NGC 891
Edge-On Galaxy NGC 891
NGC 891, also called the Silver Sliver Galaxy, is an edge-on spiral galaxy about 30 million light-years away in the direction of the constellation Andromeda. It is perhaps the most famous example of a spiral galaxy disc seen edge-on as if a dinner plate were held so that we see only the edge and not the center or face of the plate. In this view we can clearly see the galaxy’s center bulge of stars and the extensive dust lanes. In contrast to edge-on galaxies, face-on galaxies have their disc or face tilted toward us as can be seen in M51. Statistically, few galaxies are truly edge-on to us as there are randomly, many more other angles of inclination they may have. Interestingly, our view of NGC 891 is very similar to how our own Milky Way galaxy would look edge on. Furthermore, since our Sun is positioned near the plane of the Milky Way and since the center bulge of stars of our Milky Way galaxy is south of the celestial equator (earth’s equater extended outward), some southern astronomers have noted how similar NGC 891 looks to our own galaxy as seen south of the earth’s equator. Also like our own galaxy, NGC 891 may have a central bar shape as can be seen in NGC 7479. However, recent ultra-high-resolution images of the dusty disk show unusual filamentary patterns extending into the halo of the galaxy, away from its galactic disk. Scientists presume that supernova explosions caused this interstellar dust to be thrown out of the galactic disk toward the halo, therefore NGC 891 may be dustier in appearance that the Milky Way would be. NGC 891 was discovered by William Herschel on October 6, 1784 and is a member of the NGC 1023 group of galaxies in our Local Supercluster of which the Milky Way and surrounding galaxies are members. The image below was taken with an older, smaller CCD camera using the original image processing techniques I developed earlier. The stats for NGC 891 are RA: 02h 22m 33.4s, Dec: +42° 21' 03", Mag: 10.8, Size: 14.3'x2.4', Class: SA(s)b.
Optics: RC Optical System 20" F/8.2 (4165.6 mm Focal Length) Date: July - Oct 2015
Camera: SBIG STXL-11000 with Adaptive Optics Location: Columbus, Texas
Exposure: LRGB = 270:100:60:100 minutes Imager: Kent E. Biggs