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Thread: NGC 1265

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    Member Ciel Extreme's Avatar
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    NGC 1265

    Hello All

    I was observing Abell 426 tonight (Perseus galaxy cluster) and alighted on the field containing NGC 1265 and IC 312. This is the first time I’ve observed either of these galaxies. The night started out reasonably nice but started deteriorating and settled finally on some pretty mediocre transparency. At a magnification of 295x, I found NGC 1265 quite bright with an intensely bright core which overwhelmed the galaxy’s disk. I checked Steve Gottlieb’s notes regarding this galaxy which I am including below:

    “NGC 1265 = UGC 2651 = MCG +07-07-052 = CGCG 540-088 = 3C 83.1 = PGC 12287
    03 18 15.8 +41 51 28
    V = 12.1; Size 1.8'x1.6'; Surf Br = 13.2; PA = 165d

    17.5" (1/7/89): very faint, small, round glow. This member of the AGC 426 cluster is located just east of a mag 11 star and has a striking location. Forms a pair with IC 312 6' SSW.

    Guillaume Bigourdan discovered NGC 1265 = Big. 20 on 14 Nov 1884 and reported "mag 13.3, 15" diameter, slbM." His position is 5 tsec of RA east and 1.4' south of UGC 2651 = PGC 12287. Steinicke mentions this is the brightest galaxy discovered by Bigourdan.”

    Since I’m using an 18-inch telescope, I’m puzzled by the description “very faint, small, round glow”. Also, I didn’t see a bright field star to the west, though there is one about 2.5' south. Looking up the relevant field in Alvin’s “Observing the AGC”, there is no significant star to the west of NGC 1265 on either the DSS image or on Alvin’s accompanying chart. Has anybody else observed this galaxy recently and/or over the years? How would you describe the galaxy? Anyone know of a possible supernova in this galaxy?
    Mark Bratton
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    Member Steve Gottlieb's Avatar
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    Hi Mark, there's clearly a couple of problems with this observation though it was made so long ago (1989) that I'm sure I don't have my original notes anymore. I'm guessing the description applies to a different galaxy or there was some other mixup. For example I also described the companion to IC 312, which is catalogued in NED as 2MASX J03181640+4144057 as "very faint" the same night, although it is clearly a couple of magnitudes fainter than NGC 1265.

    Thanks for pointing this out. I'd say another observation is in order!
    Steve
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    Thanks for the response, Steve. You were able to pick up that galaxy southeast of IC 312 25 years ago? Nice catch!
    Mark Bratton
    18" f/4.5 Litebox reflector (travel scope)
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    Member Steve Gottlieb's Avatar
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    Mark, I notice on images of NGC 1265 there is apparently a star superimposed just a few arcseconds from the center. Was the star evident in your observation?

    As far as AGC 426, I wanted to mention Albert Highe's deep visual survey -- 137 galaxies observed with a 17.5" within 1° of NGC 1275!
    Steve
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    Hello Steve

    Very much so. In my notes for the night (below average transparency, faintest star visible from my backyard, mag. +5.7) I wrote: “NGC 1265 is pretty bright, with an intense star-like core embedded in a low surface brightness disk. It is round and north of a mag. 11 field star. IC312 is faint but consistently seen as an irregularly round disk, a little brighter to the middle.” So I suppose the star-like core was actually a star. It certainly appeared so... I passed over it a couple of times looking for NGC1265 before I detected the disk. That’s why I inquired about a possible supernova, though at the galaxy’s distance, a typical supernova would have been a few magnitudes fainter than the star I saw.

    The faintest of the Abell 426 galaxies I’ve been able to see so far is PGC 12358, immediately east of NGC 1270. The NED quotes a magnitude of 16.69. 137 galaxies is impressive indeed...
    Mark Bratton
    18" f/4.5 Litebox reflector (travel scope)
    22" f/3.3 SpicaEyes Slipstream reflector (LittleTime Observatory)
    25x100mm binoculars
    “The Complete Guide to the Herschel Objects” (CUP 2011)

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    Mark

    Just looked at Ngc 1265. I thought I could not see the galaxy but then realised that the star with the faint halo was the object. I think that the core is not bright but the bright dot at the centre of the galaxy is a field star.

    Anyway my observation is consistent with yours.

    I also could see the ic 312 object nearby which looked much more galaxy like!

    Mark
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    Member Steve Gottlieb's Avatar
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    Because of Mark Bratton's original post about NGC 1265, I took another look a couple of weeks back in my 24". I was surprised when I went to the field I immediately noticed IC 312 but was initially stumped on NGC 1265. *Then I realized a relatively large, diffuse glow surrounding a fairly bright star that is superimposed near the center of NGC 1265. *You can see the diffraction spikes on the star in this SDSS image -- it really overwhelms the nucleus of the galaxy visually. *NGC 1265 supposedly has a Vmag = 12, but that may include the star.

    NGC 1265.jpeg

    NGC 1265 was discovered visually by Bigourdan with a 12" refractor at the Paris Observatory, but I wondered how could he have noticed the halo surrounding the superimposed star but missed the more obvious IC 312 in the field?

    When I checked the original NGC position for 1265, I noticed it was somewhat off the galaxy and exactly 8' due north of IC 312? This suggested to me that he made some kind of positional error and actually discovered IC 312 instead. So I sent an email to Harold Corwin, who has copies of all of Bigourdan's measurements, and it turns out NGC 1265 has been misidentified for the past 100+ years! Here's his reply for those who are interested in the details ---

    "You're right. Bigourdan's measurements apply to IC 312, not to UGC 2651 = CGCG 540-088 = 3C 83.1, the galaxy we've been calling NGC 1265 all these years. He has two measurements on 14 Nov 1884 for "NGC 1265" = Big 20, +14.01s +01' 03.5" and +14.10s +01' 05.0" from an "Anonyme" star 9 at 03 11 20, +41 30 (1900), which is in turn +5m 30s, +23.2' from BD +40 687. The problem is right here because applying these offsets to the BD star lands us in an empty field somewhat west of UGC 2651. While I don't know the cause of Bigourdan's error, correcting the offset between the stars to +5m 30s, +15.2' puts us right on a star at the correct offset from IC 312. Going through SIMBAD, the stars turn out to be HD 19770 = BD +40 687, and HD 275043 is the 9th mag "anonyme".

    So, Bigourdan indeed measured IC 312, and not CGCG 540-088. This makes NGC 1265 = IC 312, so a "famous" NGC number on a well-known radio galaxy bites the dust."

    I assume this correction will eventually be incorporated into online catalogues (NED, HyperLEDA, SIMBAD), though the former "NGC 1265" is left without a NGC or IC designation.
    Steve
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    Hey Steve

    Thanks to you and Harold Corwin for clearing this little mystery up. I’m guessing, then, that the original, discovery identification of this galaxy should be Zwicky’s CGCG 540-088?
    Mark Bratton
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    Member Steve Gottlieb's Avatar
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    CGCG 540-088 will work or UGC 2651, though this galaxy has been called NGC 1265 for over 100 years (Corwin found a 1913 paper by Max Wolf identifying CGCG 540-088 as NGC 1265), so I doubt that will change in the near future.
    Steve
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    Just checked and sketched the field.
    UGC 2651 is indeed only a faint halo around a brighter foreground star. With a modern 27-inch conspicuous but as a first looking person with a uncoated 12-inch it could be indeed (to) difficult.

    27", 293x, NELM 6m5+, Seeing IV
    NGC1265.jpg
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  11. #11
    Member Steve Gottlieb's Avatar
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    That captures the view, Uwe. By the way, the foreground star was not even mentioned in the UGC notes, based on the POSS-1.
    Last edited by Steve Gottlieb; February 20th, 2017 at 09:51 PM.
    Steve
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    Do we know any more about this discovery?

  13. #13
    Member Steve Gottlieb's Avatar
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    Quote Originally Posted by Frink View Post
    Do we know any more about this discovery?
    I'm not sure what you're looking for, but here is Harold Corwin's summary from his web page on corrected NGC/IC positions and historical notes. Courtney Seligman also has a summary of the NGC 1265 = IC 312 situation here.

    NGC 1265 = IC 312. For over a century, this has been identified with the galaxy that has also collected the numbers 3C 83.1, UGC 02651, CGCG 540-088, and MCG +07-07-052. Unfortunately, this is not the galaxy that Bigourdan discovered and included as "Big 20" in his lists of "novae".

    Steve Gottlieb brought this to my attention early in 2017 after observing the Perseus Cluster with his 24-inch telescope. He picked up IC 312 (nominally found by Lewis Swift on 8 November 1888) easily, but goes on to say


    I was initially was stumped on NGC 1265. It took me a minute or two to notice
    NGC 1265 as a relatively large, diffuse glow surrounding a fairly bright
    star that is superimposed. The star is not evident on the DSS, but you can
    clearly see it on the SDSS, including its diffraction spikes. NGC 1265
    supposedly has a V mag ~12, but I'm guessing that includes the star, and the
    glow of IC 312 at V = 13.4 was more obvious to me.


    Looking into Bigourdan's observations, we find that his entry for NGC 1265 is referred to an anonymous 9th magnitude star 5m 30s east and 23.2 arcminutes north of BD +40 687. But there is no star that bright with those offsets from the BD star. However, eight arcminutes south, there is such a star, and IC 312 is at Bigourdan's measured offsets from it (+14.06s, +01'04.3" from two observations on 14 November 1884). The eight arcminute error in Bigourdan's estimated offset from the BD star is currently inexplicable, but it is clear that Bigourdan discovered IC 312 and not UGC 02651.

    So, I've renamed the galaxies in my position tables. NGC 1265 is now identical to IC 312, and UGC 02651 is called "IC 312 comp".

    However, this is going to be a difficult change to push beyond the small group of NGC historians -- the literature from at least 1913 (when Wolf and Kaiser published positions of Perseus Cluster galaxies in Veroff. Heidelberg 6, 131) onwards accepts UGC 02651 = 3C 83.1 as NGC 1265. Yet it is abundantly clear that the NGC 1265 identity of this galaxy is a mistake, so we're just going to have to live with the confusion. (Contrast this with NGC 4874, which see, where I've suggested sticking with the traditional identification. There are good reasons for that, of course, though they are not quite as clear as the ones leading us to NGC 1265 = IC 312.)
    Last edited by Steve Gottlieb; September 11th, 2017 at 12:05 AM.
    Steve
    24" f/3.7 Starstructure
    18" f/4.3 Starmaster
    Adventures in Deep Space
    Contributing Editor, Sky & Tel

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