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Dragan
March 11th, 2013, 12:30 PM
Not a particularly in-depth article, but I thought I'd share it with the group.

http://www.spacetelescope.org/images/potw1310a/

lamperti
March 11th, 2013, 01:07 PM
There are 4 references to polar ring galaxies in a short paper of Deep Sky Observer 151: 20-23, 2010. Here they are in case you do not have access to that issue:

1 Galaxies and How to Observe Them, W. Steinicke and R. Jakiel, Springer, 2007
2 New Observations and a Photographic Atlas of Polar-Ring Galaxies, B.C. Whitmore, et al, Astronomical Journal, 100 (5), 1489-1755, 1990
3 NGC 2685: Spindle or Pancake? P.L. Schecter and J. E. Gunn, Astronomical Journal, 83: 1360-1362, 1978
4 Kinematic Modeling of Disk Galaxies III. The Warped “Spindle” NGC 2685, G. I. G. Jozsa et al, Astronomy & Astrophysics accepted for publication, October 2008.

Interestingly, there are 4 categories: Confirmed Candidates, Good Candidates, Possible Candidates and Systems Possibly Related to Polar Ring Galaxies. Listed in the paper is a Table with the NGC designations, Alternate Names, RA & Dec, Magnitude, Size and category.

Al

Steve Gottlieb
March 13th, 2013, 05:24 AM
The galaxy in the ESA/HST article is II Zw 28 = VV 790B and was discussed by Appleton and Marston in their 1997 paper "Multiwavelength Observations of Collisional Ring Galaxies" (http://articles.adsabs.harvard.edu/full/1997AJ....113..201A).

They described it as "one of the few empty ring galaxies without an obvious massive companion (Fig. 2)... The ring itself is extremely asymmetric, forming a crescent shape."

I took a look at it two nights ago in my 24-inch and no structure was visible at 282x but still a cool object to track down -- fairly faint, small, round, 20" diameter, broad concentration with no core or zones.

Marko
March 13th, 2013, 05:39 AM
In a 33" an observation of mine from about a year ago of CGCG 315-43 causes me to wonder in what catagory this ring was placed. It seems to be in a group from our 2D view of the area. Here is the note taken:

CGCG 315-43 Type: Glxy Position: 12 32 05.2 +66 24 10 Con: Dra
Date: 4/21/2012 Time: 01:00 Site: WSprDSR
Scope: 33ObF5.0 Eyepiece: 9mmNag Power: 472x
NELM: 6.6 SQM: 21.6 Seeing: 5 Transparency: 4
Description: 'RingGalaxy Tiny glow that clearly has darkened center. North
1/2 fov [5'] of Ngc4513. '


PostNote followup: Found it on page 206 of steve's link to the paper on rings. My connection timed out so I could only see it in a small picture to the left but the field of 3 galaxies was distinct enough to lead me to believe it is in that paper on page 206. MegaStar also refers to it as VV788

Jimi Lowrey
March 14th, 2013, 06:08 PM
I tool a look at this ring last night at 488x and 610x I could not resolve the ring. I think it will take a 10/10 night and really high power to see it. I keep thinking that it had the appearance of a PN.

FaintFuzzies
March 15th, 2013, 05:22 AM
This object is on page 90 in Jimi's Ring observing guide on my website.

FaintFuzzies
March 16th, 2013, 07:56 AM
I just refreshed the Ring Galaxy Observing guide with a few enhancements and a few minor corrections.