According to this principle, a single huge structure is not supposed to appear in a specific area of the sky, so what if we are talking about two giant structures relatively close to each other?
Five years ago, researchers discovered what was known as the “Giant Sagittarius,” a huge crescent of galaxies extending 3.3 billion light-years across, and located about 9.2 billion light-years from Earth.
In 2024, the same team announced the discovery of a second, more surprising structure, dubbed the “big ring.” The diameter of this structure is 1.3 billion light-years, and it is located at an approximately similar distance, with only 12 degrees separating it from the “giant arc” in the sky.
The discoverer of the two structures, Alexia Lopez, a researcher from the University of Central Lancashire, said: “We might expect there to be one very massive structure in our entire observable universe. However, the Big Ring and the Giant Arc are two massive structures, and they are even cosmic neighbors, which is exceptionally interesting.”
She added: “Neither of these massive structures can be easily explained in light of our current understanding of the universe. Their extremely massive sizes, distinct shapes, and cosmic proximity certainly tell us something important, but what exactly?”
No definitive explanation has yet been provided for the existence of these two structures. According to the cosmological principle, galaxies are supposed to be evenly distributed on large scales, despite the presence of galactic clusters and what is known as the cosmic web.
Cosmologists estimate the theoretical limit of the size of cosmic structures at about 1.2 billion light-years. But the “giant arc” is about three times larger than this limit, while the circumference of the “large ring” is close to the length of the arc itself.
Lopez said that current theories did not expect the existence of structures of this size, noting that their cosmic proximity makes the issue even more striking.
Scientists will need more observations to confirm these results, and to understand whether these giant structures reveal a flaw in current cosmological models or require a new explanation.
The results of the research on the “Large Ring” were presented at the 243rd meeting of the American Astronomical Society, before they were later published in the journal Cosmology and Astroparticle Physics.
