NGC 891 Edge on Unbarred Galaxy (niteman1946)

NGC 891 Edge on Unbarred Galaxy

NGC 891 (a.k.a. Caldwell 23) is an edge-on unbarred spiral galaxy about 30 million light-years away in the constellation Andromeda. Discovered by William Herschel on October 6 1784, the galaxy is a member of the NGC 1023 group of galaxies in the Local Supercluster.

It is visible in small to moderate size telescopes as a faint elongated smear of light with a dust lane visible in larger apertures.

Due to its attractiveness and scientific interest, NGC 891 was selected to be the first light image of the Large Binocular Telescope in 2005. It was again used as a first light image of the Discovery Channel Telescope with the Large Monolithic Imager in 2012. Supernova SN 1986J was discovered on August 21, 1986 at apparent magnitude 14. (Source Wikipedia)

Note the very small galaxy at the lower left corner.

The image was captured with a Meade 12"LX200, using the Canon XSi mod (at F7.5), and Atik 383L+ mono (at F6.3).

DSLR: A total of 113 subs at ISO1600 and 5 minutes each (9.42 hr) in 2011, on 10/28 (38), 10/29 (34), , and 11/17 (41).

CCD: A total of 70 subs with binning 1x1 and -10C at 10 minutes each (11.67 hr) in 2012, on 11/14 (18), 11/16 (27), and 11/17 (25) .

Processing was done with PixInsight. This is a medium crop, due to differences in FOV between the two cameras -- North is up.

This was the most recent use of the Atik CCD, and I combined the mono CCD image with the color DSLR from the previous year.

The CCD effort started on Nov. 02 while still using the Orion Skyglow filter. However large gradients in the image prompted me to remove the filter (no help). Ultimately water/ice contamination on the imaging chip proved to be the culprit. Atik Tech Support was very helpful in guiding me through refreshing the dessicant and removing the moisture.

Final
Original
B

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