Researchers monitor dark objects that determine the origin, global evolution

To date, over 50% of the case in the universe has been invisible to humans. But astronomers had an idea of ​​where it could be located: In confirmed filaments, fibrous-like structures of hot gas surround and connect galaxies and assemblages of galaxies.

Image still from simulation showing hot gas circulation (left), compared to eROSITA X-ray image of Abell 3391/95 system (right).
Image still from simulation showing hot gas circulation (left), compared to eROSITA X-ray image of Abell 3391/95 system (right). Image credit: (c) Reiprich et al., Astronomy & Astrophysics.

Now, for the first time, a group of researchers, led by the University of Bonn, have discovered a gas filament, whose length extends to 50 million light-years. The structure of this gas filament is very similar to the prediction of computer simulations.

Thus, the observation also confirms the concepts related to the origin and evolution of the universe. The findings of the study were published in the Astronomy & Astronomy iris.

Mankind is under the influence of a small anomaly. The Big Bang happened nearly 13.8 billion years ago. He built the beginning of time and space and also everything that makes up the universe today. Although the Big Bang was initially targeted at one point, it expanded at an alarming rate – a huge gas cloud, where the issue was spread almost evenly.

Almost, but not entirely: the cloud was in some parts slightly denser than in others. It is for this single reason that galaxies, stars and planets exist today. The reason for this is that the denser areas applied slightly higher gravitational forces, which drew the gas from the surrounding areas.

As a result, more and more cases in these areas accumulated over time. But the space between these regions became increasingly empty. Over a good 13 billion years, a kind of sponge structure emerged – that is, large ‘holes’ that were not large enough, separated by regions where an unlimited number of galaxies, the so-called galaxy assemblages, are gathered in it. instead of a tiny little place.

Fine Nets of Gas Threads

If it happened that way, the collections and galleries still need to be connected to the remnants of gas, like the gossamer-thin threads of spider webs.

According to calculations, more than half of the baryonic matter in our universe is contained in these filaments – this is the kind of object on which stars and planets are made, as we are.

Dr. Thomas Reiprich, Professor, Argelander Institute for Astronomy, University of Bonn

But so far, he has kept a close eye on people – due to the large expansion of the filaments, they contain a dilute substance. In this case there are only 10 particles per cubic meter, which is roughly less than the best vacancy that can be produced on Earth.

But now with the help of the eROSITA space telescope – a novel measuring instrument – Reiprich and his colleagues were able to see the gas completely for the first time.

EROSITA is a highly sensitive detector for the type of X-ray radiation emitted by the gas in filaments. It also has a panoramic view – like a wide-angle lens, it captures a relatively large part of the sky in one dimension, and at a very high resolution..

Dr. Thomas Reiprich, Professor, Argelander Institute for Astronomy, University of Bonn

This allows scientists to take deep images of such large objects, as the filaments, in a very short time.

Demonstration of the standard model

In their analysis, the researchers analyzed a celestial object called Abell 3391/95. There are three galaxy orbits in this system, which is about 700 million light-years away from Earth.

The images taken with the eROSITA space telescope revealed not only the various galaxies and individual assemblages, but also showed the gas filaments that bind these structures. The total length of the filament is 50 million light-years; however, it may be much larger: According to the researchers, these images show only a segment.

We compared our observations with the results of a simulation that recreates the evolution of the universe. The eROSITA images are very similar to computer generated graphics. This suggests that the generally accepted conventional model for global evolution is correct.

Dr. Thomas Reiprich, Professor, Argelander Institute for Astronomy, University of Bonn

More importantly, the data show that the lost material appears to be hidden in the filaments.

Reiprich is also a member of the Interdisciplinary Research Area (TRA) “Building blocks of matter and basic interaction” at the University of Bonn. In six different TRA, researchers from the most diverse disciplines and faculties collaborate to collaborate on relevant University of Excellence research topics.

Partner Institutions and Funding

The study included nearly 50 researchers from institutions in the United States, Germany, Switzerland, South Africa, Spain, Australia, Japan and Chile.

The eROSITA space telescope was designed with financial support from the Max Planck Society and the German Aerospace Center (DLR). In 2019, the telescope was launched into space aboard a Russian-German satellite, and the construction was funded by the Russian space agency Roskosmos.

The study also utilized the Dark Power Camera (DECam) on the Víctor M. Blanco 4-m Telescope installed at the Cerro Tololo Inter-American Observatory, NSF’s NOIRLab program, and the Array Pathometer Array Telescope (ASKAP). ) Australia. , built and operated by the Commonwealth Scientific and Industrial Research Organization (CSIRO). The new study received financial support from many research funding organizations in the participating countries.

Magazine Information:

Reiprich, TH, et al. (2020) Abell 3391/95 galaxy browser system. 15 Mpc intergalactic diffusion filament, warm gas bridge, infalling material lumps, and (re-) accelerated plasma detected by combining SRG / eROSITA data with ASKAP / EMU and DECam data. Astronomy & Astronomy.