by Ann » Sat Nov 27, 2021 8:19 am
Well, there is nothing for it: Today's APOD doesn't speak strongly to me, because of the "flat" colors. I so much prefer the overall color profile of Robert Gendler's image.
Yes, but... When you look at a larger version of today's APOD and start getting into details...!!!
Have you ever seen such a lovely 3-armed background galaxy?
Some notable objects in the upper right part of the APOD.
Let's look at the annotations of the picture at right:
L = Low surface brightness galaxy
1A = Lenticular (barred) galaxy with a large yellow halo
2A = Elliptical galaxy with a large yellow halo
3A = Barred red-and-dead galaxy with a yellow tidal tail
4A = Edge-on spiral galaxy with a yellow bulge and a (rather extensive) blue disk
5A = Starforming disk galaxy, probably interacting with galaxy 4A.
Do 4A and 5A belong to the same group of galaxies as 1A, 2A and 3A (which certainly belong together themselves)? They might, but I doubt it.
6 = Clump of stars belonging to M101. Note the presence of both blue and red stars here.
7 = Very bright red supergiant star in M101 or very redshifted background galaxy? I guess it is a galaxy.
8 = A rather small region of intense star formation in M101. The turquoise color probably means we are looking at a nebula (or nebulas). The arc-shaped formation is either an arc-shaped nebula (as in the California nebula) or an arc of stars arching over a dense core of stars.
9 = A group of very faint, differently colored (including very red) background galaxies. There appears to be at least one red M101 star here too.
10 = Two red background galaxies.
11 = A globular cluster? If so, it must be very compact.
Galaxy NGC 6946 by Hubble. Note the small bright white clump of stars surrounded by a "cloud" or an halo of stars at upper right. I think that #8 in my annotated image might possibly be a young version of this.
Ann
[float=right][img3="M101. Credit: Credit: Hubble Legacy Archive, ESA, NASA; Processing and additional imaging - Robert Gendler"]http://apod.nasa.gov/apod/image/1104/M101HST-Gendler900.jpg[/img3][/float][img3="M101. Image Credit: NASA, ESA, CFHT, NOAO; Acknowledgement - K.Kuntz (GSFC), F.Bresolin (U.Hawaii), J.Trauger (JPL), J.Mould (NOAO), Y.-H.Chu (U. Illinois)"]https://apod.nasa.gov/apod/image/2111/M101_hst1280.jpg[/img3]
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Well, there is nothing for it: Today's APOD doesn't speak strongly to me, because of the "flat" colors. I so much prefer the overall color profile of Robert Gendler's image.
Yes, but... When you look at a larger version of today's APOD and start getting into details...!!!
[float=left][attachment=1]3 armed background galaxy in M101 APOD November 27 2021.png[/attachment][c][size=85][color=#0040FF]Have you ever seen such a lovely 3-armed background galaxy?[/color][/size][/c][/float] [float=right][attachment=0]M101 closeup and background galaxies APOD November 27 2021 annotated.png[/attachment][c][size=75][color=#0040FF]Some notable objects in the upper right part of the APOD.[/color][/size][/c][/float]
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Let's look at the annotations of the picture at right:
L = Low surface brightness galaxy
1A = Lenticular (barred) galaxy with a large yellow halo
2A = Elliptical galaxy with a large yellow halo
3A = Barred red-and-dead galaxy with a yellow tidal tail
4A = Edge-on spiral galaxy with a yellow bulge and a (rather extensive) blue disk
5A = Starforming disk galaxy, probably interacting with galaxy 4A.
[size=85][color=#0040FF]Do 4A and 5A belong to the same group of galaxies as 1A, 2A and 3A (which certainly belong together themselves)? They might, but I doubt it.[/color][/size]
6 = Clump of stars belonging to M101. Note the presence of both blue and red stars here.
7 = Very bright red supergiant star in M101 or very redshifted background galaxy? I guess it is a galaxy.
8 = A rather small region of intense star formation in M101. The turquoise color probably means we are looking at a nebula (or nebulas). The arc-shaped formation is either an arc-shaped nebula (as in the California nebula) or an arc of stars arching over a dense core of stars.
9 = A group of very faint, differently colored (including very red) background galaxies. There appears to be at least one red M101 star here too.
10 = Two red background galaxies.
11 = A globular cluster? If so, it must be very compact.
[img3="NGC 6946. Image credit: ESA/Hubble & NASA, A. Leroy, K.S. Long"]https://www.nasa.gov/sites/default/files/styles/full_width_feature/public/thumbnails/image/potw2101a.jpg[/img3]
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Galaxy NGC 6946 by Hubble. Note the small bright white clump of stars surrounded by a "cloud" or an halo of stars at upper right. I think that #8 in my annotated image might possibly be a young version of this.
Ann