Observations of the most ancient galaxies have helped astrophysicists discover another "space desert" - a sphere about 500 million light years across in the constellation Pisces, almost completely devoid of stars. Photos of this anomaly were published in the Astrophysical Journal.
“The presence of such a zone of emptiness in the young Universe dramatically changes our understanding of how it became transparent and how the first galaxies were born. If our observations are correct, then we can say that matter is distributed in the universe more heterogeneously than we thought before,”says Stephen Furlanetto from the University of California at Los Angeles (USA).
According to cosmologists, matter is distributed throughout the Universe not evenly, but in the form of a giant web - threadlike clusters of visible and dark matter interconnected with each other, separated by giant space deserts. These voids and clusters are the result of a kind of "echo" of the Big Bang, the so-called baryonic acoustic oscillations, which distribute matter unevenly throughout the rapidly expanding Universe.
The cosmological theories describing the formation of this web are fairly good at predicting the position and size of modern galaxies, but recently scientists have discovered several serious discrepancies. For example, near our Galaxy, they found an unusual structure, the "Great Repulsive", where there is practically no visible matter. Moreover, it was later revealed that the Milky Way is also located inside the "zone of emptiness", where space can expand faster than in other areas of the Universe.
Furlanetto and his colleagues accidentally discovered another such anomaly, observing with the Subaru telescope the oldest galaxies located about 12 billion light-years from Earth. Astronomers, as Furlanetto notes, have long wondered why the ultraviolet radiation of the brightest and hottest stars in the early Universe (the so-called Lyman glow) is extremely inhomogeneously distributed over the night sky.
There can be two explanations for this. On the one hand, it is quite possible that galaxies and matter were not scattered across the universe as uniformly as the theory shows. On the other hand, some objects or processes can interfere with the movement of the light of these stars, which makes it seem to us that certain parts of the Universe were darker than they really are.
Furlanetto and his colleagues tested these theories by observing such a "hole" in the Lyman glow, located at the junction of the constellations Cetus, Pisces and Aries. With the help of Subaru, scientists have counted the number of quasars (active galactic nuclei) and determined the strength of their ultraviolet glow.
It turned out that in this sector of space there are quite a few large and active galaxies - about two to three times less than predicted by classical cosmology. That is, this corner of the Universe produced unusually little Lyman glow because it was a "cosmic desert" - there were almost no galaxies, stars and other clusters of ordinary matter in it.
Promotional video:
Why the "space desert" appeared, scientists cannot yet say. Nevertheless, its discovery, according to Furlanetto, imposes serious restrictions on theories describing the formation of the "web of the universe" and how matter was distributed along its threads. Further observations of this area and other similar objects, scientists hope, will help to understand what gave rise to it and how modern theories of the evolution of the universe should be changed.
