M 106 (NGC 4258) Galaxy in Canes Venatici

Located at: RA 12 hours 18 minutes 57 seconds, Dec +47 degrees 18 minutes 31 seconds

Size: 18.8' x 7.3 Magnitude: 9.1 blue; Class: SAB(s)bc

North is up

West to the right

Telescope:

 8" f5 Newtonian reflector

Camera:

  ST-8XME self-guided, binned 1x1, temp -15c & -20c, camera control MaxIm DL 4.56

Image:

Red (Hoya 25A) filter, 300 minutes (30 x 10 minutes) 05/7/8/10/2007

Processing:

CCDStack 1.2, Photoshop 7.0

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes:

This image replaces a 100 minute red-filtered sequence from 06/04/2006. See the 14.5" version.

From the the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 4258

NGC 4258 = M106 = U07353 = MCG +08-22-104 = CGCG 243-067 = CGCG  
244-003 = VV 448 = PGC 39600
12 18 57.5 +47 18 15
V = 08.4;  Size 18.6x7.2;  Surf Br = 13.6;  PA = 150d

18" (6/4/05): two spiral arms are evident emerging from the large,  
very bright core.  On the west side of the core, a thin, gently  
sweeping arm defines the western edge of the galaxy.  At the southern  
end of this arm is a brighter knot or HII region.  On the east side  
of the core, a well-defined, thin arm juts out from the core towards  
the NNW as a linear extension.  The arm is brightest where it  
attaches to the core.  The core is concentrated to a fairly small,  
very bright central nucleus and the extensions/arms have a slightly  
mottled or lively appearance.  This is a Seyfert galaxy with a very  
active galactic nuclei.  The standard model for the core assumes a  
massive black hole.

17.5": very bright, very large, very elongated 3:1 NNW-SSE, 14'x4',  
large bright core concentrated to a very small brighter central  region.  
A thin bright spiral arm attached at the core extends  towards the NNW 
on the following side of the galaxy.  There is a  sharp edge along the 
west side of this arm.

13" (4/12/86): bright, very large, bright core, substellar nucleus,  
mottling near core.  A large bright knot is at end of the southern arm.

13" (3/17/86): very bright, very large, impressive!  Contains a  
nearly stellar core in a high surface brightness oval disk.

8": bright, very large, elongated, bright core.

- by Steve Gottlieb