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APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 5:06 am
by APOD Robot
NGC 1365: Majestic Island Universe
Explanation: Barred spiral galaxy NGC 1365 is truly a majestic
island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the faint but heated constellation
Fornax, NGC 1365 is a
dominant member of the well-studied
Fornax Cluster of galaxies. This impressively
sharp color image shows the intense, reddish star forming regions near the ends of central bar and along the spiral arms, with details of the obscuring dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think
NGC 1365's prominent bar plays a crucial role in the
galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the
central black hole.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 7:37 am
by AVAO
APOD Robot wrote: ↑Thu Dec 22, 2022 5:06 am
At the core lies a supermassive black hole. Astronomers think
NGC 1365's prominent bar plays a crucial role in the
galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the
central black hole.
The central bar fans out into different armlike "feathers". Does the statement above mean that the dust, the gas and the stars forming in it flow from all these "feathers" to the central bar and from there are drawn into the black hole in the center, where they are "devoured" by it?
biggg:https://live.staticflickr.com/65535/525 ... 59bf_o.jpg
biggg:https://live.staticflickr.com/65535/525 ... 3c4e_o.jpg
Source: Based on pictures from Judy Schmidt (HST & JWST)
https://www.flickr.com/photos/geckzilla/52289366115
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 1:28 pm
by Ann
Fantastic images, AVAO, HST, JWST and Geck!
You asked:
The central bar fans out into different armlike "feathers". Does the statement above mean that the dust, the gas and the stars forming in it flow from all these "feathers" to the central bar and from there are drawn into the black hole in the center, where they are "devoured" by it?
Well, given that NGC 1365 has a modest AGN, an Active Galactic Nucleus, gas is definitely being devoured, albeit at a slow pace, by the black hole of this galaxy.
Take a look at the HST/JWST/Geck picture of NGC 1365 that you posted yourself, and look at all the "white blobs" near the core of the galaxy. These things are almost certainly huge young star clusters, and they have formed because so much gas has been flowing into this region, most likely along the dust lanes of the bar.
Some gas must also be devoured by the black hole, causing the accretion disk to act up. It is after all the the accretion disks, not the black holes themselves, that launch jets. Note in the HST/JWST/Geck picture of NGC 1365 at least one long straight jet, which however doesn't seem to be centered on the core of NGC 1365. Several other, shorter or more crooked structures may possibly also be jets.
But while gas is clearly flowing along the dust lanes of the bar into the core region of NGC 1365, gas is also gathering at two other places in NGC 1365, namely, at the two bar ends.
Look at the very pink regions of the arms of NGC 1365. These are actually the regions closest to the bar ends. Gas gathers here and gives rise to enhanced levels of star formation.
Milky Way. Image: Nick Risinger.
We can actually see the bar ends of the Milky Way, too. There are enhanced levels of star formation in Cygnus (where the North America Nebula is located for example) and Carina (which hosts the Carina Nebula).
But Zeta Ophiuchi is a nearby object that has nothing to do with the bar or the bar ends of the Milky Way,
Ann
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 1:53 pm
by johnnydeep
So, in the "
central black hole" link to the infra red image from Judy Schmidt, it is said that there are really two bars - the main one quite prominent in visible light, and the smaller one more prominent in IR. But I'm having trouble seeing it. This is Judy's image:
I
think the yellow line marks the 2nd bar, and though the main bar seems to be not showing at all, having been replaced by ring and arm-like structures, I
think it is along the green line in my marked-up image here:
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 2:50 pm
by VictorBorun
Looking at the APOD (which is in visual wavelength range) I wonder how they are oriented in 3d:
the bar,
the bright ellipsis (is it a disk at an angle?) around the centre point,
the pair of dust lanes marking the flows to (or from?) the centre point (or just the bright ellipsis?)
the arms and the disk at the largest scale
Looking at the IR pic, I don't understand how to fit it to the APOD
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 3:29 pm
by orin stepanek
Majestic is right;
![Cool 8-)](./images/smilies/icon_cool.gif)
a very colorful galaxy with an active Black hole!
Love this Photo!
![💞](//cdn.jsdelivr.net/gh/twitter/twemoji@latest/assets/svg/1f49e.svg)
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 4:54 pm
by AVAO
VictorBorun wrote: ↑Thu Dec 22, 2022 2:50 pm
Looking at the IR pic, I don't understand how to fit it to the APOD
..might be helpful..
https://live.staticflickr.com/65535/522 ... 7bcc_o.jpg
https://live.staticflickr.com/65535/522 ... 37dd_o.jpg
jac berne (flickr)
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 5:24 pm
by DL MARTIN
Thought I read recently that dark energy was tied to photons. If so, and the photons we are seeing have been travelling for 60 million light-years, then does that not explain where dark energy is hiding out?
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 5:28 pm
by Chris Peterson
DL MARTIN wrote: ↑Thu Dec 22, 2022 5:24 pm
Thought I read recently that dark energy was tied to photons. If so, and the photons we are seeing have been travelling for 60 million light-years, then does that not explain where dark energy is hiding out?
I'm not aware of any dark energy theory that involves photons.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 5:37 pm
by Ann
johnnydeep wrote: ↑Thu Dec 22, 2022 1:53 pm
So, in the "
central black hole" link to the infra red image from Judy Schmidt, it is said that there are really two bars - the main one quite prominent in visible light, and the smaller one more prominent in IR. But I'm having trouble seeing it. This is Judy's image:
I
think the yellow line marks the 2nd bar, and though the main bar seems to be not showing at all, having been replaced by ring and arm-like structures, I
think it is along the green line in my marked-up image here:
As to where the two bars of NGC 1365 are, this is my best guess:
NGC 1365 in infrared. Possible bars are marked.
ESO/P. Grosbøl.
Ann
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 6:26 pm
by SeedsofEarfth
The photon=dark energy link may be found in this article:
https://ui.adsabs.harvard.edu/abs/2012A ... ive%20mass.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 6:34 pm
by Chris Peterson
Thanks. But that doesn't link dark energy to any photons known to exist, but to a hypothetical different kind of photon. Basically, they're just suggesting that if there was a type of photon with negative mass, there is a mathematical path to explaining dark energy.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 6:40 pm
by AVAO
Ann wrote: ↑Thu Dec 22, 2022 1:28 pm
...Well, given that NGC 1365 has a modest AGN, an Active Galactic Nucleus, gas is definitely being devoured, albeit at a slow pace, by the black hole of this galaxy.
Take a look at the HST/JWST/Geck picture of NGC 1365 that you posted yourself, and look at all the
"white blobs" near the core of the galaxy. These things are almost certainly huge young star clusters, and they have formed because so much gas has been flowing into this region, most likely along the dust lanes of the bar.
Ann
ThanX Ann - Your comments are always great to read!
... and I think you are right about the star nests - sorry clusters of course - near the core. With the JWST NIRCam you can see them very well
![Image](https://live.staticflickr.com/65535/52580340485_52f052e5e1_o.jpg)
jac berne (flickr)
compare to https://arxiv.org/pdf/0907.2602.pdf page 25
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 8:40 pm
by AVAO
Congratulations to Martin Pugh - Incredibly good galaxy portrait!
...The beauty seems to show a little more blush compared to his APOD 2018
https://apod.nasa.gov/apod/ap181228.html
![Image](https://apod.nasa.gov/apod/image/2212/NGC1365-CDK24-CDK17_1024.jpg)
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 9:57 pm
by OB1Kubota
What I'd like to see is a three dimensional portrait of the galaxy and relative directional motion of it's different areas. The reddish dust lanes, if that's correct, leading toward the center appear to be rising up from the plane and returning toward the center. Just saying it has an appearance of a prominence in that central region. I'm wondering what the gravitational forces are throughout the galaxy.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 10:55 pm
by Fred the Cat
OB1Kubota wrote: ↑Thu Dec 22, 2022 9:57 pm
What I'd like to see is a three dimensional portrait of the galaxy and relative directional motion of it's different areas. The reddish dust lanes, if that's correct, leading toward the center appear to be rising up from the plane and returning toward the center. Just saying it has an appearance of a prominence in that central region. I'm wondering what the gravitational forces are throughout the galaxy.
From the "
Dark Side"
![ninja :ninja:](./images/smilies/ninja.gif)
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Thu Dec 22, 2022 11:16 pm
by David Nance
Amazing and very beautiful image! This image makes the galaxy have the appearance of arms as huge interlinking rings of stars with the left arm overlapping the arm that extends from the right side with a central bar interconnecting them. Is there any radio imaging to determine the shape of any surrounding dust/gas? Perhaps satellite dwarf galaxies?
This image has more of a three dimensional aspect than any previous ones I've seen of NGC 1365.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Fri Dec 23, 2022 12:04 am
by DL MARTIN
Thanks for the clarification on the dark energy/photon thinking.
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Fri Dec 23, 2022 1:37 am
by Ann
David Nance wrote: ↑Thu Dec 22, 2022 11:16 pm
Amazing and very beautiful image! This image makes the galaxy have the appearance of arms as huge interlinking rings of stars with the left arm overlapping the arm that extends from the right side with a central bar interconnecting them. Is there any radio imaging to determine the shape of any surrounding dust/gas? Perhaps satellite dwarf galaxies?
This image has more of a three dimensional aspect than any previous ones I've seen of NGC 1365.
There is a study published
here where NGC 1365 has been observed at many different wavelengths, mostly in submillimeter and radio wavelengths.
As for the overall shape of NGC 1365, check out this image processed by Robert Gendler:
Go to
this page to see larger versions of the image.
I also recommend
this page, where you can see many different pictures of NGC 1365, including the Robert Gendler one. But there are no JWST pictures there.
Ann
Re: APOD: NGC 1365: Majestic Island Universe (2022 Dec 22)
Posted: Fri Dec 23, 2022 3:34 am
by David Nance
Ann, thanks for the response.