Comments and questions about the
APOD on the main view screen.
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Ann
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by Ann » Wed May 17, 2023 3:51 am
VictorBorun wrote: ↑Wed May 17, 2023 12:54 am
Ann wrote: ↑Tue May 16, 2023 6:09 am
Eagle Nebula Jac Berne SPITZER HERSCHEL Mix.png
Eagle Nebula detail annotated Gianni Lacroce.png
So the brightest star forming area, as detected by Spitzer and Herschel, is located just below the "Great Arch of the Eagle"!
So, Chris, you were right: The dark "opening" of the "arch" of the Eagle Nebula is not an opening at all, but a dust cloud. And at one end of this cloud of gas and dust, star formation is taking place.
Ann
I wonder whether it's possible for a star formation to be this IR-bright and compact or is it in fact an accretion disk of a 1000 suns massive black hole?
And if this IR-lamp is also the X-lamp illuminating, exciting and turning to comet-like columns the Pillars of Creation, from «above» ? Hidden in X-range by the Black Black Bok cloud
Black holes are absolutely not my forte, but I find it extremely likely that the most IR-bright region in the Eagle Nebula is not a black hole but a region of ongoing star formation.
Let's compare the Eagle Nebula with NGC 2264, the Christmas Tree Cluster and Cone Nebula region:
NGC 2264 in optical light. Note the two yellowish regions.
Credit: Velimir Popov and Emil Ivanov.
NGC 2264 in infrared. Note the star formation that corresponds to
the yellowish regions in the Popov/Ivanov image.
Credit: NASA/JPL-Caltech/P.S. Teixeira
Ann
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VictorBorun
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by VictorBorun » Wed May 17, 2023 5:46 am
Chris Peterson wrote: ↑Wed May 17, 2023 2:55 am
VictorBorun wrote: ↑Wed May 17, 2023 12:54 am
Ann wrote: ↑Tue May 16, 2023 6:09 am
Eagle Nebula Jac Berne SPITZER HERSCHEL Mix.png
Eagle Nebula detail annotated Gianni Lacroce.png
So the brightest star forming area, as detected by Spitzer and Herschel, is located just below the "Great Arch of the Eagle"!
So, Chris, you were right: The dark "opening" of the "arch" of the Eagle Nebula is not an opening at all, but a dust cloud. And at one end of this cloud of gas and dust, star formation is taking place.
Ann
I wonder whether it's possible for a star formation to be this IR-bright and compact or is it in fact an accretion disk of a 1000 suns massive black hole?
And if this IR-lamp is also the X-lamp illuminating, exciting and turning to comet-like columns the Pillars of Creation, from «above» ? Hidden in X-range by the Black Black Bok cloud
IR bright material is cold. Accretion discs are hot, and emit strongly in UV or even x-rays.
So? Do you say that an accretion disc is nothing like one-temperature thing that's entitled to have some typical thermal energy of a particle or of a radiated photon and therefore to be bright in a narrow range like the visible light range for Sun? And if this lamp is bright both as an ionising UV or X-ray and in IR tells that it's not a one-temperature thermal source?
JWST team
says a galaxy with an active core is IR-bright:
NGC 7319
...
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Chris Peterson
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by Chris Peterson » Wed May 17, 2023 1:04 pm
VictorBorun wrote: ↑Wed May 17, 2023 5:46 am
Chris Peterson wrote: ↑Wed May 17, 2023 2:55 am
VictorBorun wrote: ↑Wed May 17, 2023 12:54 am
I wonder whether it's possible for a star formation to be this IR-bright and compact or is it in fact an accretion disk of a 1000 suns massive black hole?
And if this IR-lamp is also the X-lamp illuminating, exciting and turning to comet-like columns the Pillars of Creation, from «above» ? Hidden in X-range by the Black Black Bok cloud
IR bright material is cold. Accretion discs are hot, and emit strongly in UV or even x-rays.
So? Do you say that an accretion disc is nothing like one-temperature thing that's entitled to have some typical thermal energy of a particle or of a radiated photon and therefore to be bright in a narrow range like the visible light range for Sun? And if this lamp is bright both as an ionising UV or X-ray and in IR tells that it's not a one-temperature thermal source?
JWST team
says a galaxy with an active core is IR-bright:
NGC 7319
What I'm saying is that
material that is radiating strongly in IR is cool, and accretion disks are very hot and will gave very low IR emission compared with shorter wavelengths.
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VictorBorun
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by VictorBorun » Wed May 17, 2023 3:37 pm
Chris Peterson wrote: ↑Wed May 17, 2023 1:04 pm
VictorBorun wrote: ↑Wed May 17, 2023 5:46 am
Chris Peterson wrote: ↑Wed May 17, 2023 2:55 am
IR bright material is cold. Accretion discs are hot, and emit strongly in UV or even x-rays.
So? Do you say that an accretion disc is nothing like one-temperature thing that's entitled to have some typical thermal energy of a particle or of a radiated photon and therefore to be bright in a narrow range like the visible light range for Sun? And if this lamp is bright both as an ionising UV or X-ray and in IR tells that it's not a one-temperature thermal source?
JWST team
says a galaxy with an active core is IR-bright:
NGC 7319
What I'm saying is that
material that is radiating strongly in IR is cool, and accretion disks are very hot and will gave very low IR emission compared with shorter wavelengths.
I thought to emit much energy in low energy photons you need a great mass that makes a large accretion disk with cold but large outskirts
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Chris Peterson
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by Chris Peterson » Wed May 17, 2023 3:47 pm
VictorBorun wrote: ↑Wed May 17, 2023 3:37 pm
Chris Peterson wrote: ↑Wed May 17, 2023 1:04 pm
VictorBorun wrote: ↑Wed May 17, 2023 5:46 am
So? Do you say that an accretion disc is nothing like one-temperature thing that's entitled to have some typical thermal energy of a particle or of a radiated photon and therefore to be bright in a narrow range like the visible light range for Sun? And if this lamp is bright both as an ionising UV or X-ray and in IR tells that it's not a one-temperature thermal source?
JWST team
says a galaxy with an active core is IR-bright:
NGC 7319
What I'm saying is that
material that is radiating strongly in IR is cool, and accretion disks are very hot and will gave very low IR emission compared with shorter wavelengths.
I thought to emit much energy in low energy photons you need a great mass that makes a large accretion disk with cold but large outskirts
That would make sense for a protoplanetary accretion disc. Not, I think, for one around a black hole.
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VictorBorun
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by VictorBorun » Wed May 17, 2023 5:46 pm
Chris Peterson wrote: ↑Wed May 17, 2023 3:47 pm
VictorBorun wrote: ↑Wed May 17, 2023 3:37 pm
Chris Peterson wrote: ↑Wed May 17, 2023 1:04 pm
What I'm saying is that
material that is radiating strongly in IR is cool, and accretion disks are very hot and will gave very low IR emission compared with shorter wavelengths.
I thought to emit much energy in low energy photons you need a great mass that makes a large accretion disk with cold but large outskirts
That would make sense for a protoplanetary accretion disc. Not, I think, for one around a black hole.
Can't we scale up a protoplanetary accretion disc by scaling up the whole mass and the central object mass, one sun star to 10 suns blue giant star to 100 suns supergiant star to 1000 suns direct collapse black hole?
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Chris Peterson
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by Chris Peterson » Wed May 17, 2023 5:58 pm
VictorBorun wrote: ↑Wed May 17, 2023 5:46 pm
Chris Peterson wrote: ↑Wed May 17, 2023 3:47 pm
VictorBorun wrote: ↑Wed May 17, 2023 3:37 pm
I thought to emit much energy in low energy photons you need a great mass that makes a large accretion disk with cold but large outskirts
That would make sense for a protoplanetary accretion disc. Not, I think, for one around a black hole.
Can't we scale up a protoplanetary accretion disc by scaling up the whole mass and the central object mass, one sun star to 10 suns blue giant star to 100 suns supergiant star to 1000 suns direct collapse black hole?
That doesn't sound reasonable to me. Turbulent processes don't scale linearly. I think that the accretion disc around a black hole is a much more compact structure than that around a protostar.