by Ann » Thu Jan 26, 2023 7:52 am
MarkBour wrote: ↑Thu Jan 26, 2023 6:17 am
Intuitively, bigger, stronger, more violent, should be somehow more terrifying. This "active galaxy" is so far beyond that, the mental image of it does not connect to my emotions. And yet I wonder. In its past, it has perhaps extinguished entire civilizations, even some that could have been space-faring on a scale we can scarcely conceive.
Unlike you, Mark, I do find NGC 1275 impressive.
I'm intrigued by the filamentary nature of the debris of the merger process of NGC 1275.
Hubblesite.org wrote about NGC 1275:
Long gaseous filaments stretch out beyond the galaxy, into the multimillion-degree, X-ray-emitting gas that fills the cluster.
These filaments are the only visible-light manifestation of the intricate relationship between the central black hole and the surrounding cluster gas. They provide important clues about how giant black holes affect their surrounding environment...
The amount of gas contained in a typical thread is around one million times the mass of our own Sun. They are only 200 light-years wide, are often very straight, and extend for up to 20,000 light-years. The filaments are formed when cold gas from the core of the galaxy is dragged out in the wake of the rising bubbles blown by the black hole.
It has been a challenge for astronomers to understand how the delicate structures withstood the hostile, high-energy environment of the galaxy cluster for over 100 million years. They should have heated up, dispersed, and evaporated by now, or collapsed under their own gravity to form stars.
A new study published in the August 21 Nature magazine proposes that magnetic fields hold the charged gas in place and resist the forces that would distort the filaments. This skeletal structure is strong enough to resist gravitational collapse.
It is interesting to compare NGC 1275, at some 230 million light years, with
Centaurus A, which is another example of a galaxy merger, but at a distance of only some 10-16 million light-years.
I find it interesting that Cen A displays a very strong jet in X-rays, but no jet can be seen in NGC 1275. The blue filament seen near the center of NGC 1275 is not a jet, but
the distorted remnants of the hapless spiral galaxy that collided with the large elliptical galaxy of NGC 1275. However, both Cen A and NGC 1275 display large "
Fermi bubbles", huge X-ray bubbles, on opposite sides of the central black hole.
Admittedly, in NGC 1275 the "Fermi bubbles" look more like cavities blown in the surrounding X-ray ambiance.
Finally, let's hear NGC 1275 sing to us (at 57 octaves below middle C)!
Click to play embedded YouTube video.
Ann
[quote=MarkBour post_id=328755 time=1674713847 user_id=141361]
Intuitively, bigger, stronger, more violent, should be somehow more terrifying. This "active galaxy" is so far beyond that, the mental image of it does not connect to my emotions. And yet I wonder. In its past, it has perhaps extinguished entire civilizations, even some that could have been space-faring on a scale we can scarcely conceive.
[/quote]
Unlike you, Mark, I do find NGC 1275 impressive.
[float=left][img3="Active Galaxy NGC 1275. Image Credit: NASA, ESA, Hubble Heritage, A. Fabian (University of Cambridge, UK)"]https://apod.nasa.gov/apod/image/2301/ngc1275_heic0817a_1024.jpg[/img3][/float][float=right][img3="Galaxies of the Perseus Cluster. Note how NGC 1275 stands out with its pink color and filaments sticking out of it. Credit & Copyright: R. Jay Gabany"]https://apod.nasa.gov/apod/image/0905/PerseusCluster_gabany_abell426H600.jpg[/img3][/float]
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I'm intrigued by the filamentary nature of the debris of the merger process of NGC 1275.
[quote][url=https://hubblesite.org/contents/news-releases/2008/news-2008-28.html]Hubblesite.org[/url] wrote about NGC 1275:
Long gaseous filaments stretch out beyond the galaxy, into the multimillion-degree, X-ray-emitting gas that fills the cluster.
These filaments are the only visible-light manifestation of the intricate relationship between the central black hole and the surrounding cluster gas. They provide important clues about how giant black holes affect their surrounding environment...
The amount of gas contained in a typical thread is around one million times the mass of our own Sun. They are only 200 light-years wide, are often very straight, and extend for up to 20,000 light-years. The filaments are formed when cold gas from the core of the galaxy is dragged out in the wake of the rising bubbles blown by the black hole.
It has been a challenge for astronomers to understand how the delicate structures withstood the hostile, high-energy environment of the galaxy cluster for over 100 million years. They should have heated up, dispersed, and evaporated by now, or collapsed under their own gravity to form stars.
[b][color=#FF00FF]A new study published in the August 21 Nature magazine proposes that magnetic fields hold the charged gas in place and resist the forces that would distort the filaments[/color][/b]. This skeletal structure is strong enough to resist gravitational collapse.[/quote]
It is interesting to compare NGC 1275, at some 230 million light years, with [url=https://www.eso.org/public/images/eso0005b/]Centaurus A[/url], which is another example of a galaxy merger, but at a distance of only some 10-16 million light-years.
[float=left][img3="NGC 1275 (Perseus A) in X-rays. Note the small blue filaments near the center of NGC 1275. Credit: NASA/CXC/IoA/A.Fabian et al."]https://upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Central_regions_Perseus_galaxy_cluster.jpg/1024px-Central_regions_Perseus_galaxy_cluster.jpg[/img3][/float][float=right][img3="Centaurus A in X-rays. Credit: Chandra."]https://chandra.harvard.edu/photo/2014/cena/cena_525.jpg[/img3][/float]
[clear][/clear]
I find it interesting that Cen A displays a very strong jet in X-rays, but no jet can be seen in NGC 1275. The blue filament seen near the center of NGC 1275 is not a jet, but [url=https://science.nasa.gov/filaments-active-galaxy-ngc-1275]the distorted remnants[/url] of the hapless spiral galaxy that collided with the large elliptical galaxy of NGC 1275. However, both Cen A and NGC 1275 display large "[url=https://fermi.gsfc.nasa.gov/science/constellations/pages/bubbles.html]Fermi bubbles[/url]", huge X-ray bubbles, on opposite sides of the central black hole.
Admittedly, in NGC 1275 the "Fermi bubbles" look more like cavities blown in the surrounding X-ray ambiance.
Finally, let's hear NGC 1275 sing to us (at 57 octaves below middle C)! :D
[youtube]https://www.youtube.com/watch?v=FMifNQ7MFMU[/youtube]
Ann