NGC 3184 (UGC 5557) Galaxy in Ursa Major

Located at: RA 10 hours 18 minutes 17 seconds, Dec +41 degrees 25 minutes 27 seconds

Size: 7.4' x 6.9'; Magnitude: 10.4 blue; Class: SAB(rs)cd

North is up

West to the right

Telescope:

 8" f5 Newtonian reflector
Camera:

 ST-8XME, self-guided, binned 1x1, temp -25c, camera control MaxIm DL 4.56
Image:

Lumicon Deep Sky filter, 540 minutes (54 x 10 minute subs), 04/5/6/7/10/2008; seeing 2.0-3.0 FWHM per CCDStack
Processing:

CCDStack 1.3.2, Photoshop 7.0
Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)
Notes: Big flare from Mu Ursa Majoris (V=3.1) located about 40' West ... see this more recent processing in Photoshop CS 5.1

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 3184

NGC 3184 = UGC 05557 = MCG +07-21-037 = CGCG 211-038 = N3180 = PGC 30087
10 18 17.0 +41 25 27
V = 9.8;  Size 7.4x6.9;  SB = 13.9;  PA = 135d

17.5": fairly bright, large, slightly elongated ~N-S, large 4' halo has a fairly 
low surface brightness, very weak concentration, small brighter elongated core.  
A mag 11.5 star is at the N edge of the halo 1.8' from the center.  There is an 
impression of spiral structure but it is not distinct .  Located 40' W of Mu 
Ursa Majoris (V = 3.1).

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 3184
NGC 3184.  See NGC 3180. - Dr. Harold G. Corwin, Jr.
Contemporary Visual Observation(s) for NGC 3180
NGC 3184 = UGC 05557 = MCG +07-21-037 = CGCG 211-038 = N3180 = PGC 30087
10 18 17.0 +41 25 27
V = 9.8;  Size 7.4x6.9;  SB = 13.9;  PA = 135d

17.5": fairly bright, large, slightly elongated ~N-S, large 4' halo has a fairly 
low surface brightness, very weak concentration, small brighter elongated core.  
A mag 11.5 star is at the N edge of the halo 1.8' from the center.  There is an 
impression of spiral structure but it is not distinct .  Located 40' W of Mu 
Ursa Majoris (V = 3.1).

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 3180
NGC 3180 is a star cloud or HII region in NGC 3184's northwestern arm.  The
position in NGC (by Dreyer from LdR's observations) fits the star cloud 
better, but the HII region is brighter, though smaller.  The number may well 
apply to both objects or simply the general area of the arm where they are 
found.

There is no problem with the identification of NGC 3181 -- it is the brightest
HII region in NGC 3184, located southwest of the nucleus.
 - Dr. Harold G. Corwin, Jr.