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.
NGC 891, is a typical
spiral galaxy, but is so famous due to its exact edge-on
orientation toward our own galaxy. Images of our own Milky Way
galaxy, taken with normal camera lenses look very similar to
this galaxy, and that is becuase we are in one of the dust lanes
of our galaxy looking out. So if you really want to know what
NGC 891 looks like very close up, merely go into the country to
a darks sight and observe the milky way. Astronomy is a photon
limited science and even if we were very close to the brightest
objects in our sky, most would still look extremely faint and
obscure. 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? sp.