The BOSS Great Wall is a supercluster complex that was identified, using the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey (SDSS), in early 2016. It was discovered by a research team from several institutions, consisting of: Hiedi Lietzen, Elmo Tempel, Lauri Juhan Liivamägi, Antonio Montero-Dorta, Maret Einasto, Alina Streblyanska, Claudia Maraston, Jose Alberto Rubiño-Martín and Enn Saar. The BOSS Great Wall is one of the largest superstructures in the

observable universe The observable universe is a ball-shaped region of the universe comprising all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time, because the electromagnetic radiation from these obj ...

, though there are even larger structures known. The large complex has a mean

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 ...

of z ~ 0.47 (z times Hubble length ≈ 6.8 billion light years). It consists of two elongated superclusters, two large superclusters, and several smaller superclusters as well. The elongated superclusters form galaxy walls, with the larger of the two having a diameter of 186/h Mpc (supercluster A in the figure); the second wall's being 173/h Mpc (supercluster B). The other two main superclusters are moderately large, having diameters of 91/h Mpc and 64/h Mpc (superclusters D and C, respectively). The superstructure is roughly 1 billion light years in diameter, and has a total mass approximately 10,000 times 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 ...

galaxy. It contains at least 830 visible galaxies (represented in the figure within their respective superclusters), as well as many others that are not visible ( dark galaxies). The researchers used Minkowski functionals to verify the structure's overall shape and size; the first three quantifying the thickness, width, and length followed by the fourth determining the structure's overall curvature. The research team compared the luminosities and stellar masses within the superstructure to known high stellar mass galaxies within the SDSS's 7th data release, DR7. This allowed the team to scale the data using known values, from local superclusters, to determine the overall morphology of the BOSS Great Wall. It is currently debated amongst astronomers if the BOSS Great Wall may be considered a structure, due to the intricacies of its shape and overall size. The question of whether the supercluster complex is moving together or being slowly separated by the expanding universe is a key factor to this discussion. Nevertheless, when compared to several other chain structures, such as 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 ...

, the BOSS Great Wall's superclusters are far richer, containing more dense, high stellar mass galaxies. The BOSS Great Wall's discovery, and the data gained therein, should prove very beneficial for astronomers who study the overall structure of the

cosmic web The observable universe is a ball-shaped region of the universe comprising all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time, because the electromagnetic radiation from these obj ...

References

{{2016 in space Galaxy filaments Large-scale structure of the cosmos 20160226 Discoveries by SDSS