APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

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APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by APOD Robot » Fri Aug 06, 2021 4:05 am

Image Stars and Dust Across Corona Australis

Explanation: Cosmic dust clouds cross a rich field of stars in this telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Less than 500 light-years away the dust clouds effectively block light from more distant background stars in the Milky Way. Top to bottom the frame spans about 2 degrees or over 15 light-years at the clouds' estimated distance. At top right is a group of lovely reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. A characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The dust also obscures from view stars in the region still in the process of formation. Just above the bluish reflection nebulae a smaller NGC 6729 surrounds young variable star R Coronae Australis. To its right are telltale reddish arcs and loops identified as Herbig Haro objects associated with energetic newborn stars. Magnificent globular star cluster NGC 6723 is at bottom left in the frame. Though NGC 6723 appears to be part of the group, its ancient stars actually lie nearly 30,000 light-years away, far beyond the young stars of the Corona Australis dust clouds.

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Ann
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by Ann » Fri Aug 06, 2021 4:48 am

NGC6726_6723_2panel1100[1].jpg
Nebulas NGC 6726, 6727, 6729, and IC 4812 up close and personal,
and globular cluster NGC 6723 in the distance. Image: Vikas Chander.
Corona Australis widefield.png
Corona Australis widefield. Unfortunately I saved it on my computer
without crediting the author. Note the little blue "eyes" of the nebulas, and
the long graceful arc of Corona Asutralis stars intersecting
the Corona Australis Molecular Cloud.

Ann
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by VictorBorun » Fri Aug 06, 2021 12:16 pm

Ann wrote:
Fri Aug 06, 2021 4:48 am
Unfortunately I saved it on my computer
without crediting the author.
Ann
FERNANDO MENEZES?

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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by VictorBorun » Fri Aug 06, 2021 12:21 pm

are the Two Eyes in the densest head of a cometary nebula?
If so then where is the supernova or something where the wind that formed this CN originated from ?

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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by VictorBorun » Fri Aug 06, 2021 12:37 pm

I take it the color of the Two Eyes is as follows.

1) There is a little of dust cloud material in front of the stars. The angle of scattering is 10°, the color is slightly warm (pale yellow).

2) There is much light from the dust besides the stars. The angle of scattering is 90°, the color is slightly cool (pale cyan).

3) There is a dense column of dust stretching away behind the close pair of stars making the left eye (see the fragment). The angle of scattering is 170°, the color is very cool (dark blue).
NGC 6727.jpg
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johnnydeep
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by johnnydeep » Fri Aug 06, 2021 3:22 pm

APOD Robot wrote:
Fri Aug 06, 2021 4:05 am
Image Stars and Dust Across Corona Australis

Explanation: Cosmic dust clouds cross a rich field of stars in this telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Less than 500 light-years away the dust clouds effectively block light from more distant background stars in the Milky Way. Top to bottom the frame spans about 2 degrees or over 15 light-years at the clouds' estimated distance. At top right is a group of lovely reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. A characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The dust also obscures from view stars in the region still in the process of formation. Just above the bluish reflection nebulae a smaller NGC 6729 surrounds young variable star R Coronae Australis. To its right are telltale reddish arcs and loops identified as Herbig Haro objects associated with energetic newborn stars. Magnificent globular star cluster NGC 6723 is at bottom left in the frame. Though NGC 6723 appears to be part of the group, its ancient stars actually lie nearly 30,000 light-years away, far
I had a hell of a time trying to map this APOD image to the At top right is a group image until I realized that it had to be vertically reflected and not just rotated a bit. My mental spatial manipulation facility has really declined over the years.

NGC 6723 and Nearby Nebulae.JPG
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by VictorBorun » Fri Aug 06, 2021 4:10 pm

johnnydeep wrote:
Fri Aug 06, 2021 3:22 pm
I had a hell of a time trying to map this APOD image to the At top right is a group image until I realized that it had to be vertically reflected and not just rotated a bit. My mental spatial manipulation facility has really declined over the years.
The same flip is needed to match FERNANDO MENEZES's wide image.
I had to imagine the huge distant globular stellar cluster NGC 6723 as a nose tip for the pair of the blue eyes (and the main cometary nebula body as a long furry body), and then the things clicked

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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by johnnydeep » Fri Aug 06, 2021 4:22 pm

VictorBorun wrote:
Fri Aug 06, 2021 4:10 pm
johnnydeep wrote:
Fri Aug 06, 2021 3:22 pm
I had a hell of a time trying to map this APOD image to the At top right is a group image until I realized that it had to be vertically reflected and not just rotated a bit. My mental spatial manipulation facility has really declined over the years.
The same flip is needed to match FERNANDO MENEZES's wide image.
I had to imagine the huge distant globular stellar cluster NGC 6723 as a nose tip for the pair of the blue eyes (and the main cometary nebula body as a long furry body), and then the things clicked
Thanks. Yup, that works!
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"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."

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Ann
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by Ann » Fri Aug 06, 2021 5:10 pm

VictorBorun wrote:
Fri Aug 06, 2021 12:16 pm
Ann wrote:
Fri Aug 06, 2021 4:48 am
Unfortunately I saved it on my computer
without crediting the author.
Ann
FERNANDO MENEZES?
That's him! Thanks a million!

Ann
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Ann
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by Ann » Fri Aug 06, 2021 5:21 pm

VictorBorun wrote:
Fri Aug 06, 2021 12:21 pm
are the Two Eyes in the densest head of a cometary nebula?
If so then where is the supernova or something where the wind that formed this CN originated from ?
Blue eyes of Corona Australis.png
NGC6726_6723_2panel1100[1].jpg

Check out the blue eyes of Corona Australis (at right), the same blue eyes as you can see in the APOD.

There is no supernova remnant in Corona Australis.

Ann
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by orin stepanek » Fri Aug 06, 2021 6:14 pm

NGC6726_6723_2panel1100.jpg
This is beautiful!

I won't be here/ but if man ever gets past the antiquated
space age and starts exploring the heavens in Ernest!
They will find that we haven't even scratched the surface
of all the wonders out there! (Spoken like a true dreamer.) :lol2:
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Orin

Smile today; tomorrow's another day!

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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by neufer » Fri Aug 06, 2021 6:45 pm

Ann wrote:
Fri Aug 06, 2021 5:21 pm

There is no supernova remnant in Corona Australis.
There probably are supernova remnants in Corona Australis...
we just (JWST?) don't yet have the telescopes to detect them through all that dust.
APOD Robot wrote:
Fri Aug 06, 2021 4:05 am
Image Stars and Dust Across Corona Australis

Explanation: Cosmic dust clouds cross a rich field of stars in this telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Less than 500 light-years away the dust clouds effectively block light from more distant background stars in the Milky Way.
https://en.wikipedia.org/wiki/G350.1-0.3 wrote:
<<G350.1-0.3 is a supernova remnant (formerly mistakenly classified as a distant galaxy) which is located in the constellation Scorpius. It is possibly associated with a neutron star (XMMU J172054.5-372652) formed in the same supernova explosion. The object was formerly mistakenly classified as a distant galaxy. G350.1-0.3 is eight light years across and about 900–1000 years old, making one of the youngest and brightest supernova remnants in the Milky Way. It is unlikely that humans would have seen the supernova explosion because intervening interstellar dust would have likely prevented its viewing from Earth.

G350.1-0.3, a bright radio source in the inner Milky Way, was initially identified by comparing observations from the Molonglo Observatory Synthesis Telescope and Parkes Observatory and classified as a supernova remnant in publications from 1973 and 1975. However, later higher-resolution images in the mid-80s revealed an unexpected irregular morphology that differed substantially from other supernova remnant sources. It was then argued that G350.1-0.3 was a radio galaxy or a galaxy cluster, resulting in a reclassification in which supernova remnant catalogues downgraded the object to "supernova remnant candidate" or dropped it completely; G350.1-0.3 was subsequently "forgotten".

Research published in 2008 combined archival data and new images from XMM-Newton, the European Space Agency's orbiting x-ray telescope, to demonstrate that G350.1-0.3 is a supernova remnant.[3][2] The researchers determined that the object's odd shape resulted from exploding next to a dense gas cloud, approximately 15,000 light years from Earth, that prevented even expansion and produced its elongated shape. The researchers also determined that the nearby thermal X-ray source, XMMU J172054.5-372652, is a central compact object of the supernova.>>
Art Neuendorffer

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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by neufer » Fri Aug 06, 2021 6:52 pm

Click to play embedded YouTube video.
orin stepanek wrote:
Fri Aug 06, 2021 6:14 pm

I won't be here/ but if man ever gets past the antiquated
space age and starts exploring the heavens in Ernest!

They will find that we haven't even scratched the surface
of all the wonders out there! (Spoken like a true dreamer.) :lol2:
Art Neuendorffer

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orin stepanek
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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by orin stepanek » Fri Aug 06, 2021 7:36 pm

neufer wrote:
Fri Aug 06, 2021 6:52 pm
Click to play embedded YouTube video.
orin stepanek wrote:
Fri Aug 06, 2021 6:14 pm

I won't be here/ but if man ever gets past the antiquated
space age and starts exploring the heavens in Ernest!

They will find that we haven't even scratched the surface
of all the wonders out there! (Spoken like a true dreamer.) :lol2:
Hey Neuf; I must be nuts, I watched the whole video! 😂 🤣
I enjoyed! Where do you find this stuff?
Orin

Smile today; tomorrow's another day!

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Re: APOD: Stars and Dust Across Corona Australis (2021 Aug 06)

Post by neufer » Fri Aug 06, 2021 7:59 pm

orin stepanek wrote:
Fri Aug 06, 2021 7:36 pm

Hey Neuf; I must be nuts, I watched the whole video! 😂 🤣
I enjoyed! Where do you find this stuff?
I just search the Worrell Wide Web. KnowhutImean?

Note:
https://en.wikipedia.org/wiki/Centrifugal_force wrote:
<<If Bill "Bobby" Byrge is whirled round on a string, in a horizontal plane, the only real force acting on Bill Byrge in the horizontal plane is applied by the string (gravity acts vertically). There is a net force on Bill Byrge in the horizontal plane which acts toward the center. In an inertial frame of reference, were it not for this net force acting on Bill Byrge, Bill Byrge would travel in a straight line, according to Newton's first law of motion. In order to keep Bill Byrge moving in a circular path, a centripetal force, in this case provided by the string, must be continuously applied to Bill Byrge. As soon as it is removed (for example if the string breaks) Bill Byrge moves in a straight line. In this inertial frame, the concept of centrifugal force is not required as all motion can be properly described using only real forces and Newton's laws of motion. In a frame of reference rotating with Bill Byrge around the same axis as Bill Byrge, Bill Byrge is stationary. However, the force applied by the string is still acting on Bill Byrge. If one were to apply Newton's laws in their usual (inertial frame) form, one would conclude that Bill Byrge should accelerate in the direction of the net applied force—towards the axis of rotation—which he does not do. The centrifugal force and other fictitious forces must be included along with the real forces in order to apply Newton's laws of motion in the rotating frame.>>
Art Neuendorffer