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View Full Version : IC 2574 aka Coddington's Nebula



Preston Pendergraft
April 8th, 2013, 02:07 PM
I was thumbing through my new copy of Uranometria and I came across this object. I did a google search for it and only got research articles and astro photos. I did get a link to DeepSkyPedia which made references to visual observations, however two of three links were dead to the actual blogs or homepage that had contained the observation

The "nebula" is actually a dwarf galaxy and is a pretty low surface brightness object.

So anyone ever go for this one?

Clear Skies
April 8th, 2013, 03:01 PM
If the skies clear before midnight tonight I will give this one a go, it's part of my observing plan for this week (http://www.deepskyforum.com/showthread.php?343-Clear-Skies-in-France-A-Week-of-Observing). I expect it to be "on the limit" for my 12" SCT, I think I'll be lucky to pick up a faint, uniform glow. Perhaps a hint of the brighter (HII ?) region on the NNE side. Don't have an observation (or an attempt) logged for it yet.

569

lamperti
April 8th, 2013, 06:57 PM
Back in 1992, I went for this object with a 13" f4.5 reflector. I only saw a few faint globs in the area. However, it definitely needs to be re-observed with the larger aperture I have now.
Al

Jim Chandler
April 9th, 2013, 03:26 AM
IC 2574 was on the advanced observing list at the 2007 Texas Star Party, so I suspect quite a few people have taken a crack at it.
In my 25" f/5 at 77x on an okay night (T=6/10, S=6/10), I saw an ovoid glow with no internal detail.

Jim

Steve Gottlieb
April 9th, 2013, 07:02 PM
Here are two observations of Coddington's Nebula -- the first with my old 17.5" from 19 years back and a more recent one on Jimi's 48-inch. What a difference! By the way, Sue French reports seeing it in a 105/610mm Apo (Traveler), so it's visible with a small aperture.

48" (2/21/12): This large, low surface brightness dwarf irregular in the M81 group*extends roughly 10'x4' SW-NE with only a weak, broad concentration. The galaxy is dominated by a giant star forming/HII complex near the NE end of the galaxy. At 375x, four separate, compact knots were easily resolved within a 1.2' region, though the brighter glow from the entire complex spans roughly 1.5'x1.0' from WSW to ENE. The brightest and largest knot carries the designation IC 2574:[HK83] #15, from Hodge and Kennicutt's "An Atlas of H II regions in 125 Galaxies" in AJ, 88, 296 (1983). This high surface brightness knot is very bright, slightly elongated N-S, 20"x15", and is situated at the NW vertex of the four knots. #13/34 is a fainter irregular knot of ~12" diameter at the NE vertex. #35 forms the SE vertex and appears as a faint, round knot, only 8"-10" in size, just 24" SSW of #13/#34. The knot at the SW vertex is not listed in the H-K atlas, but is catalogued in NED as radio source NVSS J102844+682809. It appeared similar to #35, though slightly elongated, and is situated only 20" S of #15. At 488x, a 5th knot was seen ~30" SW of #15, and appeared as a very faint, ill-defined 15" glow (this region contains #17 and #19).

17.5" (3/12/94): faint, very large, elongated 5:2 SW-NE, 7.0'x2.5', low surface brightness, no concentration. Four faint stars are near the north side. There is a fairly bright nonstellar HII region which is clearly visible at the NE end as a high surface brightness knot.

Uwe Glahn
April 9th, 2013, 07:20 PM
When the sky is good enough the galaxy itself should be no problem also in smaller telescopes. With 16" I saw similar to Steve the bright HII knot at the NE. With higher mag I suspected a division within the knot but was not sure about this detail. Under excellent skies I could pick up a faint tail at the SW.

16", 100x-257x, NELM 7m0+
572

Clear Skies
April 10th, 2013, 12:02 PM
Observed IC2574 last night, but was able to only discern the HII region in my 12" SCT. Sometimes a hint of the faint glow of the galaxy itself, but no more than that. The HII region was evident and appeared a bit mottled.

Ciel Extreme
July 27th, 2014, 03:54 PM
Here is a sketch of Coddington’s nebula from my backyard, done a couple of days ago. The galaxy was about 40 degrees above the north horizon (with interference from my neighbour’s mercury vapour security light - good tarps attached to the fence make good neighbours, grrrrrr) I’ve included a DSS image at approximately the same scale for comparison purposes. A very neat galaxy!

1298

akarsh
August 12th, 2014, 06:52 AM
I observed Coddington Nebula with my 18" from reasonably dark (maybe ~ Bortle 3) skies near Atoka, Oklahoma (Texas Astronomical Society's observing site). This site is not as dark as the observing site I frequent in the Hill Country region of Texas (which might be ~ Bortle 2 on good nights). I recall it being low surface brightness, with some mottling, but I recall finding it brighter than IC 342. It wasn't very easy, but it wasn't difficult either -- nowhere as difficult as some of the other objects posted on these forums.

akarsh
August 12th, 2014, 06:53 AM
Here is a sketch of Coddington’s nebula from my backyard, done a couple of days ago. The galaxy was about 40 degrees above the north horizon (with interference from my neighbour’s mercury vapour security light - good tarps attached to the fence make good neighbours, grrrrrr) I’ve included a DSS image at approximately the same scale for comparison purposes. A very neat galaxy!

1298

Wow! That is a wonderful sketch, Mark. Makes me want to go back to this object and do a more careful observation.

Ciel Extreme
August 12th, 2014, 10:40 PM
Hey Akarsh

I boosted the contrast on the sketch in order to make sure it would show in the post. All the details were visible in my backyard observation, but it took about fifteen minutes for it all to “settle in”. Funnily enough, the next week at Grasslands National Park in southern Saskatchewan (a Canadian Dark Sky Preserve) with naked eye stars about one and a half magnitudes fainter than visible from my backyard, I found the galaxy much more difficult when I showed it to my observing bud Chris Beckett of the RASC. Strangely, when I had earlier emailed the sketch to Chris, he replied: “Wow, makes me want to go out right now and observe!” (ha, ha)

akarsh
August 13th, 2014, 12:30 AM
Hey Akarsh

I boosted the contrast on the sketch in order to make sure it would show in the post. All the details were visible in my backyard observation, but it took about fifteen minutes for it all to “settle in”. Funnily enough, the next week at Grasslands National Park in southern Saskatchewan (a Canadian Dark Sky Preserve) with naked eye stars about one and a half magnitudes fainter than visible from my backyard, I found the galaxy much more difficult when I showed it to my observing bud Chris Beckett of the RASC. Strangely, when I had earlier emailed the sketch to Chris, he replied: “Wow, makes me want to go out right now and observe!” (ha, ha)

I must admit that the sketch had the same effect on me; the other posts in this forum also have that effect. Next time, I want to try and observe the "Hubble's Rose" pair from the VV catalog -- found it in Steve Gottlieb's article in S&T this month.

When I observed this object, it was pretty low in the horizon. I'll try to bag it quickly next month before it descends.