Celestial hemisphere:  Northern  ·  Constellation: Ursa Major (UMa)  ·  Contains:  NGC 2841
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NGC2841 Spiral Galaxy, niteman1946
NGC2841 Spiral Galaxy
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NGC2841 Spiral Galaxy

Getting plate-solving status, please wait...
NGC2841 Spiral Galaxy, niteman1946
NGC2841 Spiral Galaxy
Powered byPixInsight

NGC2841 Spiral Galaxy

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Description

NGC 2841 is an unbarred spiral galaxy in the northern constellation of Ursa Major, discovered on 9 March 1788 by German-born astronomer William Herschel. 
J.L.E. Dreyer, the author of the New General Catalogue, described it as, "very bright, large, very much extended 151°, very suddenly much brighter middle equal to 10th magnitude star".
Initially thought to be about 30 million light-years distant, a 2001 Hubble Space Telescope survey of the galaxy's Cepheid variables determined its distance to be approximately 46 million light-years.
This is the prototype for the flocculent spiral galaxy, a type of spiral galaxy whose arms are patchy and discontinuous but very tightly-wound.
The galaxy has no central bar.  It is inclined by an angle of 68° to the line of sight from the Earth, with the major axis aligned along a position angle of 148°.
The properties of NGC 2841 are similar to those of the Andromeda Galaxy. It is home to a large population of young blue stars, and a few H II regions. The luminosity of the galaxy is 2E10 L☉ and it has a combined mass of 7E10 M☉. Its disk of stars can be traced out to a radius of around 228 kly (70 kpc). This disk begins to warp at a radius of around 98 kly, suggesting the perturbing effect of in-falling matter from the surrounding medium.
The rotational behavior of the galaxy suggests there is a massive nuclear bulge at the core. A prominent molecular ring is orbiting at a radius of 7–20 kly, which is providing a star-forming region of gas and dust. The nucleus appears decoupled and there is a counter-rotating element of stars and gas in the outer parts of the nucleus, suggesting a recent interaction with a smaller galaxy.Four supernovae have been observed in the galaxy.
[Source:  Wikipedia, with edits]

Capture Information:
The image was captured with the iOptron CEM120 mount, the venerable Meade 12"LX200 SCT OTA, and my QHYCCD QHY294m Pro mono CMOS camera at F7.16 (2182mm FL). 
Astronomik's Luminance, Red, Green and Blue broad band filters were used.

Image Information -- 2023
LUM :  37 subs (3.08hr) on Apr 21st and 27th.
RED :  10 subs (0.83hr) on Apr 21st.
GRN :  10 subs (0.83hr) on Apr 21st and 27th.
BLU :   10 subs (0.83hr) on Apr 27th.

All exposures were at 5 minutes (300s) each, 1600 gain, 56 offset, 1x1 bin and -10C.

Processing was done with PixInsight, following (for the most part) kayronjm's tutorial of Feb. 24th from several years back.
Luminance was generated using only subs from the LUM filter.  R, G and B were collected for the color mix.

North is to the right (pretty sure), and this is a medium crop due to the FOV’s “width” being slightly greater than the filter’s reach. 

Comments:
This appears to be the 1st time I’ve run at this target.  
It came out OK, but I was late starting the image, and just able to squeeze it in between rain, clouds and trees.
I noticed an image of the galaxy posted on the Italian Astronomy web site (forum.astrofili.org) only a few weeks back.  It was done by an accomplished astro photographer Roberto Marinoni and published by NASA on their March 23rd APOD (Astronomy Picture of the Day) web site.
While my image is very inferior when compared to Roberto’s, I do wish I had started sooner and gathered more photons. 

ONE LAST THING:
Nothing new from iOptron regarding the mount’s unacceptable RA excursion issue.  
However, my mounts tracking did much better on this target.  
There are so many things that affect the tracking so I’m not getting too excited about the mount healing itself.

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NGC2841 Spiral Galaxy, niteman1946