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NGC 891 (1,656 of 18,816)

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Silver Sliver Galaxy

NGC 891, LEDA 9031, MCG+07-05-046, UGC 1831, Caldwell 23, Silver Sliver Galaxy, V 19, h 218, GC 527

RA: 02h 22m 32.9s
Dec: +42° 20′ 45.8″

Con: Andromeda
Ch: MSA:101, U2:62, SA:4

Ref: SIMBAD

(reference key)

Type: galaxy, Sb

Mag: B=10.8, V=?

Size: 12.3′ x 3.09′
PA: 22°

Historical observations

Caroline Herschel (1783)

Discovered by Caroline Herschel and reported in William Herschel's "Catalogue of One Thousand new Nebulae and Clusters of Stars" (1786) in which he noted that she used "an excellent small Newtonian Sweeper of 27 inches focal length, and a power of 30.".

See also NGC 253 and NGC 2204.

William Herschel

Catalogue of One Thousand new Nebulae and Clusters of Stars

Synonyms: H V-019

Recorded by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "cB, mE, above 15' long, 3' broad, a black division 3' or 4' long in the middle."

Ref: [1786RSPT...76..457H]

John Herschel (1833)

Observations of Nebulae and Clusters of Stars, made at Slough, with a Twenty-Feet Reflector, between the years 1825 and 1833

"Fig. 28. V.19 - An extraordinary object. Perhaps the representation in the figure is too nicely symmetrical, as it certainly is too sharply defined and distinct. It is of the last degree of faintness, and may very well be unperceived, though full in the field of view. There can hardly be a doubt of its being a thin flat ring, of enormous dimensions, seen very obliquely."

Ref: [1833PTRS..123..359H] p.498

Birr Castle/Lord Rosse

An observer using the 72-inch f/8.8 speculum telescope at Birr Castle, sketched this galaxy, showing its black division. It was measured as extending 10' 29 arcseconds in PA 23 degrees.

NGC/IC Dreyer (1888, 1895, 1908)

This 10.8 mag. galaxy is described in the NGC as "remarkable, bright, very large, very much elongated in PA 22."

Published comments

Burnham's Celestial Handbook

One of the most striking examples of an edge-on spiral galaxy, "equalling in interest the more famous NGC 4565 in Coma Berenices." He notes that the galaxy is not an easy object for small telescopes, "since the surface brightness is quite low," but on a clear night it may be detected with a 6-inch.

Burnham's Celestial Handbook

Burnham notes that photographs of the galaxy reveal "a complex system of dark clouds extending across the entire length of the galaxy", which was known to Lord Rosse, as is shown in sketches he made in 1850 with a 6-foot reflector in Ireland.

Sandage & Tammann (1975)

Sandage, A. & Tammann, G. A. (1975) Steps toward the Hubble constant. V - The Hubble constant from nearby galaxies and the regularity of the local velocity field. ApJ, 196, 313-328. [1975ApJ...196..313S]

(1975, Astrophysical Journal, 196, 313-328) includes this galaxy in the NGC 1023 Group. Members include NGC 891, NGC 925, NGC 1003, NGC 1023, NGC 1058 & IC 239.

de Vaucouleurs, G. (1975)

de Vaucouleurs, G. (1975) Nearby groups of galaxies. In: Kuiper, G. (ed) Stars and Stellar Systems. Volume 9: Galaxies and the Universe. Chapter 14, p557.

5. The nearer groups within 10 megaparsecs

G7. NGC 1023 Group.

Brightest members: 1023, 925, 891, IC 239, 1058, 1003

Several large spirals of type Sc and later including NGC 925, NGC 1003, NGC 1058 and IC 239 are clustered around the bright lenticular system NGC 1023 in low galactic latitudes at the border of Perseus and Andromeda. The edge-on Sb system NGC 891 and the close pair of late-type spirals NGC 672, IC 1727 are probable or possible outlying members. NGC 1156, a Magellanic irregular some 20 away, is another possible outlying member. The group is at the edge of the galactic absorption belt (which may conceal some members in lower latitudes) .. Several dwarf irregulars are probable members .. the overall dimensions of the group 20x10 (including NGC 672) are rather large, but the diameter of the core around NGC 1023 is only 8. two of the brightest supernovae appears in NGC 1003 and NGC 1058.

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 11.5 mag galaxy. Their coded description reads EON,B,BM,EQDKLN.

Sandage, A. (1961) The Hubble Atlas of Galaxies

This galaxy appears on page 25 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Clark, R.N. (1990)

See also "Visual Astronomy of the Deep Sky" by Roger N. Clark (1990, Sky Publishing Corporation) page 83.

Photo index

by Jim Lucyk: Observer's Guide (Astro Cards) 9-10/88 p33, Sky&Tel. 1/75 p58, Sky&Tel. 2/81 p100, Sky&Tel. 6/75 p403, Sky&Tel. 12/88 p713, Sky&Tel. 8/76 p104, Sky&Tel. 8/86 p113, Burnhams V1 p155, Astronomy mag. 7/77 p54, Hubble Atl.of Gal. (Sandage 1961) p25, Field Guide to Stars & Planets (Menzel, 1964) p133.

Modern observations

Ancient City Astron.Club (1980)

described as "extremely elongated, edge-on, bright nucleus fading outwards. 6-inch, 48x."

Hartung, E.J. (1968) Astron.Obj.South.Tel

Notes that "at low altitude, I see only a faint spindle 7' x 1' with no apparent nucleus, in a field well sprinkled with stars."

Walter Scott Houston

writes: "I estimate its brightness as magnitude 9.5. With an 8-inch telescope in the Empire Mountains of Arizona, this slender, 12' long galaxy reminded me of famous NGC 4564 in Coma Berenices. With averted vision I could see a dark lane running the entire length of NGC 891, and distinct scallops could be seen along the band's edge. After continued observation, it was possible to hold the dark lane with direct vision. The excellent optics of my 4-inch Clark refractor have only once shown the dark band, and never the scallops. Although the galaxy is easily found in my 5-inch apogee scope at 20x, there is not even a hint of the obscuring material."

Sanford (1989) Observing the Constellations

Notes that in an 8-inch telescope it is seen as a large 12' streak of light with a dark lane particularly prominent in larger telescopes. It is not bright (12th magnitude) and needs a Moonless night and pure skies to be seen well. Its catalogued dimensions are 14' by 2'.

Raasch, Rick (1993)

writes in "The Focal Point", Volume 6, No. 2 (1993) "NGC 891 In photographs, one of the finest objects to be seen. A classic example of an edge-on spiral galaxy. Visually, it is large and faint, almost like the ghost of the galaxy shown in textbooks. It is 15' X 3', oriented N-S, with faint dust lanes along its eastern side and through the center. Time is needed to extract detail in this beautiful object."

Tom Lorenzin

Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "11.5M; 12'x 1' extent; edge-on spiral with equatorial dust lane; good supernova prospect 20' NW of bright star (6.7M) SAO 38002; photo at HAG-25."

Ware, Donald J

:"This is a large galaxy, 12-15'x3', extended NNE-SSW. Using averted vision, one can see a dust lane bisecting it at its center. Although it is large, it appears rather faint, so time is needed to extract detail in this beautiful object."

[amastro] Deep observing NGC 891

Sometimes its amazing how large aperture can perform under a good, dark sky. Even now, after +25 years observing experience I can be 'wowed' if the conditions are right.

This past Friday, I had a chance to observe the well-known galaxy NGC 891 under fairly high magnification (305x) using a 24-inch Tectron. I was playing a 'hunch' - that the dark absorption structures sometimes known as galactic chimneys may be visible.( For those interested, these structures are discussed in Howe and Savage, 1997AJ 114, 6)

I was not disappointed..

I was treated to a dust band showing far more detail than most images (including CCD) reveal, especially north and south of the main hub of the galaxy. The "edges" of the main dust band was for the lack of a better erm - "furry" , as if some of the larger extraplanar structures were beginning to be resolved by the scope. The most remarkable detail was visible in the area south of the hub, as the band broke up into a complex interfingering of bright knots and dark rifts.

I had mentioned this may make an interesting target for giant scopes and CCD's in my next Sky N' Tel article but it looks like this needs to be revised :-)

Hopefully, I'll hear from others observing the dust structures in NGC 891.

- Rich

[amastro] NGC 891 - a correction and a challenge

First, a correction to my observation of NGC 891:

]beginning to be resolved by the scope. The most remarkable detail was

]visible in the area south of the hub, as the band broke up into a complex

]interfingering of bright knots and dark rifts.

The _northern_ end, not the southern is the visually more complex although both portions reveal a truly fascinating interplay of dust and nebulousity. Second, who has seen the tiny galaxy (the brightest of a distant group) off the NE side of the northern extension?

Using FitsView, the coordinates of the object are:

RA 02 22 42

Dec +42 22 40.1

PA ~ 30 degrees

Mag (v) ~ 17 to 17.5 (this is very rough..)

If its already plotted on the latest versions of MegaStar, my apologies to Larry (I have a fairly old version of the software).

- Rich

Brian Skiff

Brian Skiff:

POSS: m12.5 * 4'.1 along maj axis; m14 * 5'.6 along maj axis, just E of SSW tip. m11.5 * (L&deV: V=11.98/0.41) 1'.55 along maj axis, 0'.45 off it. m14.5 * 2'.9 radius from nuc in dk lane. these imply 15cm sizes: 11'.2x0'.9 halo and 2'.5x0'.9 core. closer * of pair in 15cm & 30cm obs may be V=13.43/0.68 * in L&deV.

6cm - not really.

7cm - pretty f @ 30x but recog by spindle shape. 50x shows m11.5 * on W flank of core. difficult to est size due to fntness. tough object. BS, 26Nov1992, Anderson Mesa.

8cm - 20x: pretty f short streak elong N-S. BS, 13Aug1983, Anderson Mesa.

15cm - vlg, velong gx, mob br but fairly losfcbr. dk lane evident @ 80x/140x as it crosses core at least. vwk vbroad concen in disk, core is just wk broad. on SSW (gx in pa20) the halo reaches past m12.5 * to m14.5 * that lies on E side of tip. NNE end not as br---harder to define end although seems about as long. brtr m11.5 * NW of center is just beyond core. m13.5-14 pair off SSE side of core resolved. m14-14.5 * two-thirds way from center to m12.5 * on maj axis SSW, looks like knot in gx. 12'x2'. BS, 29Sep1989, Anderson Mesa.

- in passing @ 80x: the dk lane is confidently vis intermittently with just-right averted vis. BS, 27Nov1992, Anderson Mesa.

25cm - 10'x1' w/many close *s. broad and mod brtr cen region. impressively f.

30cm - just vis as 7'x2' blotch of vlosfcbr (at threshold). brtst area is just S of m13 *. five *s inv. elong in pa35. CBL.

- vthin in pa30. vlittle concen. broad core 4'x2'. 10'x2'.5 overall. m12 * N of core; two m14.5 *s, 30" sep in pa0, lie S of core. gx extends all the way to m13 * SSW. before reaching this *, however, there is a 1'.5 diam br patch. the core seems to have two condens, at 220x, w/the brtr one to the E side. nice. halo more extensive SSW. CBL.

amastro [MAC 022+4222]

Subject: [amastro] Einstein's Cross & MAC 022+4222

] Another object I'd like to try is the galaxy almost in contact with

] N891 in Pegasus, MAC 0222+4222 (02h 22m 41.7" +42 22 31). As many

] times as I've looked at N891 I've never even thought to look for it.

] Has anyone seen it visually, and if so what size aperture, and what

] power? Will I see it with a 25" under 6.1 magnitude skies?

]

] Thanks.

]

] Kent Blackwell

-----------------------------------------

MAC 022+4222 apparently is a real faint and tiny object. If it was more removed from such a show object as N891 perhaps more people would have seen it. Until MegaStar I simply never knew it existed. This might be reserved for those with 36"ers.

Has anyone seen it?

--------------------------------------

In the 1988/89 time frame I did look for this a couple of times with the 31-inch at Warren Rupp, but never did see it. I was using a picture out of Burnhams for a guide (which is where I first noticed it). But I was never able to use very high (<320x) power due to the seeing condidtions.

Bob Bunge

--------------------------------------

Just for grins, Einstein's Cross is also often refered to as Huchra's Lens, after John P. Huchra. He discovered this particular quasar/galaxy relationship on a spectrum of the lensing galaxy's nucleus using the MMT in September of 1984.

Jay McNeil

--------------------------------------

] Has anyone seen it?

Yes, Jose Sancho spent a great deal of time at the Ultimate Star Party, altitude about 6500' near McDonald Observatory in West Texas on 891 and the MAC galaxies around it. I don't recall the limiting magnitude that night, but I do remember seeing the gegenshein. This was in late October or early November 2 years ago, He was using a 18" f/4.5 and logged this one as well. He showed it to me and Larry Mitchell. Jose used Real Sky with the MegaStar Overlay for field identification, and confirmation. If I recall correctly he logged six that night near 891. I don't recall the magnification he used, but it was fairly high. He uses a tracking platform with his telescope as do I to reach very high power. I remember it being faint in his 18", and Larry and I congratulating him on tackling it and the other MACs in the area.

Barbara Wilson.

Contemporary observations

Magda Streicher

(no date)

Alldays (22.50S, 20.12E, 770m).

12-inch f/10 SCT (95x)

Soft elongated galaxy, which brighten slowly to a very bright nucleus. Very elongated. Faint star on the north edge of the soft spindle.

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