Comments and questions about the
APOD on the main view screen.
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XgeoX
- Science Officer
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- AKA: Uncle Rico
Post
by XgeoX » Tue Feb 22, 2022 11:12 am
My favorite quasar image…
![Image](https://external-preview.redd.it/gGEmZqTZKP4J55BXpj4jYFadgxEIsw32ZLd4UwsywDY.jpg?auto=webp&s=5e5999252ac5eee42c9df3c40ca47cc2533d7cdd)
“This NASA/ESA Hubble Space Telescope picture may trick you into thinking that the galaxy in it — known as UZC J224030.2+032131 — has not one but five different nuclei. In fact, the core of the galaxy is only the faint and diffuse object seen at the centre of the cross-like structure formed by the other four dots, which are images of a distant quasar located in the background of the galaxy.
The picture shows a famous cosmic mirage known as the Einstein Cross, and is a direct visual confirmation of the theory of general relativity. It is one of the best examples of the phenomenon of gravitational lensing — the bending of light by gravity as predicted by Einstein in the early 20th century. In this case, the galaxy’s powerful gravity acts as a lens that bends and amplifies the light from the quasar behind it, producing four images of the distant object.
The quasar is seen as it was around 11 billion light-years ago, in the direction of the constellation of Pegasus, while the galaxy that works as a lens is some ten times closer. The alignment between the two objects is remarkable (within 0.05 arcseconds), which is in part why such a special type of gravitational lensing is observed.
This image is likely the sharpest image of the Einstein Cross ever made, and was produced by Hubble’s Wide Field and Planetary Camera 2, and has a field of view of 26 by 26 arcseconds.
Credit:
ESA/Hubble & NASA“
Eric
Ego vigilate
Ego audire
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MarkE
Post
by MarkE » Tue Feb 22, 2022 12:38 pm
This illustration looks very similar to something i came across on the original GalazyZoo citizen science project around 14 years ago; i named it 'Oliver' in a comment i posted....should be still in their archived forum.
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orin stepanek
- Plutopian
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by orin stepanek » Tue Feb 22, 2022 12:38 pm
APOD Quasars are among the most distant objects we see
Thank God for that! They look pretty scary!
![Laughing :lol2:](./images/smilies/asterisk_laugh.gif)
Kinda pretty though!
Don't look at me; I didn't make this mess! I'm just enjoying it!
Orin
Smile today; tomorrow's another day!
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Ranzilch
- Asternaut
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- Joined: Tue Feb 22, 2022 1:04 pm
Post
by Ranzilch » Tue Feb 22, 2022 1:26 pm
The word “intervening universe” here is the same meaning of "intervening galaxy" or it's the late period of universe from a timeline perspective?
Anyone please explain me more information about this term "intervening universe", I am a bit confused here, thanks.
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Chris Peterson
- Abominable Snowman
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by Chris Peterson » Tue Feb 22, 2022 3:02 pm
Ranzilch wrote: ↑Tue Feb 22, 2022 1:26 pm
The word “intervening universe” here is the same meaning of "intervening galaxy" or it's the late period of universe from a timeline perspective?
Anyone please explain me more information about this term "intervening universe", I am a bit confused here, thanks.
I take it to be a reference to time. Observations that span the very early Universe to the present.
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neufer
- Vacationer at Tralfamadore
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by neufer » Tue Feb 22, 2022 4:15 pm
Chris Peterson wrote: ↑Tue Feb 22, 2022 3:02 pm
Ranzilch wrote: ↑Tue Feb 22, 2022 1:26 pm
The word “intervening universe” here is the same meaning of "intervening galaxy" or it's the late period of universe from a timeline perspective? Anyone please explain me more information about this term "intervening universe", I am a bit confused here, thanks.
I take it to be a reference to time. Observations that span the very early Universe to the present.
- Clearly, these early quasars are suffering from compulsive and other eating disorders:
https://en.wikipedia.org/wiki/Intervention_(counseling) wrote:
<<An intervention is an orchestrated attempt by one or more [universes] – usually family and friends – to get someone to seek professional help with a substance use disorder or some kind of traumatic event or crisis, or other serious problem. Interventions have been used to address serious personal problems, including alcohol use disorder, compulsive gambling, substance use disorder, compulsive eating and other eating disorders, self harm and being the victim of abuse.>>
- A tutor who tooted the flute,
Tried to tutor two tooters to toot.
Said the two to the tutor,
"Is it tougher to toot
Or to tutor two tooters to toot?"
Art Neuendorffer
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Fred the Cat
- Theoretic Apothekitty
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- AKA: Ron
- Location: Eagle, Idaho
Post
by Fred the Cat » Tue Feb 22, 2022 5:19 pm
Webb in 3D to shine
light in 3D but it's like waiting for astronomical Christmas.
![Sad :(](./images/smilies/icon_sad.gif)
Freddy's Felicity "Only ascertain as a cat box survivor"
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johnnydeep
- Commodore
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- Joined: Sun Feb 20, 2011 8:57 pm
Post
by johnnydeep » Tue Feb 22, 2022 10:27 pm
From the Wikipedia link to quasar:
https://en.wikipedia.org/wiki/Quasar wrote:A quasar (/ˈkweɪzɑːr/; also known as a quasi-stellar object, abbreviated QSO) is an extremely luminous active galactic nucleus (AGN), powered by a supermassive black hole, with mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc.
Gas in the disc falling towards the black hole heats up because of friction and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosities thousands of times greater than a galaxy such as the Milky Way.[2][3] Usually, quasars are categorized as a subclass of the more general category of AGN. The redshifts of quasars are of cosmological origin.[4]
I am always amazed that the quasar's infalling gas and dust can generate so much energy merely due to
friction - with no nuclear processes involved - and nevertheless outshine an entire galaxy of furiously fusing stars!
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
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Chris Peterson
- Abominable Snowman
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Post
by Chris Peterson » Tue Feb 22, 2022 10:54 pm
johnnydeep wrote: ↑Tue Feb 22, 2022 10:27 pm
From the Wikipedia link to quasar:
https://en.wikipedia.org/wiki/Quasar wrote:A quasar (/ˈkweɪzɑːr/; also known as a quasi-stellar object, abbreviated QSO) is an extremely luminous active galactic nucleus (AGN), powered by a supermassive black hole, with mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc.
Gas in the disc falling towards the black hole heats up because of friction and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosities thousands of times greater than a galaxy such as the Milky Way.[2][3] Usually, quasars are categorized as a subclass of the more general category of AGN. The redshifts of quasars are of cosmological origin.[4]
I am always amazed that the quasar's infalling gas and dust can generate so much energy merely due to
friction - with no nuclear processes involved - and nevertheless outshine an entire galaxy of furiously fusing stars!
It isn't really friction in the usual sense of the word. It's a fluid dynamic process where atoms collide with each other and transfer momentum in complex ways. The physics is related to ideas like viscosity and moment diffusion. You have a very large volume of gas that is compressed to something more like a liquid than a gas (near the event horizon) moving at relativistic speeds. That's an immense amount of kinetic energy.
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Ranzilch
- Asternaut
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- Joined: Tue Feb 22, 2022 1:04 pm
Post
by Ranzilch » Wed Feb 23, 2022 1:18 pm
neufer wrote: ↑Tue Feb 22, 2022 4:15 pm
Chris Peterson wrote: ↑Tue Feb 22, 2022 3:02 pm
Ranzilch wrote: ↑Tue Feb 22, 2022 1:26 pm
The word “intervening universe” here is the same meaning of "intervening galaxy" or it's the late period of universe from a timeline perspective? Anyone please explain me more information about this term "intervening universe", I am a bit confused here, thanks.
I take it to be a reference to time. Observations that span the very early Universe to the present.
- Clearly, these early quasars are suffering from compulsive and other eating disorders:
https://en.wikipedia.org/wiki/Intervention_(counseling) wrote:
<<An intervention is an orchestrated attempt by one or more [universes] – usually family and friends – to get someone to seek professional help with a substance use disorder or some kind of traumatic event or crisis, or other serious problem. Interventions have been used to address serious personal problems, including alcohol use disorder, compulsive gambling, substance use disorder, compulsive eating and other eating disorders, self harm and being the victim of abuse.>>
- A tutor who tooted the flute,
Tried to tutor two tooters to toot.
Said the two to the tutor,
"Is it tougher to toot
Or to tutor two tooters to toot?"
I think I get it.
Thank you, both.
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johnnydeep
- Commodore
- Posts: 3101
- Joined: Sun Feb 20, 2011 8:57 pm
Post
by johnnydeep » Wed Feb 23, 2022 1:22 pm
Chris Peterson wrote: ↑Tue Feb 22, 2022 10:54 pm
johnnydeep wrote: ↑Tue Feb 22, 2022 10:27 pm
From the Wikipedia link to quasar:
https://en.wikipedia.org/wiki/Quasar wrote:A quasar (/ˈkweɪzɑːr/; also known as a quasi-stellar object, abbreviated QSO) is an extremely luminous active galactic nucleus (AGN), powered by a supermassive black hole, with mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc.
Gas in the disc falling towards the black hole heats up because of friction and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosities thousands of times greater than a galaxy such as the Milky Way.[2][3] Usually, quasars are categorized as a subclass of the more general category of AGN. The redshifts of quasars are of cosmological origin.[4]
I am always amazed that the quasar's infalling gas and dust can generate so much energy merely due to
friction - with no nuclear processes involved - and nevertheless outshine an entire galaxy of furiously fusing stars!
It isn't really friction in the usual sense of the word. It's a fluid dynamic process where atoms collide with each other and transfer momentum in complex ways. The physics is related to ideas like viscosity and moment diffusion. You have a very large volume of gas that is compressed to something more like a liquid than a gas (near the event horizon) moving at relativistic speeds. That's an immense amount of kinetic energy.
Interesting. Still seems hard to believe that the energy released can beat fusion. I wonder what percent of the infalling matter's mass gets converted to energy in the accretion disk. Or is that not happening at all and all the energy ultimately coming from the change in gravitational potential energy? (Hmm, I seem to remember being confused about this in prior posts about things falling onto neutron stars...)
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
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alter-ego
- Serendipitous Sleuthhound
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Post
by alter-ego » Thu Feb 24, 2022 5:10 am
For all practical purposes, consider 50% of the mass energy is converted in the accretion disk, compared to about 0.5% in fusion. It's hard to fathom, and kind of ironic that the weak force is the primary channel for the highest emitted powers in the Universe.
A pessimist is nothing more than an experienced optimist
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johnnydeep
- Commodore
- Posts: 3101
- Joined: Sun Feb 20, 2011 8:57 pm
Post
by johnnydeep » Thu Feb 24, 2022 1:20 pm
alter-ego wrote: ↑Thu Feb 24, 2022 5:10 am
For all practical purposes, consider 50% of the mass energy is converted in the accretion disk, compared to about 0.5% in fusion. It's hard to fathom, and kind of ironic that the
weak force is the primary channel for the highest emitted powers in the Universe.
I assume you meant the "weakest force", not "weak force", right? Meaning gravity is the weakest of the four forces, not that the nuclear weak force is involved.
And wow. So is the mass coming from the matter in the accretion disk, or from the black hole, or from gravity itself, or some combination?
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
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Chris Peterson
- Abominable Snowman
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by Chris Peterson » Thu Feb 24, 2022 3:42 pm
johnnydeep wrote: ↑Wed Feb 23, 2022 1:22 pm
Chris Peterson wrote: ↑Tue Feb 22, 2022 10:54 pm
johnnydeep wrote: ↑Tue Feb 22, 2022 10:27 pm
From the Wikipedia link to quasar:
I am always amazed that the quasar's infalling gas and dust can generate so much energy merely due to
friction - with no nuclear processes involved - and nevertheless outshine an entire galaxy of furiously fusing stars!
It isn't really friction in the usual sense of the word. It's a fluid dynamic process where atoms collide with each other and transfer momentum in complex ways. The physics is related to ideas like viscosity and moment diffusion. You have a very large volume of gas that is compressed to something more like a liquid than a gas (near the event horizon) moving at relativistic speeds. That's an immense amount of kinetic energy.
Interesting. Still seems hard to believe that the energy released can beat fusion. I wonder what percent of the infalling matter's mass gets converted to energy in the accretion disk. Or is that not happening at all and all the energy ultimately coming from the change in gravitational potential energy? (Hmm, I seem to remember being confused about this in prior posts about things falling onto neutron stars...)
What does that mean, "beat fusion"? If all the matter in the accretion disc underwent fusion, it would be vastly more energetic. As it is, something like a third of the mass in the disc is eventually converted to energy, which is a huge amount of energy. In a star, you have only the tiniest amount of material that is undergoing fusion. When hydrogen fuses to helium, the energy conversion is very efficient. But it is also very rare. If all the material in a star fused simultaneously, you would also have an intensity greater than a galaxy. In fact, that's pretty much what happens in a supernova.
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neufer
- Vacationer at Tralfamadore
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Post
by neufer » Thu Feb 24, 2022 5:26 pm
Chris Peterson wrote: ↑Thu Feb 24, 2022 3:42 pm
johnnydeep wrote: ↑Wed Feb 23, 2022 1:22 pm
Still seems hard to believe that the energy released can beat fusion. I wonder what percent of the infalling matter's mass gets converted to energy in the accretion disk. Or is that not happening at all and all the energy ultimately coming from the change in gravitational potential energy? (Hmm, I seem to remember being confused about this in prior posts about things falling onto neutron stars...)
What does that mean, "beat fusion"? If all the matter in the accretion disc underwent fusion, it would be vastly more energetic. As it is, something like a third of the mass in the disc is eventually converted to energy, which is a huge amount of energy. In a star, you have only the tiniest amount of material that is undergoing fusion. When hydrogen fuses to helium, the energy conversion is very efficient. But it is also very rare. If all the material in a star fused simultaneously, you would also have an intensity greater than a galaxy. In fact, that's pretty much what happens in a supernova.
Fusion is basically a process by which:
- 56 protons of mass 56.4075 Daltons are transformed into one
iron-56 nuclei of mass 55.935 Daltons for an efficiency of ~ 1%
This does not come close to efficiency of a quasar
https://en.wikipedia.org/wiki/Foe_(unit) wrote:
<<A foe is a unit of energy equal to 10
44 joules or 10
51 ergs, used to express the large amount of energy released by a supernova. This unit of measure is convenient because a supernova typically releases about one foe of
observable energy in a very short period (which can be measured in seconds).
[Note: a core collapse supernova can release ~100 foe of neutrinos.] In comparison, if the Sun had its current luminosity throughout its entire lifetime, it would release ≈ 1.2 foe. One solar mass has a rest mass energy of 1787 foe.>>
https://en.wikipedia.org/wiki/Quasar wrote:
<<Since quasars exhibit all the properties common to other active galaxies such as Seyfert galaxies, the emission from quasars can be readily compared to those of smaller active galaxies powered by smaller supermassive black holes. To create a luminosity of 10
40 watts (the typical brightness of a quasar), a supermassive black hole would have to consume the material equivalent of 10 solar masses per year.
The brightest known quasars devour 1000 solar masses of material every year. The largest known is estimated to consume matter equivalent to 10 Earths per second. Quasar luminosities can vary considerably over time, depending on their surroundings.
Radiation from quasars is partially "nonthermal" (i.e., not due to black-body radiation), and approximately 10% are observed to also have jets and lobes like those of radio galaxies that also carry significant (but poorly understood) amounts of energy in the form of particles moving at relativistic speeds. Quasars can be detected over the entire observable electromagnetic spectrum, including radio, infrared, visible light, ultraviolet, X-ray and even gamma rays. Most quasars are brightest in their rest-frame ultraviolet wavelength of 121.6 nm Lyman-alpha emission line of hydrogen, but due to the tremendous redshifts of these sources, that peak luminosity has been observed as far to the red as 900.0 nm, in the near infrared. A minority of quasars show strong radio emission, which is generated by jets of matter moving close to the speed of light. When viewed downward, these appear as blazars.>>
Art Neuendorffer
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Chris Peterson
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by Chris Peterson » Thu Feb 24, 2022 6:28 pm
neufer wrote: ↑Thu Feb 24, 2022 5:26 pm
Chris Peterson wrote: ↑Thu Feb 24, 2022 3:42 pm
johnnydeep wrote: ↑Wed Feb 23, 2022 1:22 pm
Still seems hard to believe that the energy released can beat fusion. I wonder what percent of the infalling matter's mass gets converted to energy in the accretion disk. Or is that not happening at all and all the energy ultimately coming from the change in gravitational potential energy? (Hmm, I seem to remember being confused about this in prior posts about things falling onto neutron stars...)
What does that mean, "beat fusion"? If all the matter in the accretion disc underwent fusion, it would be vastly more energetic. As it is, something like a third of the mass in the disc is eventually converted to energy, which is a huge amount of energy. In a star, you have only the tiniest amount of material that is undergoing fusion. When hydrogen fuses to helium, the energy conversion is very efficient. But it is also very rare. If all the material in a star fused simultaneously, you would also have an intensity greater than a galaxy. In fact, that's pretty much what happens in a supernova.
Fusion is basically a process by which:
- 56 protons of mass 56.4075 Daltons are transformed into one
iron-56 nuclei of mass 55.935 Daltons for an efficiency of ~ 1%
This does not come close to efficiency of a quasar :!:
Define efficiency as you are using it. I'd call that 100% efficiency, less whatever is lost to heat in (inelastic) collisions that don't result in fusion.