Optical image of the Bell Bell 3391/95 system taken with a DCM camera. The superimposed is the erosita image (darker = higher gas density) and the radio profile of the ASKAP telescope (yellow). Credit: Reprich et al., Astronomy and Astrophysics
More than half the matter in our universe is still hidden from us. However, astrophysicists may have it where it may be: in so-called filaments, numerous giant thread-like structures of gas that surround and connect galaxies and galaxy clusters. A team led by Bonn University has now observed for the first time a gas filament with a length of one million light years. Its design is similar to that of computer simulation predictions. So observation also confirms our ideas about the origin and evolution of our universe. The results are published in the journal Astronomy and Astrophysics.
We have a small attitude towards our existence. Exactly exactly 13.8 billion years ago, this The Big Bang Came. It is the beginning of space and time, but also of all the things that make up our universe today. Although initially it was centered at one stage, it expanded at a tremendous speed – a huge gas cloud in which matter was distributed almost evenly.
Almost, but not completely: in some parts the cloud was a little smaller than others. And for this reason there are planets, stars and galaxies today. This is because slightly higher gravitational forces have been used in the humid areas, which led the surrounding air towards them. So more and more things focus on these regions over time. Yet the space between them became harder and stronger. During the good 13 billion years, a kind of sponge structure evolved: large “holes” without matter, between areas where thousands of galaxies gather in small space, in so-called galaxy clusters.
A still image of the simulation showing the distribution of hot gas (left) compared to the erosita X-ray image of the Able 3391/95 system (right). Credit: Reprich et al., Astronomy and Astrophysics
Fine web of gas threads
If it really happened that way, galaxies and clusters should still be connected by the remnants of this gas, such as the gossymor-thin threads of the spider web. “According to calculations, more than half of all baryonic objects in our universe are contained in these filaments – these are the forms in which the stars and planets are formed, just as we are ourselves,” said Prof. Dr. Tho. Thomas Reprich explains. Argelander Institute for Astronomy at Bonn University. Yet it has escaped our notice so far: due to the enormous expansion of the fibers, their mass is extremely thin: it contains only ten particles per cubic meter, which is less than what we can create an excellent vacuum on Earth.
However, with the new measuring instrument, the Erosita Space Telescope, Riprich and his colleagues were now able to make the gas fully visible for the first time. “Erosita has a very sensitive detector for the type of X-ray radiation that emanates from the gas in the rela,” explains Raprich. “It also has a large field of view – like a wide angle lens, it captures a relatively large amount of sky in a single size and at a very high resolution.” This allows you to take detailed images of large objects, such as filaments, in a relatively short time.
This view of the Erosita image (right; simulation for comparison) also shows very obscure areas of thin gas. Credit: Remaining: Reprich et al., Space Science Reviews, 177, 195; Right: Reprich et al., Astronomy and Astrophysics
Confirmation of the standard model
In their study, researchers examined a celestial body called Abel 3391/95. This is a system of three galaxy clusters, about 700 million light years away from us. Erosita images show not only clusters and numerous individual galaxies, but also gas filaments connecting these structures. The entire filament is 500 million light years long. But it could be even more formidable: scientists assume the images show only one section.
“We compared our observations with the results of simulations recreating the evolution of the universe,” explains Reprich. “Erosita images are surprisingly like computer-generated graphics. This suggests that the widely accepted standard model for the evolution of the universe is appropriate. “Most importantly, the data shows that the missing thing is actually hidden in the filaments.
Reprich is also a member of the Transdisciplinary Research Area (TRA) “Building Blocks of Matter and Basic Interaction” at Bonn University. In six different TRAs, scientists from the most diverse disciplines and disciplines come together to work collaboratively on the future-related research topics of University Excellence.
Reference: “Abel 3391/95 Galaxy Cluster System. A 15 MPC intergalactic medium emission filament, hot gas bridge, fulfilling matter clams and (re) acceleration Plasma S.R.G. / Erosita data to SKP. / E.M.U. And D.K.M. Finding paired data, TH Riprich, A. Veronica, F. Pakod, M.E. Ramos-Seja, N. Ota, J. Sanders, M. Cara, T. Erben, et al., Accepted, Astronomy and Astrophysics.
DOI: 10.1051 / 0004-6361 / 202039590
Participating organizations and funding:
The study involved about 50 scientists from institutes in Germany, USA, Switzerland, ND, Chile, Australia, Australia, Spain, South Africa and Japan.
Developed with funding from the Erosita Max Planck Society and the German Aerospace Center (DLR). Last year a telescope was launched into space sitting on a Russian-German satellite, the construction of which was supported by the Russian space agency Roscosmos. The work includes the Sector Tolo Lolo Inter-American Observatory, NSF’s NORLAB program, and the Australian Australian Square Kilometer Array Pathfinder (ASKAP) telescope, built and operated by Vector M. The Blanco 4-meter telescope also used a dark energy camera (DECAM). By CSIRO (Commonwealth Scientific and Industrial Research Institute). The current study was funded by a number of research funding organizations in the participating countries.
