Giant Arc
| Object type | Large-scale structure of the Universe, galaxy filament  |
|---|---|
| Constellation | Boötes |
| required | |
| Declination | required |
| Redshift | 0.8 |
| Distance | 9,300,000,000, 9,200,000,000 ly (5.9×1014, 5.8×1014 AU) |
The Giant Arc is a large-scale structure discovered in June 2021 that spans 3.3 billion light years.[1][2] This structure of galaxies exceeds the 1.2 billion light year threshold of the currently accepted model of cosmology, potentially challenging the cosmological principle that at large enough scales the universe is considered to be the same in every place (homogeneous) and in every direction (isotropic).[2] The Giant Arc consists of galaxies and galactic clusters, as well as gas and dust. It is located 9.2 billion light-years away at redshift ~0.8, and it stretches across roughly 1/15th of the radius of the observable universe.[3][2] It was discovered using data from the Sloan Digital Sky Survey by the team of Alexia M. Lopez, a doctoral candidate in cosmology at the University of Central Lancashire.[1][4][5]
The Giant Arc was discovered using a new method for finding large-scale structure by looking for intervening Mg II absorption lines in background quasars.[2]
It and the Big Ring may be part of the same large-scale structure, with a galaxy filament potentially connecting the two structures.[6][7]
In February 2025, a team led by Dr. Till Sawala from the University of Helsinki argued that the existence of the Giant Arc does not contradict the cosmological principle, because similarly-sized structures were predicted in their cosmological simulations.[8] Lopez and her team refuted this claim in April 2025, demonstrating that enhanced simulations do not predict Giant Arc-sized structures.[9]
If the Giant Arc were visible in the night sky it would form an arc occupying as much space as 20 full moons, or 10 degrees on the sky.[10]
See also
[edit]- Huge-LQG
- Sloan Great Wall
- CfA2 Great Wall
- South Pole Wall
- BOSS Great Wall
- Hercules–Corona Borealis Great Wall
References
[edit]- ^ a b Hond, Bas den (8 June 2021). "Line of galaxies is so big it breaks our understanding of the universe". New Scientist.
- ^ a b c d Lopez, Alexia M; Clowes, Roger G; Williger, Gerard M (21 October 2022). "A Giant Arc on the Sky". Monthly Notices of the Royal Astronomical Society. 516 (2): 1557–1572. arXiv:2201.06875. doi:10.1093/mnras/stac2204.
- ^ Mann, Adam (11 June 2021). "'Giant arc' stretching 3.3 billion light-years across the cosmos shouldn't exist". LiveScience.
- ^ Fox-Skelly, Jasmin (March 3, 2023). "The giant arcs that may dwarf everything in the cosmos". BBC. Retrieved 2023-09-17.
- ^ "Discovery of a Giant Arc in distant space adds to challenges to basic assumptions about the Universe". University of Central Lancashire. 7 June 2021. Retrieved 2024-02-06.
- ^ Devlin, Hannah (2024-01-11). "Newly discovered cosmic megastructure challenges theories of the universe". The Guardian. ISSN 0261-3077. Retrieved 2024-02-06.
- ^ Lopez, Alexia M.; Clowes, Roger; Williger, Gerard (2025-02-13). "Investigating ultra-large large-scale structures: potential implications for cosmology". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences. 383 (2290): 20240029. arXiv:2409.14894. Bibcode:2025RSPTA.38340029L. doi:10.1098/rsta.2024.0029. PMID 39938543.
- ^ Sawala, Till; Teeriaho, Meri; Frenk, Carlos S.; Helly, John; Jenkins, Adrian; Racz, Gabor; Schaller, Matthieu; Schaye, Joop (March 2025). "The Emperor's New Arc: gigaparsec patterns abound in a ΛCDM universe". Monthly Notices of the Royal Astronomical Society. arXiv:2502.03515. Bibcode:2025MNRAS.tmpL..21S. doi:10.1093/mnrasl/slaf021. ISSN 0035-8711.
- ^ M Lopez, A.; Clowes, R. G. (2025). "Gigaparsec structures are nowhere to be seen in ΛCDM: An enhanced analysis of LSS in FLAMINGO-10K simulations". arXiv:2504.14940 [astro-ph.CO].
- ^ New Astronomy: Large-Scale Structure in our Universe by: Alexia M. Lopez. Ness E Tainment. 2021-06-07. Retrieved 2024-09-14 – via YouTube.
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