APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

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APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by APOD Robot » Sun Jun 05, 2022 4:05 am

Image Two Black Holes Dancing in 3C 75

Explanation: What's happening at the center of active galaxy 3C 75? The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75. Surrounded by multimillion degree x-ray emitting gas, and blasting out jets of relativistic particles the supermassive black holes are separated by 25,000 light-years. At the cores of two merging galaxies in the Abell 400 galaxy cluster they are some 300 million light-years away. Astronomers conclude that these two supermassive black holes are bound together by gravity in a binary system in part because the jets' consistent swept back appearance is most likely due to their common motion as they speed through the hot cluster gas at about 1200 kilometers per second. Such spectacular cosmic mergers are thought to be common in crowded galaxy cluster environments in the distant universe. In their final stages, the mergers are expected to be intense sources of gravitational waves.

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by AVAO » Sun Jun 05, 2022 7:36 am

APOD Robot wrote: Sun Jun 05, 2022 4:05 am Explanation: What's happening at the center of active galaxy 3C 75?..
I think this is wrong. 3C 75 is not a description for a galaxy...

Wikipedia quote:
..3C 75 is a binary black hole system .. in the dumbbell shaped galaxy NGC 1128...
https://en.wikipedia.org/wiki/3C_75

I think the description in wikipedia is also very imprecise.3C 75 denotes the source of two radiojet-emitting sources, for which black holes are assumed to be at the center with a high degree of probability. I also don't think you should consider these two very close galaxies as a single galaxy.
APOD Robot wrote: Sun Jun 05, 2022 4:05 am Astronomers conclude[/url] that these two supermassive black holes are bound together by gravity in a binary system in part because the jets' consistent swept back appearance is most likely due to their common motion as they speed through the hot cluster gas at about 1200 kilometers per second.
I'm not sure if the assumption "two supermassive black holes are bound together by gravity in a binary system" can be correct, because otherwise it would be expected that the two double tails of the black holes moving in the same direction would have to twist helically against each other... which is obviously not the case.

Sorry. Maybe only 50% right. The right arms are intertwined.
But this is hard to explain, if they move in a 90 degree other direction...
Image
https://live.staticflickr.com/65535/521 ... b155_k.jpg
composit-image: Jac Berne (flickr)

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by VictorBorun » Sun Jun 05, 2022 1:35 pm

AVAO wrote: Sun Jun 05, 2022 7:36 am I'm not sure if the assumption "two supermassive black holes are bound together by gravity in a binary system" can be correct
Image
https://live.staticflickr.com/65535/521 ... b155_k.jpg
composit-image: Jac Berne (flickr)
How large share in gravity can possibly have the two BHs if they are 25 000 ly apart and possibly inside the cores of 2 galaxies?
The mass to hold 1200 km/s orbits may be distributed among a trillion stars there

Update. Sorry, I was wrong. The speed of 1200 km/s is through the cluster plasma, causing the jets to be swept back.
The orbital speed must be larger by far

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by MarkBour » Sun Jun 05, 2022 6:34 pm

AVAO wrote: Sun Jun 05, 2022 7:36 am . . .
I'm not sure if the assumption "two supermassive black holes are bound together by gravity in a binary system" can be correct, because otherwise it would be expected that the two double tails of the black holes moving in the same direction would have to twist helically against each other... which is obviously not the case.
@AVAO: Thanks for the helpful notes and comments. However, I don't follow your claim that the jets must intertwine for the BHs to be gravitationally bound.
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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by AVAO » Sun Jun 05, 2022 7:17 pm

MarkBour wrote: Sun Jun 05, 2022 6:34 pm
AVAO wrote: Sun Jun 05, 2022 7:36 am . . .
I'm not sure if the assumption "two supermassive black holes are bound together by gravity in a binary system" can be correct, because otherwise it would be expected that the two double tails of the black holes moving in the same direction would have to twist helically against each other... which is obviously not the case.
@AVAO: Thanks for the helpful notes and comments. However, I don't follow your claim that the jets must intertwine for the BHs to be gravitationally bound.
Maybe you are right. My consideration was that at least in the case of the tails, a tendency should be visible, which indicates mutual encircling circular movements. In other wavelengths, the tails are significantly larger than shown in the APOD. But also there no counter-rotating circular movement is visible.
Image
https://live.staticflickr.com/65535/521 ... b155_k.jpg
Jac Berne (flickr)


I had the example of our solar system in mind. But this example may not apply to the case of 3C 75.

Image
Solar system “vortex” gif (by DjSadhu)

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by Ann » Mon Jun 06, 2022 3:17 am

AVAO wrote: Sun Jun 05, 2022 7:17 pm
MarkBour wrote: Sun Jun 05, 2022 6:34 pm
AVAO wrote: Sun Jun 05, 2022 7:36 am . . .
I'm not sure if the assumption "two supermassive black holes are bound together by gravity in a binary system" can be correct, because otherwise it would be expected that the two double tails of the black holes moving in the same direction would have to twist helically against each other... which is obviously not the case.
@AVAO: Thanks for the helpful notes and comments. However, I don't follow your claim that the jets must intertwine for the BHs to be gravitationally bound.
Maybe you are right. My consideration was that at least in the case of the tails, a tendency should be visible, which indicates mutual encircling circular movements. In other wavelengths, the tails are significantly larger than shown in the APOD. But also there no counter-rotating circular movement is visible.
Image
https://live.staticflickr.com/65535/521 ... b155_k.jpg
Jac Berne (flickr)


I had the example of our solar system in mind. But this example may not apply to the case of 3C 75.

Image
Solar system “vortex” gif (by DjSadhu)
Love that GIF, AVAO! I knew of the helical motion of the planets in the solar system as the Sun drags them along, of course, but the GIF looks stunning, anyway.

But surely there is a difference between a system of two black holes orbiting each other and planets orbiting the Sun? Yes, I know that technically the Sun is in orbit too, because it orbits the center of mass of the solar system, but the Sun holds some 99.9% of the solar system's mass, so I guess it barely wobbles. In the case of the two black holes, surely their combined mass must be more equally distributed, and their orbital motion should be different. Shouldn't it?

Maybe possibly maybe the orbit of the black holes could look something like this? Or no?

Click to play embedded YouTube video.

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by AVAO » Mon Jun 06, 2022 4:30 am

Ann wrote: Mon Jun 06, 2022 3:17 am
Love that GIF, AVAO! I knew of the helical motion of the planets in the solar system as the Sun drags them along, of course, but the GIF looks stunning, anyway.

But surely there is a difference between a system of two black holes orbiting each other and planets orbiting the Sun? Yes, I know that technically the Sun is in orbit too, because it orbits the center of mass of the solar system, but the Sun holds some 99.9% of the solar system's mass, so I guess it barely wobbles. In the case of the two black holes, surely their combined mass must be more equally distributed, and their orbital motion should be different. Shouldn't it?

Maybe possibly maybe the orbit of the black holes could look something like this? Or no?
Click to play embedded YouTube video.
Ann
ThanX Ann

I love this kind of animation of our solar system too.
https://www.youtube.com/watch?v=HHuYMhZBwOA&t=5s

Your video is also very helpful. In contrast to the "flying solar system", here the mutual movement speed changes dynamically. I think it would be an exciting research topic to do these motion simulations with black holes, which also take the respective plasma jets into account.

AVAO

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by orin stepanek » Mon Jun 06, 2022 12:58 pm

cover-his-eyes.jpg
Let a guy sleep
perseusChandra.jpg
Cluster waves
3c75_chandraNRAO_960.jpg
I think they are doing the waltz! :mrgreen:
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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by beryllium732 » Wed Jun 08, 2022 8:35 pm

How would it be for anyone living in a solar system system like ours in between these black holes? Would the radition make life impossible? I wonder how it would look like from the night sky.

Is it two black holes spinning around each other in one galaxy called NGC 1128? Or is it two ellipical galaxies which collided prior?

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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by johnnydeep » Wed Jun 08, 2022 8:52 pm

beryllium732 wrote: Wed Jun 08, 2022 8:35 pm How would it be for anyone living in a solar system system like ours in between these black holes? Would the radition make life impossible? I wonder how it would look like from the night sky.

Is it two black holes spinning around each other in one galaxy called NGC 1128? Or is it two ellipical galaxies which collided prior?
Per Wikipedia:
https://en.wikipedia.org/wiki/NGC_1128 wrote:NGC 1128 is a dumbbell galaxy in the Abell 400 galaxy cluster. At the center of the galaxy is 3C 75, a radio source, and contains two orbiting supermassive black holes that may be merging. Computer simulations indicate that these two black holes will gradually spiral in toward each other until they merge. Lewis Swift is credited with the discovery of NGC 1128 in 1886.
How NGC 1128 managed to obtain two black holes is unclear. I would think the most likely explanation is that one of them came from a pervious merger with another galaxy.
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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by Chris Peterson » Wed Jun 08, 2022 9:06 pm

johnnydeep wrote: Wed Jun 08, 2022 8:52 pm
beryllium732 wrote: Wed Jun 08, 2022 8:35 pm How would it be for anyone living in a solar system system like ours in between these black holes? Would the radition make life impossible? I wonder how it would look like from the night sky.

Is it two black holes spinning around each other in one galaxy called NGC 1128? Or is it two ellipical galaxies which collided prior?
Per Wikipedia:
https://en.wikipedia.org/wiki/NGC_1128 wrote:NGC 1128 is a dumbbell galaxy in the Abell 400 galaxy cluster. At the center of the galaxy is 3C 75, a radio source, and contains two orbiting supermassive black holes that may be merging. Computer simulations indicate that these two black holes will gradually spiral in toward each other until they merge. Lewis Swift is credited with the discovery of NGC 1128 in 1886.
How NGC 1128 managed to obtain two black holes is unclear. I would think the most likely explanation is that one of them came from a pervious merger with another galaxy.
I don't think there are any other theories that address SMBH pairs in single galaxies. Just mergers.
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Re: APOD: Two Black Holes Dancing in 3C 75 (2022 Jun 05)

Post by MarkBour » Sun Jun 12, 2022 5:33 pm

AVAO wrote: Sun Jun 05, 2022 7:17 pm
I had the example of our solar system in mind. But this example may not apply to the case of 3C 75.

Image
Solar system “vortex” gif (by DjSadhu)
I see.

This picture would apply to the two black holes themselves. It would also include any other objects, such as stars and such, that were gravitationally bound to them. But now add to your GIF the Voyager probes. They will fly off, of course. While black hole jets are in a league of their own: they do achieve escape velocity, spectacularly:
https://www.nasa.gov/mission_pages/chan ... limit.html
Using NASA’s Chandra X-ray Observatory, astronomers have seen that the famous giant black hole in Messier 87 is propelling particles at speeds greater than 99% of the speed of light.
But your statement is still intriguing. With 2 BHs giving off 4 jets between them, I would not be too surprised to hear a clever mathematical theorem that if the BHs are gravitationally bound, at least two of the jets must intertwine. Just thinking about it offhand, I can't tell whether or not I should believe that. So, I was asking you because it sounded plausible and I thought maybe you knew of such a result.
Mark Goldfain