The Telescopium−Grus Cloud is a

galaxy filament In cosmology, galaxy filaments are the largest known structures in the universe, consisting of walls of galactic superclusters. These massive, thread-like formations can commonly reach 50 to 80 megaparsecs ()—with the largest found to date b ...

in the constellations of Pavo,

Indus The Indus ( ) is a transboundary river of Asia and a trans- Himalayan river of South and Central Asia. The river rises in mountain springs northeast of Mount Kailash in the Western Tibet region of China, flows northwest through the dis ...

, and

Telescopium Telescopium is a minor constellation in the southern Celestial sphere, celestial hemisphere, one of twelve named in the 18th century by French astronomer Nicolas-Louis de Lacaille and one of several depicting scientific instruments. Its name i ...

. It was first defined by astronomer

Brent Tully Richard Brent Tully (born March 9, 1943) is a Canadian-born American astronomer at the Institute for Astronomy in Honolulu, Hawaii. Born in Toronto, Ontario, and raised in Vancouver, British Columbia, Tully's specialty is the astrophysics of ga ...

in his book ''The Nearby Galaxies Atlas'' and its companion book ''The Nearby Galaxies Catalog.'' In 2014, it was announced that the

Southern Supercluster Strand The Southern Supercluster Strand is a galaxy filament that incompasses the Southern Supercluster and the Telescopium−Grus Cloud. In 2014, it was announced that the Southern Supercluster Strand is a lobe in a greater supercluster, Laniakea Sup ...

is a lobe in a greater supercluster, Laniakea, that is centered on the

Great Attractor The Great Attractor is a region of gravitational attraction in intergalactic space and the apparent central gravitational point of the Laniakea Supercluster of galaxies that includes the Milky Way galaxy, as well as about 100,000 other galaxi ...

. This would mean that the

's components, the Telescopium−Grus Cloud and the

Southern Supercluster The Southern Supercluster is a nearby supercluster located around in the constellations of Cetus, Fornax, Eridanus (constellation), Eridanus, Horologium (constellation), Horologium, and Dorado. It was first identified in 1953 by Gérard de Vaucou ...

would be part of this new supercluster. The

Virgo Supercluster The Local Supercluster (LSC or LS), or Virgo Supercluster is a formerly defined supercluster containing the Virgo Cluster and Local Group, which itself contains the Milky Way and Andromeda galaxies, as well as others. At least 100 galaxy group ...

would also be part of this greater supercluster, thus becoming the local supercluster.

Physical characteristics

The Telescopium−Grus Cloud is a collection of at least 24

galaxy groups A galaxy group or group of galaxies (GrG) is an aggregation of galaxies comprising about 50 or fewer gravitationally bound members, each at least as luminous as the Milky Way (about 1010 times the luminosity of the Sun); collections of galaxies ...

. It is low density

, with no central concentration of galaxies. The filament along with the Pavo-Indus Supercluster form parts of a wall bounding the

Local Void The Local Void is a vast, Void (astronomy), empty region of Interstellar medium, space, lying adjacent to the Local Group. Discovered by R. Brent Tully, Brent Tully and J. Richard Fisher, Rick Fisher in 1987, the Local Void is now known to be c ...

. Likewise, both structures also form a wall bounding the

Sculptor Void Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable ...

. The Telescopium−Grus Cloud is a branch of a larger filament extending from the

Centaurus Cluster 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 clust ...

that is known as the Southern Supercluster Strand which also encompasses the

Fornax Fornax () is a constellation in the southern celestial hemisphere, partly ringed by the celestial river Eridanus (constellation), Eridanus. Its name is Latin for furnace. It was named by French astronomer Nicolas Louis de Lacaille in 1756. Forna ...

- Eridanus-

Dorado Dorado (, ) is a constellation in the Southern Sky. It was named in the late 16th century and is now one of the 88 modern constellations. Its name refers to the mahi-mahi (''Coryphaena hippurus''), which is known as ''dorado'' ("golden") in Sp ...

complex which is also known as the

. The Southern Supercluster Srand extends all the way to the

Perseus–Pisces Supercluster The Perseus–Pisces Supercluster (SCl 40) is one of the largest known structures in the universe. Even at a distance of 250 million light-years, this chain of galaxy clusters extends more than 40° across the northern winter sky. The Perseus– ...

. The Telescopium−Grus Cloud which is part of the Southern Supercluster Strand, along with the Centaurus–Puppis–PP filament, which contains the

Antila Wall Antila is a Finnish surname. Notable people with the surname include: * John Antila (1902-1969), American businessman and politician * Juho Erkki Antila (1856–1920), Finnish politician * Kirsi Antila (née The birth name is the name o ...

and both extend to the

, form a wall bounding the

Observational history

Even before the Telescopium−Grus Cloud was identified, major concentrations in the filament were identified: group G27 which would later be known as the Grus Group, group G39 which would later be known as the NGC 134 Group, group G45 (Pavo-Indus) which would later be known as the NGC 7079, NGC 7144, NGC 7196 and NGC 7213 groups, and group G52 which would later be known as the Telescopium Cluster. These concentrations were first identified by astronomer

Gérard de Vaucouleurs Gérard Henri de Vaucouleurs (25 April 1918 – 7 October 1995) was a French astronomer best known for his studies of galaxies. Life and career Gérard de Vaucouleurs was born on April 25, 1918 in Paris, he took the maiden name of his mother ...

in 1975. In 1987, astronomer

with colleague Richard Fisher first identified and described the Telescopium−Grus Cloud in his book ''The Nearby Galaxies Atlas'' and its companion book ''The Nearby Galaxies Catalog.'' Later in 1992, Fouque et al. grouped the Telescopium−Grus Cloud, also known as cloud 61 in the book ''The Nearby Galaxies Atlas'' along with the Pavo-Indus Spur (cloud 62), the Pisces Austrinus Spur (cloud 63), the Pegasus Cloud and Pegasus Spur (clouds 64 and 65) with the Pavo-Indus Supercluster which at the time was known as the Indus Supercluster. However in a paper published in 1993 titled, ''Dynamics of the Pavo-Indus and Grus clouds of galaxies.,'' Fouque et al. instead classified the Telescopium−Grus Cloud as a connection between the

Pavo–Indus Supercluster The Pavo–Indus Supercluster is a neighboring supercluster located about away in the constellations of Pavo, Indus, and Telescopium. The supercluster contains three main clusters, Abell 3656, Abell 3698, and Abell 3742. Other groups and clu ...

and the Local Supercluster. In 2001, Pebeles et.al identified another

that originates at the

Virgo Cluster The Virgo Cluster is a cluster of galaxies whose center is 53.8 ± 0.3 Mly (16.5 ± 0.1 Mpc) away in the Virgo constellation. Comprising approximately 1,300 (and possibly up to 2,000) member galaxies, the cluster forms the heart of the larger ...

, passes through a knot of galaxies containing the

Sombrero Galaxy The Sombrero Galaxy (also known as Messier Object 104, M104 or NGC 4594) is a peculiar galaxy of unclear classification in the constellation borders of Virgo and Corvus, being about from the Milky Way galaxy. It is a member of the Virgo II Gr ...

, then passes at its closest point to the

Milky Way The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...

at the Centaurus/M83 group, and then passes from the perspective from the Milky Way though the

galactic plane The galactic plane is the plane (geometry), plane on which the majority of a disk-shaped galaxy's mass lies. The directions perpendicular to the galactic plane point to the galactic poles. In actual usage, the terms ''galactic plane'' and ''galac ...

near the Circinus galaxy to meet up with the Telescopium−Grus Cloud. In 2013, Courtois et al. identified a filament extending from the

that is associated with a structure intentfied in 1956 by

: The

. The Southern Supercluster contains 3 major concentrations of galaxies: The

Fornax Cluster The Fornax Cluster is a cluster of galaxies lying at a distance of 19 megaparsecs (62 million light-years). It has an estimated mass of solar masses, making it the second richest galaxy cluster within 100 million light-years, after the consider ...

, The Dorado Group and Eridanus cluster, along with many other groups of galaxies. The Telescopium−Grus Cloud would now be considered a branch of this larger filament along with the Southern Supercluster which is also known as the

– Eridanus–

complex. The Telescopium−Grus Cloud would be designated as branch SSCb of this filament, and the Southern Supercluster would be designated as branch SSCa. In 2017, Pomarède et al. revealed that this filament, now known as the Southern Supercluster strand along with another filament known as the Antila Strand, extend all the way to the

List of groups

Below is a list of groups in the Telescopium–Grus Cloud according to astronomer

. : Column 1: The name of the group in Tully's NBGG : Column 2: The right ascension for epoch 2000. : Column 3: The declination for epoch 2000. : Column 4: Number of members of the group. : Column 5: Brightest member of the group : Column 6: Redshift of the group. : Column 7: Distance of the group (Millions of light-years). : Column 8: Cross-Identifications with other catalogs. (Sources for data columns:)

References

{{DEFAULTSORT:Telescopium-Grus Cloud Galaxy filaments Large-scale structure of the cosmos Astronomical objects discovered in 1987 Southern Supercluster Strand

Physical characteristics

Observational history

List of groups

See also

References