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APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Fri Nov 19, 2021 5:06 am
by APOD Robot
Image NGC 281: Starless with Stars

Explanation: In visible light the stars have been removed from this narrow-band image of NGC 281, a star forming region some 10,000 light-years away toward the constellation Cassiopeia. Stars were digitally added back to the resulting starless image though. But instead of using visible light image data, the stars were added with X-ray data (in purple) from the Chandra X-ray Observatory and infrared data (in red) from the Spitzer Space Telescope. The merged multiwavelength view reveals a multitude of stars in the region's embedded star cluster IC 1590. The young stars are normally hidden in visible light images by the natal cloud's gas and obscuring dust. Also known to backyard astro-imagers as the Pacman Nebula for its overall appearance in visible light, NGC 281 is about 80 light-years across.

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Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Fri Nov 19, 2021 6:42 am
by Ann
starless_color_1024[1].jpg
NGC 281: Starless with Stars.
Image Credit & Copyright: Wido Oerlemans - X-ray: Chandra, Infrared: Spitzer

These are two very different portraits of NGC 281 that make use of Chandra's X-ray detecting ability to figure out what is going on!

The picture at left makes it look as if the central star of NGC 281, O6-type star HD 5005, is emitting a long X-ray jet in one direction. But I can find nothing in the (Wikipedia) caption that supports this, so it might be that we are seeing, edge on, a long dust lane with star formation progressing along the length of it.

Young stars, even low-mass ones, often emit X-rays during parts of their formation, which is to say that some of the stars we can see in the APOD may not be fully formed and "born" yet. Today's APOD shows us what looks like a quite rich cluster of newborn stars, but in visible light, the majority of these stars appear to be mostly invisible.

Ann

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Fri Nov 19, 2021 12:59 pm
by orin stepanek
starless_color_1024.jpg
Ye old Pacman Nebula! :D Did anyone else make the mistake of
pressing the insert coin button? :mrgreen:

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Fri Nov 19, 2021 3:04 pm
by TheZuke!
As opposed to Pacman, today's APOD to me looks more like a creature from the depths of an ocean!
(or a Parana!)

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Fri Nov 19, 2021 5:07 pm
by VictorBorun
Ann wrote: Fri Nov 19, 2021 6:42 am
These are two very different portraits of NGC 281 that make use of Chandra's X-ray detecting ability to figure out what is going on!

Ann
My try to fit the two images. I shifted the hues by +30° to make blue (for X-rays) purple
NGC 281 new.png
X-ray: Chandra, Infrared: Spitzer
NGC 281..png
NGC 281 in the optical (orange, lime) and X-rays (purple)

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Fri Nov 19, 2021 9:29 pm
by johnnydeep
Ann wrote: Fri Nov 19, 2021 6:42 am

These are two very different portraits of NGC 281 that make use of Chandra's X-ray detecting ability to figure out what is going on!

The picture at left makes it look as if the central star of NGC 281, O6-type star HD 5005, is emitting a long X-ray jet in one direction. But I can find nothing in the (Wikipedia) caption that supports this, so it might be that we are seeing, edge on, a long dust lane with star formation progressing along the length of it.

Young stars, even low-mass ones, often emit X-rays during parts of their formation, which is to say that some of the stars we can see in the APOD may not be fully formed and "born" yet. Today's APOD shows us what looks like a quite rich cluster of newborn stars, but in visible light, the majority of these stars appear to be mostly invisible.

Ann
The "edge on aspect" of NGC 281? It looks more face on than edge on to me.

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Sat Nov 20, 2021 6:15 am
by Ann
johnnydeep wrote: Fri Nov 19, 2021 9:29 pm
Ann wrote: Fri Nov 19, 2021 6:42 am

These are two very different portraits of NGC 281 that make use of Chandra's X-ray detecting ability to figure out what is going on!

The picture at left makes it look as if the central star of NGC 281, O6-type star HD 5005, is emitting a long X-ray jet in one direction. But I can find nothing in the (Wikipedia) caption that supports this, so it might be that we are seeing, edge on, a long dust lane with star formation progressing along the length of it.

Young stars, even low-mass ones, often emit X-rays during parts of their formation, which is to say that some of the stars we can see in the APOD may not be fully formed and "born" yet. Today's APOD shows us what looks like a quite rich cluster of newborn stars, but in visible light, the majority of these stars appear to be mostly invisible.

Ann
The "edge on aspect" of NGC 281? It looks more face on than edge on to me.
Well, sue me! :wink: I just quoted Wikipedia!

For myself, I'd say it looks like the massive central star is ejecting a long X-ray jet in one direction. The only other explanation I can think of is that there might be a hidden dust lane (behind the massive foreground dust lane) where new stars form, so that we indeed have an edge-on view (in X-rays) of a "long drawn-out" site of star formation in NGC 281. See my illustration below.

Possible hidden dust lane in NGC 281.png

Is there a hidden starforming dust lane where I drew that brown line?

Ann

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Sat Nov 20, 2021 1:53 pm
by neufer
Click to play embedded YouTube video.

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Sat Nov 20, 2021 4:03 pm
by johnnydeep
Ann wrote: Sat Nov 20, 2021 6:15 am
johnnydeep wrote: Fri Nov 19, 2021 9:29 pm
Ann wrote: Fri Nov 19, 2021 6:42 am

These are two very different portraits of NGC 281 that make use of Chandra's X-ray detecting ability to figure out what is going on!

The picture at left makes it look as if the central star of NGC 281, O6-type star HD 5005, is emitting a long X-ray jet in one direction. But I can find nothing in the (Wikipedia) caption that supports this, so it might be that we are seeing, edge on, a long dust lane with star formation progressing along the length of it.

Young stars, even low-mass ones, often emit X-rays during parts of their formation, which is to say that some of the stars we can see in the APOD may not be fully formed and "born" yet. Today's APOD shows us what looks like a quite rich cluster of newborn stars, but in visible light, the majority of these stars appear to be mostly invisible.

Ann
The "edge on aspect" of NGC 281? It looks more face on than edge on to me.
Well, sue me! :wink: I just quoted Wikipedia!

For myself, I'd say it looks like the massive central star is ejecting a long X-ray jet in one direction. The only other explanation I can think of is that there might be a hidden dust lane (behind the massive foreground dust lane) where new stars form, so that we indeed have an edge-on view (in X-rays) of a "long drawn-out" site of star formation in NGC 281. See my illustration below.

Possible hidden dust lane in NGC 281.png

Is there a hidden starforming dust lane where I drew that brown line?

Ann
Hard to know. But I will say now that the bumpy diagonal from upper left to lower right does look like an edge of some planar surface or other:

Edge-On View of a Planar surface?
Edge-On View of a Planar surface?

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Sat Nov 20, 2021 5:49 pm
by neufer
johnnydeep wrote: Sat Nov 20, 2021 4:03 pm
Ann wrote: Sat Nov 20, 2021 6:15 am
Is there a hidden starforming dust lane where I drew that brown line?
Hard to know.

But I will say now that the bumpy diagonal from upper left to lower right does look like an edge of some planar surface or other.
https://www.etymonline.com/search?q=corrugate wrote:
<<corrugate (v.): "to wrinkle, to draw or contract into folds," 1610s, from Latin corrugatus, past participle of corrugare "to make full of wrinkles, wrinkle very much" (also "produce loathing, cause disgust"), from assimilated form of com-, here perhaps an intensive prefix (see com-), + rugare "to wrinkle," from ruga "crease, groove," which is of uncertain origin (see rugae).
...........................................................................
rugae (n.) 1775, in zoology, anatomy, etc., "a fold or wrinkle," plural of ruga (1775), from Latin ruga "a wrinkle in the face," from Proto-Italic *rouga-, which is of uncertain origin. "Since words for 'wrinkle' and 'crease' are often derived from 'to be rugged', from which also 'to belch' is often derived ..., the most obvious connection is with e-rugere 'to belch'".>>
https://en.wikipedia.org/wiki/Pizza_box wrote:
<<The first patent for a pizza box (or pizza Pac-kage) made of corrugated cardboard was applied in 1963 and it already displayed the characteristics of today's pizza packaging: plane blanks, foldability without need of adhesive, stackability and ventilation slots. The combination of such slots along with water vapour absorbing materials (absorption agent) prevented the humidity build-ups that characterized traditional transport packaging. It is assumed that the pizza box was invented by Domino's Pizza, even if they did not file a patent application. Until 1988, this chain employed a type of packaging whose front side was not directly connected to the lateral sides, but rather the flaps fixed to the lateral sides were folded inward under the lid. This design is also known as "Chicago folding". Domino's was the first pizza producer which employed pizza boxes on a large scale and in this way expanded its delivery range beyond the area immediately close to the pizzeria.>>
https://en.wikipedia.org/wiki/Pac-Man wrote:
<<The inspiration for the Pac-Man character was the image of a pizza with a slice removed. The original Japanese title of Puck Man was changed to Pac-Man for international releases as a preventative measure against defacement of the arcade machines by changing the P to an F.>>
https://en.wikipedia.org/wiki/Corrugated_fiberboard wrote:
<<Corrugated paper was patented in England in 1856, and used as a liner for tall hats, but corrugated boxboard was not patented and used as a shipping material until 20 December 1871. The patent was issued to Albert Jones of New York City for single-sided corrugated board. Jones used the corrugated board for wrapping bottles and glass lantern chimneys. The first machine for producing large quantities of corrugated board was built in 1874 by G. Smyth, and in the same year Oliver Long improved upon Jones' design by inventing corrugated board with liner sheets on both sides, thereby inventing corrugated board as it came to be known in modern times. Scottish-born Robert Gair invented the pre-cut paperboard box in 1890 – flat pieces manufactured in bulk that folded into boxes. Gair's invention resulted from an accident. He was a Brooklyn printer and paper-bag maker during the 1870s. While he was printing seed bags, a metal ruler used to crease bags shifted in position and cut them. Gair discovered that by cutting and creasing in one operation he could make prefabricated paperboard boxes. Applying this idea to corrugated boxboard was a straightforward development when the material became available in the early 20th century.>>

Re: APOD: NGC 281: Starless with Stars (2021 Nov 19)

Posted: Sat Nov 20, 2021 7:32 pm
by johnnydeep
neufer wrote: Sat Nov 20, 2021 5:49 pm
johnnydeep wrote: Sat Nov 20, 2021 4:03 pm
Ann wrote: Sat Nov 20, 2021 6:15 am
Is there a hidden starforming dust lane where I drew that brown line?
Hard to know.

But I will say now that the bumpy diagonal from upper left to lower right does look like an edge of some planar surface or other.
https://www.etymonline.com/search?q=corrugate wrote:
<<corrugate (v.): "to wrinkle, to draw or contract into folds," 1610s, from Latin corrugatus, past participle of corrugare "to make full of wrinkles, wrinkle very much" (also "produce loathing, cause disgust"), from assimilated form of com-, here perhaps an intensive prefix (see com-), + rugare "to wrinkle," from ruga "crease, groove," which is of uncertain origin (see rugae).
...........................................................................
rugae (n.) 1775, in zoology, anatomy, etc., "a fold or wrinkle," plural of ruga (1775), from Latin ruga "a wrinkle in the face," from Proto-Italic *rouga-, which is of uncertain origin. "Since words for 'wrinkle' and 'crease' are often derived from 'to be rugged', from which also 'to belch' is often derived ..., the most obvious connection is with e-rugere 'to belch'".>>
https://en.wikipedia.org/wiki/Pizza_box wrote:
<<The first patent for a pizza box (or pizza Pac-kage) made of corrugated cardboard was applied in 1963 and it already displayed the characteristics of today's pizza packaging: plane blanks, foldability without need of adhesive, stackability and ventilation slots. The combination of such slots along with water vapour absorbing materials (absorption agent) prevented the humidity build-ups that characterized traditional transport packaging. It is assumed that the pizza box was invented by Domino's Pizza, even if they did not file a patent application. Until 1988, this chain employed a type of packaging whose front side was not directly connected to the lateral sides, but rather the flaps fixed to the lateral sides were folded inward under the lid. This design is also known as "Chicago folding". Domino's was the first pizza producer which employed pizza boxes on a large scale and in this way expanded its delivery range beyond the area immediately close to the pizzeria.>>
https://en.wikipedia.org/wiki/Pac-Man wrote:
<<The inspiration for the Pac-Man character was the image of a pizza with a slice removed. The original Japanese title of Puck Man was changed to Pac-Man for international releases as a preventative measure against defacement of the arcade machines by changing the P to an F.>>
https://en.wikipedia.org/wiki/Corrugated_fiberboard wrote:
<<Corrugated paper was patented in England in 1856, and used as a liner for tall hats, but corrugated boxboard was not patented and used as a shipping material until 20 December 1871. The patent was issued to Albert Jones of New York City for single-sided corrugated board. Jones used the corrugated board for wrapping bottles and glass lantern chimneys. The first machine for producing large quantities of corrugated board was built in 1874 by G. Smyth, and in the same year Oliver Long improved upon Jones' design by inventing corrugated board with liner sheets on both sides, thereby inventing corrugated board as it came to be known in modern times. Scottish-born Robert Gair invented the pre-cut paperboard box in 1890 – flat pieces manufactured in bulk that folded into boxes. Gair's invention resulted from an accident. He was a Brooklyn printer and paper-bag maker during the 1870s. While he was printing seed bags, a metal ruler used to crease bags shifted in position and cut them. Gair discovered that by cutting and creasing in one operation he could make prefabricated paperboard boxes. Applying this idea to corrugated boxboard was a straightforward development when the material became available in the early 20th century.>>
A pleasing web of seeming interconnectedness.