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RA: 12h 18m 57.54s
Dec: +47° 18′ 14.3″
Con: Canes Venatici
Ch: MSA:592, U2:74, SA:7
Type: galaxy (AGN LINER-type), Sbc
Mag: B=9.6, V=?
Size: 16.98′ x 6.456′
Synonyms: H V-043
Recorded on March 9, 1788 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "very brilliant, bright nucleus with faint milky branches np sf 15' long and to the sf running into vF nebulosity extending a great way. The nucleus is not round."
See the entry for NGC 5236 for Sir John Herschel's comments.
A supernova erupted in this galaxy in 1981 (17.0p)
The RNGC (Sulentic and Tifft 1973) notes that this is a 9.5 mag galaxy. Their coded description reads S,LG,B,DKPCHS -CTDSK 2 DIFO ARMS.
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]
Sandage and Tammann (1975, Astrophysical Journal, 196, 313-328) includes this galaxy in the Canes Venatici I Cloud. Members include NGC 4136, NGC 4150, NGC 4214, NGC 4244, NGC 4248, NGC 4258, NGC 4395, NGC 4449, NGC 4736, NGC 4826 & IC 4182.
This galaxy appears on page 33 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).
Doig, P. (1925) Notes on the nebulae and clusters in Webb's 'Celestial Objects for Common Telescopes' (Sixth edition, Vol.ii). Part V. M.N.R.A.S., 36(3), 89.
"nebula, S, B nucleus, not well shown on plate A571 [exposure 21min]."
Bailey, S.I. (1908) A catalogue of bright stars and nebulae. Ann.Harv.Coll.Obs., 60(8), 199.
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
G3. CVn I Cloud.
Brightest members: 4736, 4258, 4826, 4449, 4214.
A loose cloud of low-velocity objects may be isolated in the foreground of several more distant, overlapping groups and clouds in the UMa-CVn-Coma area. This whole region is described as the CVn cluster or M94 group by van den Bergh, who points out that many dwarfs are concentrated in this area; Sersic describes a subset as the UMa I group and another as the UMa II group (both of which, however, are all within the boundaries of CVn). ... After much searching and with some hesitation in borderline cases, the following objects were isolated as members of the foreground CVn I cloud (or restricted M94 group): NGC 4136, 4150, 4214, 4244, 4258, 4395, 4736, IC 4182, A1157 (=DDO 115) and possibly NGC 4826. Other possible dwarf members include DDO 99, 125, 126, 129, 133, 141, 143 and 156. All members are spirals of type Sb or later and Magellanic irregulars.
Burnham calls it a 9th mag spiral galaxy, measuring 19.5' x 6.5', which is remarkable, very bright, very large, very much elongated, suddenly brighter in the middle with a bright nucleus.
Hartung notes that he sees "a large elongated fairly bright haze with diffuse elliptical nucleus, and it looks as if it would be an impressive object for northern observers. 10.5cm shows it dimly."
Tom Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "8.3M; 18' x 8' extent; very large, N-S-oriented oblong with stellar nucleus; one end appears blunted; very faint IRR GAL N4248 (13M; 3' x 1.2' extent) 13' to NW with 15M star superimposed on W end; 50' to ESE of M-106 is faint oblong EL GAL N4346 just past 6.3M star (SAO 41141) !good supernova prospects!."
Sanford calls it a "large bright galaxy .. it has a fairly bright spiral arm, which can be seen extending from the body of the galaxy in a 10-inch with good atmospheric conditions."
Morales, using a 10-inch at 87x wrote: "extremely large; very bright with a bright, compact centre; extended in a north-south direction with a large, fuzzy outer envelope."
Houston recalls viewing the galaxy with a 10-inch and seeing a "very bright parallelogram shape with fragile spiral arms at the ends of the major axis." He notes that the nucleus appeared uniform with little variation in brightness - other observers using 8-inch scopes have reported M106's appearance as long and needlelike, and one saw a dark area near the nucleus. "So much for consistency" he concludes. A photograph showing many faint galaxies around M106 appeared in Sky and Telescope, April, 1991.
MacRobert calls it "big and bold in the 6-inch, very elongated north-south, with hints of irregularities around its ends. I've even spotted it through thin clouds! A 6th mag star half a degree east-southeast makes it fairly simple to locate. I haven't sighted any of M106's companion galaxies, but hunting them down would be a good project for an 8-inch under dark skies."
Phil Harrington (1990, Touring the Universe through Binoculars) calls it a "relatively large elliptical glow less than half a degree west of a 6th mag foreground star. The galaxy's nucleus appears decidedly nonstellar with higher magnifications ... it appears about [9' x 4'] when viewed thougfh binoculars."
Hubble: halo pa150, out core pa165.
ApJ 149,487: core pa145, hard to imagine pa110-115.
7x35mm - mod f, nrly circ, f *ar nuc. BS, 28Apr1992, TSP.
6cm - elong pa140 w/good concen to a f non*ar nuc. gx extends twd a m11.2 * 10' SE.
7cm - vbr fairly lg gx, prominent @ 30x. 50x: elong pa155, reaching SSE nrly to m12 * close to min axis that has m13 * SW of it. min axis reaches 1/2way out to m12 * NW of center. mod even concen in halo, strong even in core rising to mod br circ non*ar nuc. halo seems flattened on ENE- facing flank. BS, 15Apr1993, Anderson Mesa.
15cm - vbr & easily seen. 10'x7'. brtr twd center. great obj.
- easily seen three flds E of chi UMa. vbr, averted vis shows extns to 20' and sl less than half as wide. vlg br nuc that rises vabruptly from sm [well-]def core. *s can be seen all around the periphery and surrounding the nuc. occas gran.
25cm - vbr. 10'-12' long, bounded on N by m11 *. *ar nuc w/ sm vbr oval core less than 1' across. brtst part of halo 5'x2, smooth.
- core in pa110 w/overall pa160.
- 15'x4'.5. CBL, Roof.
30cm - 12+'x4' @ 140x. vbr but non*ar nuc. elong in pa140, but br area right around nuc is in pa115. this area 1'x0'.7 w/the prominent nuc on its SW edge: a sm dk shadow falls just on the SW side of the core. halo neet: broad brtr part extends NW from SErn end of elong inner core (1'.5 across) for 5', where it gets sl brtr. on symmetrically opposite side is a sim though much fntr counterpart. the W side generally sl fntr.
12-inch f/10 SCT (95x/52.8′, 218x/23.1′)
Nice and bright even at this low northern position. It displays a strong star like nucleus without a filter. The UHC filter let the core melt with its direct hazy surrounding. The galaxy stand quite out well with a fat dense oval body in a very elongated NW-SE direction, that runs out for almost 15' seen with averted vision (12" S/C – 95x). The northeastern side looks more flat towards the northeastern side. Two 11 magnitude stars can be seen, one on the extreme SE edge and one towards the outer northwestern flimsy side of the galaxy. It corresponds well with three galaxy sizes in my field of view 12" S/C – 52x.
Observing site: Pinnacles overlook
[12h 19m 0s, 47° 18m 0s] An almost (~ 70° tilt) edge on Sb spiral, with only a hint of mottling in the arms.
Observing site: Pinnacles overlook
[12h 19m 0s, 47° 18m 0s] An almost edge on Sc(?). Stellar nucleus barely seen. Burnham lists this as being an Sb, and as NGC 4258, not M 106.
The Messier objects
The Bennett objects
The Caldwell list
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