APOD: Simulation TNG50: A Galaxy Cluster Forms (2022 May 29)

[APOD Robot]

Simulation TNG50: A Galaxy Cluster Forms

Explanation: How do clusters of galaxies form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. A recent effort is TNG50 from IllustrisTNG, an upgrade of the famous Illustris Simulation. The first part of the featured video tracks cosmic gas (mostly hydrogen) as it evolves into galaxies and galaxy clusters from the early universe to today, with brighter colors marking faster moving gas. As the universe matures, gas falls into gravitational wells, galaxies forms, galaxies spin, galaxies collide and merge, all while black holes form in galaxy centers and expel surrounding gas at high speeds. The second half of the video switches to tracking stars, showing a galaxy cluster coming together complete with tidal tails and stellar streams. The outflow from black holes in TNG50 is surprisingly complex and details are being compared with our real universe. Studying how gas coalesced in the early universe helps humanity better understand how our Earth, Sun, and Solar System originally formed.

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[Ann]

It's Mother's Day in Sweden, so I guess I could see today's video as a tribute to the cosmic gas that isn't just the mother of all galaxies, but it's the mother of us all.

Of course, the gas itself is the "child" of the Big Bang, and some people think that the Big Bang is the "child" of inflation, so...

Well, Happy Mother's Day if you happen to be in Sweden, cosmic gas, Big Bang and inflation.

Ann

[John Douma]

Hello,

I have never posted here before but I have been following the picture of the day for years. In simulation videos such as this one, I would get a lot more out of it if you replaced the music with a narration explaining what is happening when. It is difficult to correlate the paragraph below with the video.

I would be interested to know how others feel about this. My point of view comes from a desire to understand what I am watching but I can understand how others may see the video as a work of art and prefer the music.

Thanks,

John

[Spif]

Sometimes I like to set up some lawn chairs out back and watch these go off.

You know, like on weekends.

[johnnydeep]

Hello,

I have never posted here before but I have been following the picture of the day for years. In simulation videos such as this one, I would get a lot more out of it if you replaced the music with a narration explaining what is happening when. It is difficult to correlate the paragraph below with the video.

I would be interested to know how others feel about this. My point of view comes from a desire to understand what I am watching but I can understand how others may see the video as a work of art and prefer the music.

Thanks,

John

I agree that a voice-over - plus some annotations and arrows pointing at specific things - would be helpful. The video is from the APOD YouTube channel so that at least could have been done. Of course, that would take a lot more time and effort and there is not an unlimited supply of that. I tried to find the same video at the TNG media link (https://www.tng-project.org/media/), but failed(*). I thought there might be more explanation to be had there.

(*) EDIT: ok, here's the original silent video - https://www.tng-project.org/movies/tng/ ... _1080p.mp4. It's a few seconds longer and that made me exclude it. And here's the text explanation for it:

The motion of cosmic gas in a small region of TNG50, color encoding velocity from at rest (black) to 1000 km/s (bright red and white). At early times, accretion and infall from the intergalactic medium coallesces in the centers of many small halos. Stellar feedback produces slow galactic winds which gradually push mass outwards, until several central blackholes become sufficiently massive to launch high-velocity outflows to large distance. Past redshift one, we switch to a view of the stellar distribution of this forming protocluster, revealing the process of the hierarchical assembly of structure and its signatures: stellar streams, shells, tidal tails, and merging galaxies. The binary coallesence of the two galactic nuclei occurs at z=0.15, sending spiral waves outwards into the ICL.

[orin stepanek]

This galaxy;NGC1672 is Oh so beautiful!
It is nice to have these videos as they are always interesting and
informative! We really don't know for sure and it is an educated
guess at best! How ever; keep them coming; I really like them!

[EuropaVisitor]

The motion of cosmic gas in a small region of TNG50, color encoding velocity from at rest (black) to 1000 km/s (bright red and white). At early times, accretion and infall from the intergalactic medium coallesces in the centers of many small halos. Stellar feedback produces slow galactic winds which gradually push mass outwards, until several central blackholes become sufficiently massive to launch high-velocity outflows to large distance. Past redshift one, we switch to a view of the stellar distribution of this forming protocluster, revealing the process of the hierarchical assembly of structure and its signatures: stellar streams, shells, tidal tails, and merging galaxies. The binary coallesence of the two galactic nuclei occurs at z=0.15, sending spiral waves outwards into the ICL.

Does that mean the area which gas seems to be spurting out of (on the right starting at around z=1.8) is probably a black hole?

[johnnydeep]

The motion of cosmic gas in a small region of TNG50, color encoding velocity from at rest (black) to 1000 km/s (bright red and white). At early times, accretion and infall from the intergalactic medium coallesces in the centers of many small halos. Stellar feedback produces slow galactic winds which gradually push mass outwards, until several central blackholes become sufficiently massive to launch high-velocity outflows to large distance. Past redshift one, we switch to a view of the stellar distribution of this forming protocluster, revealing the process of the hierarchical assembly of structure and its signatures: stellar streams, shells, tidal tails, and merging galaxies. The binary coallesence of the two galactic nuclei occurs at z=0.15, sending spiral waves outwards into the ICL.

Does that mean the area which gas seems to be spurting out of (on the right starting at around z=1.8) is probably a black hole?

I would say yes. Notice that it's spewing gas symmetrically from radially opposite points, which is the typical way that BHs behave.

[heehaw]

Hello,

I have never posted here before but I have been following the picture of the day for years. In simulation videos such as this one, I would get a lot more out of it if you replaced the music with a narration explaining what is happening when. It is difficult to correlate the paragraph below with the video.

I would be interested to know how others feel about this. My point of view comes from a desire to understand what I am watching but I can understand how others may see the video as a work of art and prefer the music.

Thanks,

John

Welcome, John (if I may ! ). You might also enjoy my page https://henry.pha.jhu.edu/rch.html
Cheers, Heehaw !