The Hyperion proto-supercluster is the largest and earliest known proto-

supercluster A supercluster is a large group of smaller galaxy clusters or galaxy groups; they are among the largest known structures in the universe. The Milky Way is part of the Local Group galaxy group (which contains more than 54 galaxies), which in turn ...

, 5,000 times the mass of the

Milky Way The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked ey ...

and seen at 20% of the current age of the universe. It was discovered in 2018 by analysing the

redshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ...

s of 10,000 objects observed with the

Very Large Telescope The Very Large Telescope (VLT) is a telescope facility operated by the European Southern Observatory on Cerro Paranal in the Atacama Desert of northern Chile. It consists of four individual telescopes, each with a primary mirror 8.2 m across, ...

in Chile.

Discovery

The discovery was announced in late 2018. The discovery team led by Olga Cucciati used

computational astrophysics Computational astrophysics refers to the methods and computing tools developed and used in astrophysics research. Like computational chemistry or computational physics, it is both a specific branch of theoretical astrophysics and an interdiscipl ...

methods and

astroinformatics Astroinformatics is an interdisciplinary field of study involving the combination of astronomy, data science, machine learning, informatics, and information/communications technologies.dataset A data set (or dataset) is a collection of data. In the case of tabular data, a data set corresponds to one or more database tables, where every column of a table represents a particular variable, and each row corresponds to a given record of the d ...

s of galaxy

s, using a two-dimensional

Voronoi tessellation Voronoi or Voronoy is a Slavic masculine surname; its feminine counterpart is Voronaya. It may refer to *Georgy Voronoy (1868–1908), Russian and Ukrainian mathematician **Voronoi diagram ** Weighted Voronoi diagram ** Voronoi deformation density * ...

to correlate gravitational interaction ( virialization) of visible structures. The existence of non-visible (

dark matter Dark matter is a hypothetical form of matter thought to account for approximately 85% of the matter in the universe. Dark matter is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not ab ...

) structures was inferred. Correlation was based on redshift data captured in a

sky survey An astronomical survey is a general map or image of a region of the sky (or of the whole sky) that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of images, spectra, or other observations of ob ...

called

VIMOS-VLT Deep Survey The VIMOS-VLT Deep Survey (VVDS) is a redshift survey carried out by a collaboration between French and Italian astronomical institutes using the VIMOS spectrograph, mounted on the telescope Melipal (UT3) of the Very Large Telescope, located at ...

, using the

Visible Multi Object Spectrograph The Visible Multi-Object Spectrograph (VIMOS) is a wide field imager and a multi-object spectrograph installed at the European Southern Observatory's Very Large Telescope (VLT), in Chile. The instrument used for deep astronomical surveys deliver ...

(VIMOS) instrument of the

in Chile, and other surveys to a lesser extent. Spectroscopic redshift data for 3,822 objects (galaxies) was selected. The discovery was published in ''

Astronomy & Astrophysics ''Astronomy & Astrophysics'' is a monthly peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics. The journal is run by a Board of Directors representing 27 sponsoring countries plus a re ...

'' in September 2018.

Physical description

The structure is estimated to weigh 4.8 × 10¹⁵

solar mass The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass o ...

es (about 5,000 times the mass of the

) and to extend . It lies within the two

square degree __NOTOC__ A square degree (deg2) is a non- SI unit measure of solid angle. Other denotations include ''sq. deg.'' and (°)2. Just as degrees are used to measure parts of a circle, square degrees are used to measure parts of a sphere. Analogous to ...

Cosmic Evolution Survey The Cosmic Evolution Survey (COSMOS) is a Hubble Space Telescope (HST) Treasury Project to survey a two square degree equatorial field with the Advanced Camera for Surveys (ACS). The largest survey ever undertaken by HST, the project incorpora ...

(COSMOS) field of the constellation

Sextans Sextans is a minor equatorial constellation which was introduced in 1687 by Johannes Hevelius. Its name is Latin for the astronomical sextant, an instrument that Hevelius made frequent use of in his observations. Notable features Sextans as ...

. Hyperion's redshift is z=2.45 putting it 11 billion light years from Earth; it existed at less than 20% of the present age of the Universe. Eventually it is "expected to evolve into something similar to the immense structures in the local universe such as the superclusters making up the

Sloan Great Wall The Sloan Great Wall (SGW) is a cosmic structure formed by a giant wall of galaxies (a galaxy filament). Its discovery was announced from Princeton University on October 20, 2003, by J. Richard Gott III, Mario Jurić, and their colleagues, base ...

or the

Virgo Supercluster The Virgo Supercluster (Virgo SC) or the Local Supercluster (LSC or LS) is a mass concentration of galaxies containing the Virgo Cluster and Local Group, which itself contains the Milky Way and Andromeda galaxies, as well as others. At leas ...

Use in cosmology

The supercluster contains dark matter, evidenced by a mismatch between the visible objects in it and their computed gravitational binding. As a relic from the early Universe, the dark matter data could be used to test cosmological theories. As the 2018 paper authors note, "the identification of massive/complex proto-clusters at high redshift could be useful to give constraints on dark matter simulations" of the

Lambda-CDM model The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parameterization of the Big Bang cosmological model in which the universe contains three major components: first, a cosmological constant denoted by Lambda (Greek Λ) associated with ...

Discovery

Physical description

Use in cosmology

See also

References

Sources

Further reading