Galaxy clusters caught in a first kiss

galaxy
Credit: CC0 Public Domain

For the first time, astronomers have found two giant clusters of galaxies that are just about to collide. This observation can be seen as a missing 'piece of the puzzle' in our understanding of the formation of structure in the universe, since large-scale structures—such as galaxies and clusters of galaxies—are thought to grow by collisions and mergers. The result was published in Nature Astronomy.

Clusters of galaxies are the largest known bound objects and consist of hundreds of that each contain hundreds of billions of stars. Ever since the Big Bang, these objects have been growing by colliding and merging with each other. Due to their large size, with diameters of a few million light years, these collisions can take about a billion years to complete. After the dust has settled, the two colliding clusters will have merged into one bigger cluster.

Because the merging process takes much longer than a human lifetime, we only see snapshots of the various stages of these collisions. The challenge is to find colliding clusters that are just at the stage of first touching each other. In theory, this stage has a relatively short duration and is therefore hard to find. It is like finding a raindrop that just touches the water surface in a photograph of a pond during a rain shower. Obviously, such a picture would show a lot of falling droplets and ripples on the water surface, but only few droplets in the process of merging with the pond. Similarly, astronomers found a lot of single clusters and merged clusters with outgoing ripples indicating a past collision, but until now no two clusters that are just about to touch each other.

An international team of astronomers have now announced the discovery of two clusters on the verge of colliding. This enabled astronomers to test their , which show that in the first moments a shock wave is created in between the clusters and travels out perpendicular to the merging axis. "These clusters show the first clear evidence for this type of merger shock," says first author Liyi Gu from RIKEN national science institute in Japan and SRON Netherlands Institute for Space Research. "The shock created a hot belt region of 100-million-degree gas between the clusters, which is expected to extend up to, or even go beyond the boundary of the giant clusters. Therefore the observed shock has a huge impact on the evolution of galaxy clusters and large scale structures."

Astronomers are planning to collect more 'snapshots' to ultimately build up a continuous model describing the evolution of mergers. SRON-researcher Hiroki Akamatsu: "More merger clusters like this one will be found by eROSITA, an X-ray all-sky survey mission that will be launched this year. Two other upcoming X-ray missions, XRISM and Athena, will help us understand the role of these colossal merger shocks in the structure formation history."

Liyi Gu and his collaborators studied the colliding pair during an observation campaign, carried out with three X-ray satellites (ESA's XMM-Newton satellite, the NASA's Chandra satellite, and JAXA's Suzaku satellite) and two (the Low-Frequency Array, a European project led by the Netherlands, and the Giant Metrewave Radio Telescope operated by National Centre for Radio Astrophysics of India).


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More information: Observations of a pre-merger shock in colliding clusters of galaxies, Nature Astronomy (2019). DOI: 10.1038/s41550-019-0798-8 , https://www.nature.com/articles/s41550-019-0798-8
Journal information: Nature Astronomy

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Citation: Galaxy clusters caught in a first kiss (2019, June 24) retrieved 18 July 2019 from https://phys.org/news/2019-06-galaxy-clusters-caught.html
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Jun 24, 2019
The plasma ignoramuses have detected a galactic scale double layer forming between the two interacting galaxies, too bad they don't understand the plasma processes involved so they can properly describe what is and predict what could happen.

Jun 24, 2019
The necessity of the Computer Simulation:
"..astronomers have now announced the discovery of two clusters on the verge of colliding. This enabled astronomers to test their computer simulations, which show that in the first moments a shock wave is created in between the clusters and travels out perpendicular to the merging axis. "These clusters show the first clear evidence for this type of merger shock,"

"The shock created a hot belt region of 100-million-degree gas between the clusters, which is expected to extend up to, or even go beyond the boundary of the giant clusters. Therefore the observed shock has a huge impact on the evolution of galaxy clusters and large scale structures."


In the absence of an actual Event to witness and record, Computerised Simulations have to suffice, since it is inconvenient to wait around for a possible thousands or millions of Earth years for the original event to happen in this region, where only future AI will know of it.

Jun 24, 2019
Is there a possibility that there is a 'ridge of radio emissions' as well as Magnetic Fields, similar to the one in:

https://phys.org/...ers.html

Jun 24, 2019
In publications [1-3] a new cosmological paradigm was proposed. The picture of the birth of stars and galaxies resulting from this paradigm was also presented in [4, 5]. In [6] a hypothesis was proposed about the origin of the jets and outflows from stars and galaxies. A new generation of ground and orbital astronomical instruments rapidly increased the sensitivity and resolution of observations. In this paper, an attempt is made to analyze the latest observations from the point of view of a new paradigm.
https://www.acade...rvations

Jun 24, 2019
The real question to be answered is how do galactic clusters collide with one another in a so-called expanding Universe? Mind you, we're not talking about TWO individual galaxies as will happen with the MW & Andromeda some billions of years down the road.

The Biggo Bango in action huh? The Infinite Universe of Pop-Cosmology fantasy has no room for these galaxy clusters, is that it?


Jun 25, 2019
cantcope,
you are properly described as a victim of cheap-drug induced hallucinations.
i predict you will repeat the same nonsense you have been
babbling for years.
without any effort on your part to learn from the new data & evolving knowledge base.

sillyegghead, gluing a couple of toy magnets to your forehead?
will not replace the electro-shock treatments prescribed for your pathology.

i gotta wonder at the administrators for this site? allowing you to denounce honest scientists with your ignorant diatribes.
considering your complete incompetency at any understanding of their work?

ohh benni, all those years of your crapulous comments have fossilized you into coprolite!

simple answers to your simpleton questions.

q: how do galactic clusters collide with one another in a so-called expanding Universe?

ans: random chance. the drunkard's walk.

q: has no room for these galaxy clusters, is that it?

ans: yes

benni. you have a childish notion of the dimensions of SpaceTime.

Jun 25, 2019
: how do galactic clusters collide with one another in a so-called expanding Universe?

ans: random chance
........14 billion years worth of expansion at mind boggling velocities & these galaxies clusters are still no further apart than when they first came into existence? In fact they're even closer than when they came into existence.

Random chance is everything your love for Pop-Cosmology fantasy is all about, try studying the 2nd Law of Thermodynamics to gain at least a small semblance of education as to why your "random chance" is so far beyond statistical probability as to be beyond anything resembling reality.

Jun 25, 2019
benni. you have a childish notion of the dimensions of SpaceTime.
.......by comparison that is way more than you have, you have never demonstrated even the smallest modicum of comprehension of the 2nd Law of Thermodynamics, ENTROPY, or even heard of the concept until you started reading Benni's Comments. Keep reading them, you'll learn more than what you thought possible.

Jun 25, 2019
The plasma ignoramuses have detected a galactic scale double layer forming between the two interacting galaxies, too bad they don't understand the plasma processes involved so they can properly describe what is and predict what could happen.


Lol. What a load of unscientific crap. Stop making things up, woo boy.

Jun 25, 2019
benni. you have a childish notion of the dimensions of SpaceTime.
.......by comparison that is way more than you have, you have never demonstrated even the smallest modicum of comprehension of the 2nd Law of Thermodynamics, ENTROPY, or even heard of the concept until you started reading Benni's Comments. Keep reading them, you'll learn more than what you thought possible.


Says the idiot that doesn't know what a half-life is, and can't even do basic arithmetic. As proven. Clown.

Jun 25, 2019
we're given these little picys from the article's advert figure column:

media.springernature.com/m312/springer-static/image/art%3A10.1038%2Fs41550-019-0798-8/MediaObjects/41550_2019_798_Fig1_HTML.png

media.springernature.com/m312/springer-static/image/art%3A10.1038%2Fs41550-019-0798-8/MediaObjects/41550_2019_798_Fig2_HTML.png

media.springernature.com/m312/springer-static/image/art%3A10.1038%2Fs41550-019-0798-8/MediaObjects/41550_2019_798_Fig3_HTML.png

(these won't link directly in forum because they don't start with www)

and no picy tease of the simulation shock wave. What I'm wondering is where do the shock waves extrude. Do they extrude out into intergalactic space primarily or is there more? Yes, I know it's just a simulation of course.

Jun 25, 2019
@Renfield;

The discovery of equatorial shock completes the inventory of merger shocks. It reveals an important merging epoch right before the core collision, when shocks are formed at the contact interface and propagate vertically to the merger axis. Here we measured the energy release by the equatorial shock, which may prove to be one of the important dissipation processes of major mergers. As shown in the numerical simulations, equatorial shocks have the highest velocity among merger shocks, allowing them to reach large distance (≥3 Mpc) before they disappear. These shocks, together with some axial shocks that form later, might dump a significant portion of the kinetic energy beyond the cluster boundary, providing a feasible way to heat the inter /circum-galactic medium in the cluster surroundings.


From the letter.

Jun 25, 2019
Clusters of galaxies in collision

Clusters of galaxies
Are the largest known bound objects
And consist of hundreds of galaxies
That each
Contain hundreds of billions of stars
Ever since the Big Bang
These objects have been growing
By colliding and merging with each other
For clusters of galaxies
Clusters of galaxies in collision
Is proof
These galaxies
Are not
Receding in this vacuous galactic universe vacuum
For
Recession implies the reverse of clustering
Implies the reverse of clusters in collision
Implies the reverse of these trillions of galaxies increasing their mass
for all the evidence points to these trillions of galaxies
Collapsing
For these galaxies are orbitaly combing
This receding theory
Is an attempt
To prove Georges Lemaitre's Lord's view
A religious beginning
For Georges Lemaitre wrote nothing about galaxies combing in clumps
For
Georges Lemaitre did not have the telescopes
That we have to day

Jun 25, 2019
@Benni
@granville
@CD85
benni. you have a childish notion of the dimensions of SpaceTime.
.......by comparison that is way more than you have, you have never demonstrated even the smallest modicum of comprehension of the 2nd Law of Thermodynamics, ENTROPY, or even heard of the concept until you started reading Benni's Comments. Keep reading them, you'll learn more than what you thought possible.
says Benni

There is no such object as TIME in Spacetime. Have you forgotten? There are 3 dimensions of Space that is surrounded by the Vacuum, and the 4th dimension is of the Mind. The MIND, Benni.
The 5th dimension is what the Mind creates. That is all I will reveal of it. Please don't forget.

Jun 25, 2019
There is no such object as TIME in Spacetime. Have you forgotten?
....nope, haven't forgotten.

There are 3 dimensions of Space that is surrounded by the Vacuum, and the 4th dimension is of the Mind. The MIND, Benni.
....so what you're trying to put across is that the mind can span the chasm between the 3rd & 4th dimension?

The 5th dimension is what the Mind creates. That is all I will reveal of it. Please don't forget.
.............Differential Equations?

Jun 25, 2019
There is no such object as TIME in Spacetime. Have you forgotten?
....nope, haven't forgotten.

There are 3 dimensions of Space that is surrounded by the Vacuum, and the 4th dimension is of the Mind. The MIND, Benni.
....so what you're trying to put across is that the mind can span the chasm between the 3rd & 4th dimension?

The 5th dimension is what the Mind creates. That is all I will reveal of it. Please don't forget.
.............Differential Equations?
says Benni

Yes. Yes, of course. It is all a Game, Benni. A wonderful Cosmic Game. As I told danR, there are things that humans and other intelligent beings in the Cosmos are not allowed to discover/know. But humans and the others have the Tools to search and discover all the things that are discoverable. But a few other things are forbidden to be known. It is the Law.

Jun 25, 2019
There are 3 dimensions of Space that is surrounded by the Vacuum, and the 4th dimension is of the Mind. The MIND, Benni.
....so what you're trying to put across is that the mind can span the chasm between the 3rd & 4th dimension?
=================

Benni, what do you think has been happening all these thousands of Earth years? Humans have been spanning that Chasm - or at least trying. It has been touch and go. But the Mind is improving - except for such as rrwillsj, of course. LOL

Jun 26, 2019
There are 3 dimensions of Space that is surrounded by the Vacuum, and the 4th dimension is of the Mind. The MIND, Benni.
....so what you're trying to put across is that the mind can span the chasm between the 3rd & 4th dimension?
=================

Benni, what do you think has been happening all these thousands of Earth years? Humans have been spanning that Chasm - or at least trying. It has been touch and go. But the Mind is improving -
.......no one has been in touch with my mind spanning knowledge gaps & chasms. I'm far & away beyond the average person, not because I'm into mind reading but because my knowledge of the physical sciences have presented me with unique insight that many would mis-interpret as spiritual.

I've had a couple of instances in which a person told me they could read snippets of what was on my mind. So I gave them a test & told them I could put up BLOCKAGE to their mind reading attempts, they backed off in fear when I told them that.

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