A gas filament 50 million light-years long – inscrutably large thread-like structures of hot gas that surround and connect galaxies and galaxy clusters – was first observed by astronomers at the University of Bonn. The structure is eerily similar to the predictions of recent computer simulations.
“A Tiny Aberration”
We owe our existence to a minor deviation, reports the University of Bonn. Over the course of 13 billion years, since the Big Bang, “a kind of sponge structure developed: big” holes. ” without any matter, with intermediate regions where thousands of galaxies gather in a small space, so-called clusters of galaxies, which should still be connected by remaining filaments of the primordial gas, like the gossamer threads of a spider web.
“According to calculations, more than half of all baryonic matter in our universe resides in these filaments – this is the form of matter that makes up stars and planets, just like us,” explains Dr. Thomas Reiprich of the Argelander Institute. for astronomy at the University of Bonn. Yet so far it has escaped our sight: due to the enormous expansion of the filaments, the matter in it is extremely diluted: it contains only ten particles per cubic meter, which is far less than the best vacuum we can create on Earth. “
Giant filaments fed the universe we see today
Contrary to the earlier view that galaxies formed and then organized into clusters, from below, it is now widely believed that gigantic filaments in the universe fueled the formation of galaxies and galaxies in places where the filaments intersected, creating regions of matter.
2019 study from the RIKEN Cluster for Pioneering Research and the University of Tokyo – used observations from the Multi Unit Spectroscopic Explorer (MUSE) of the ESO Very Large Telescope (VLT) in Chile and the Suprime-Cam of the Subaru telescope to provide detailed Observe the filaments of gas connecting galaxies in a large, distant protocluster in the early Universe. – suggests that gas that fell along massive filaments under gravity in the early Universe caused the formation of starburst galaxies and supermassive black holes, the universe structure we see today.
“Gargantuan Filaments” – Incubators of supermassive black holes in the early cosmos
Enter eRosita
With a new instrument, the eROSITA space telescope, Reiprich and his colleagues were able to make the gas fully visible for the first time. “EROSITA has highly sensitive X-ray detectors from the gas in filaments,” explains Reiprich of cluster Abell 3391/95 – a system of three galaxy clusters about 700 million light-years away. The eROSITA images show not only the clusters and numerous individual galaxies, but also the gas filaments connecting these structures. The entire filament is 50 million light years long. But it could be even more massive: the scientists assume that the images show only part of it. “It also has a large field of view – like a wide-angle lens, it captures a relatively large part of the sky in a single measurement. , and with a very high resolution. “This allows detailed images to be made of such enormous objects such as filaments in a relatively short time.
In this representation of the eROSITA image (right; left another simulation for comparison), very faint areas of thin gas are also visible. Credit: Left: Reiprich et al., Space Science Reviews, 177, 195; right: Reiprich et al., Astronomy & Astrophysics
Confirmation of the standard model
“We compared our observations with the results of a simulation that reconstructs the evolution of the Universe,” explains Reiprich. “The eROSITA images look remarkably like computer-generated images. This suggests that the generally accepted standard model for the evolution of the universe is correct. Most importantly, the data shows that the missing matter is probably actually hidden in the filaments.
Source: TH Reiprich et al. The Abell 3391/95 cluster system of galaxies. A 15 Mpc intergalactic medium emission filament, a warm gas bridge, clumping matter and (re) accelerated plasma discovered by combining SRG / eROSITA data with ASKAP / EMU and DECam data, Astronomy & Astrophysics (2020). DOI: 10.1051 / 0004-6361 / 202039590
The Daily Galaxy, Max Goldberg, via University of Bonn
Image Credit: At the top of the page shows a detailed computer simulation of the complex structure of the cosmic web. Long filaments of dark matter (blue) connect nodes of galaxies and clusters of galaxies (pink), while gas (orange) penetrates them. By modeling and observing the cosmic web, researchers gain insights into the structure and evolution of the early universe. Credit to the Illustris Collaboration