NGC 4631 (UGC 7865, Arp 281) Galaxy in Canes Venatici

Located at: RA 12 hours 42 minutes 05 seconds, Dec +32 degrees 32 minutes 18 seconds

Size: 15.4' x 2.6' Magnitude: 9.8 blue Class: SB(s)d sp HII

North is up

West to the right

Telescope:

 8" f5 Newtonian reflector

Camera:

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

Image:

Lumicon Deep Sky filter, 480 minutes (48 x 10 minute subs), 06/11/12/13/14/2008; seeing 2.3-3.5 FWHM per CCDStack

Processing:

CCDStack 1.3.7, Photoshop 7.0

Location:

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

Notes:

NGC 4631 is just 32.5 minutes NNW from the smaller, fainter, more chaotic NGC 4656. See the 14.5" version.

The small galaxy just north of NGC 4631 is NGC 4627 (2.6'x1.8', mag 12.5v, Cl: E4 pec).

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 4631

NGC 4631 = UGC 07865 = MCG +06-28-020 = CGCG 188-016 = Arp 281 = PGC 42637
12 42 06.5 +32 32 24
V = 09.2;  Size 15.5x2.7;  SB = 13.1;  PA = 86d

17.5": at 280x (14' field) this remarkable galaxy runs edge to edge across the 
field!  The surface brightness is unusually irregular with bright and dark 
mottling across the surface.  There is no well-defined core but a prominent knot 
is close following the geometric center along the north side and a second weaker 
knot is along the west side.  The north edge has an unusually "scalloped" 
appearance particularly along the west side due to dust and brighter splotches.  
The galaxy gradually bulges towards the center and tapers at the tips, 
particularly along the west end.  A mag 13 star is situated just north of the 
edge at the geometric center and N4627 appears to hover over this "starship" a 
couple of arcmin NW of center.

13": stunning galaxy, very bright, unusually large and interesting edge-on E-W, 
15'x1.5'.  A bright knot is east of the core and a faint knot is west of core.  
Appears very mottled along the major axis.  A mag 13 star is just N of the core.  
A companion system N4627 lies 2.6' NW of the center.

- by Steve Gottlieb
Contemporary Visual Observation(s) for NGC 4627
NGC 4627 = UGC 07860 = MCG +06-28-019 = CGCG 188-015 = Arp 81 = PGC 42620
12 41 59.7 +32 34 26
V = 12.4;  Size 2.6x1.8;  SB = 14.1;  PA = 10d

13.1": faint, small, slightly elongated SSW-NNE.  Located 2.6' NW of the center 
of the remarkable galaxy N4631 and is completely overshadowed by its beauty.

- by Steve Gottlieb