are the largest known structures in the universe. They are massive, thread-like formations, with a typical length of 50 to 80 megaparsecs h−1 that form the boundaries between large voids in the universe. Filaments consist of gravitationally bound galaxies. Parts wherein many galaxies are very close to one another are called superclusters.
The Pisces–Cetus Supercluster Complex is a galaxy filament. It includes the Virgo Supercluster which in turn contains the Local Group, the galaxy cluster that includes the Milky Way. This filament is adjacent to the Perseus–Pegasus Filament.
The Hercules Superclusters refers to a set of two nearby superclusters of galaxies.
The Laniakea Supercluster, is the galaxy supercluster that is home to the Milky Way and approximately 100,000 other nearby galaxies. It was defined in September 2014, when a group of astronomers including R. Brent Tully of the University of Hawaii, Hélène Courtois of the University of Lyon, Yehuda Hoffman of the Hebrew University of Jerusalem, and Daniel Pomarède of CEA Université Paris-Saclay published a new way of defining superclusters according to the relative velocities of galaxies. The new definition of the local supercluster subsumes the prior defined local supercluster, the Virgo Supercluster, as an appendage.
The Corona Borealis Supercluster is a supercluster located in the constellation Corona Borealis and the most prominent example of its kind in the Northern Celestial Hemisphere. Dense and compact compared with other superclusters, its mass has been calculated to lie somewhere between 0.6 and 12 × 1016 solar masses (M⊙). It contains the galaxy clusters Abell 2056, Abell 2061, Abell 2065 (the most massive galaxy cluster within the supercluster), Abell 2067, Abell 2079, Abell 2089, and Abell 2092. Of these, Abell 2056, 2061, 2065, 2067 and A2089 are gravitationally bound and in the process of collapsing to form a massive cluster. This entity has an estimated mass of around 1 × 1016 M⊙. If there is inter-cluster mass present, then Abell 2092 may also be involved. It has been estimated to be 100 megaparsecs (330 million light-years) wide and 40 megaparsecs (130 million light years) deep. It has a redshift of 0.07, which is equivalent to a distance of around 265.5 megaparsecs (964 million light-years).
Abell 2061 is a galaxy cluster in the constellation of Corona Borealis. On a larger scale still, Abell 2061, along with Abell 2065, Abell 2067, Abell 2079, Abell 2089, and Abell 2092, make up the Corona Borealis Supercluster. It has a northeast southwest orientation and Abell 2067 lies 1.8 megaparsecs north of it.
The Microscopium Supercluster is a supercluster located in the constellation Microscopium. First noticed in the early 1990s, it has received little study. It is composed of Abell clusters 3695 and 3696, while the relations of Abell clusters 3693 and 3705 in the same field are unclear.
Abell 2067 is a galaxy cluster in the constellation of Corona Borealis. On a larger scale, Abell 2067, along with Abell 2061, Abell 2065, Abell 2079, Abell 2089, and Abell 2092, make up the Corona Borealis Supercluster. Abell 2061 lies 1.8 megaparsecs south of it and the two are likely interacting.
Abell 2162 is a galaxy cluster in the Abell catalogue located in the constellation Corona Borealis. It is a member of the Hercules Superclusters, the redshifts of the member galaxies of which lie between 0.0304 and 0.0414. The cluster hosts a massive Type-cD galaxy called NGC 6086.
Perseus–Pegasus Filament is a galaxy filament containing the Perseus-Pisces Supercluster and stretching for roughly a billion light years. Currently, it is considered to be one of the largest known structures in the universe. This filament is adjacent to the Pisces–Cetus Supercluster Complex.
