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Dragan
October 15th, 2019, 06:55 PM
Object of the Week October 13th, 2019 – IC 1454 The Kings Ring

IC1454
Abell 81
PK 117+18.1

Planetary Nebula

Cepheus

RA 22 42 25.00
DEC 80 26 31.96

Mag: 14.0

Size: .6’ in diameter

NGC 6946 the Fireworks Galaxy. NGC 7380 the Wizard Nebula. NGC 7023 the Iris Nebula. These are the more common deep sky objects we think of when we think of surfing Cepheus. Even Mu Cephei, or Garnets Star deserves a mention. But an object I gave the unique moniker of “The Kings Ring”, I feel should be included in any list of objects in Cepheus.

IC 1454 is a planetary nebula located at the end of a ½ degree long chain of three 7th magnitude stars near the peak of the “house”. Nearly half a minute across and 14th magnitude in brightness, there is relatively little information available online about this object. George Abell in 1955 made a notation that IC1454 was discovered on the National Geographic Society Palomar Observatory Sky Survey being that it was never recognized before as a PN.

Interesting note, Abell cataloged this object as number 67 in his personal list. The Night Sky Observers Guide Vol. 4 also names IC 1454 as Abell 67. But every other reference I was able to find regarding this object identifies it as Abell 81. I couldn’t find a reason for the discrepancy. I don’t know if this is due to something as simple as a mistake or if the current Abell list as we know it doesn’t correspond exactly to his original list. Abell 67, as far as I know is a faint planetary in Aquila.

I came up with the nickname The Kings Ring the very first time I observed this object through my 25. I just thought it was fitting for a perfect little ring nebula in Cepheus the King.
In my 25”, the ring is fairly easily discernable. Without a filter at 250x and higher, the PN is easily seen with an obvious darkening. I have had best improvement using OIII and NPB filters helping give the nebula a more defined ring shape. I’ve never had a definitive sighting of the central star so easily seen in images. At higher power with good seeing, the ring itself appears rather irregular in both shape and brightness offering an extra dimension to this nebula.

IC 1454, or the Kings Ring, offers up an interesting view most nights of the year. Yes, Cepheus is home to more famous objects, but IC 1454 deserves to be among those objects. It’s a fine ring nebula that is visible in all manner of aperture and shouldn’t be ignored.

And as always,

give it a go and let us know!


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Steve Gottlieb
October 16th, 2019, 12:51 AM
You were on the right track about the Abell designations. His first paper was in 1955 (http://articles.adsabs.harvard.edu/pdf/1955PASP...67..258A) and included 73 planetaries as well as 13 globular clusters discovered by visual inspection of the POSS I. Of course, subsequently a few were found to already have NGC or IC designations. His second paper was published in 1966 (http://articles.adsabs.harvard.edu/pdf/1966ApJ...144..259A) and increased the total to 86 planetaries.

All the planetaries in the 1955 paper were renumbered (so the list stayed in order of increasing RA) and usually the early designations (such as Abell 67 for IC 1454) are discarded. I don't know why NSOG called it Abell 67, which is misleading.

Raul Leon
October 16th, 2019, 01:00 AM
Hi, here's my observation from 9/19/2009: Ic 1454 aka Abell 8 in Cepheus; magnitude:14 ; size:6' ; roundish and faint ; dark spot suspected in central area but not sure, seeing was not good on this night, OIII filter works well on this object. I should use more power on night with better seeing; I used a 14mm Meade Ultrawide eyepiece at 113x magnification with my 14.5 Starstructure Dob f/4.3 * I am going to make it a point to revisit this object soon, thanks for reminding me. 3663

Ivan Maly
October 16th, 2019, 01:34 AM
It was "small, round" as seen in my old 12" SCT at 230x on an SQM 21.7 night three years ago.

wvreeven
October 16th, 2019, 06:47 AM
With my 20” from fairly light polluted skies I have seen it as a round glow next to a bright star at 160x. OIII makes it easier to see. At 366x it nearly disappeared. I need to revisit this one under darker skies.

lamperti
October 16th, 2019, 11:33 AM
Very similar to yours, Ivan.
In 1997 with a 18", 286x + UHC, "Direct vision showed it to be round, relatively large, ball-like even glow."

Steve Gottlieb
October 16th, 2019, 05:12 PM
The angularity was subtle in my 18", but evident in my 24". I didn't use high power to try and see the central star, but it's apparently quite dim.

24" (10/3/13): at 225x using an NPB filter, IC 1454 (Abell 81) appeared fairly bright, round, 30" diameter, crisp-edged. The planetary displayed a relatively large, brighter rim that was unevenly lit, and a small (~12"), slightly darker center. Unfiltered the annularity was more difficult to confirm, though the rim appeared slightly brighter on the south side. A pair of 14th magnitude stars are just off the NE side and a mag 13.4 star is 1' SE. Situated 4.3' W of mag 7 HD 215867.

As far as the original discovery, that was quite awhile before Abell. Accomplished British amateur William Denning found IC 1454 in the summer of 1891 (probably while comet hunting) with his 10-inch reflector. He called it "rather a difficult object, except on a good night, though I picked it up with a power of only 40x. It is noteworthy as being situated in the midst of a region containing very few nebulae."

Howard B
October 17th, 2019, 04:05 AM
I have one observation of IC 1454/Abel 81 from 2009 with my 28-inch scope:

"...this is a terrific planetary. Perfectly round, obviously annular with a dark center but no visible central star. Easy to find and locate - best seen without any filter - this is doubly pleasurable after that last PN (G 124.0+10.7, which I could barely detect) 408x, 21.60"

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Uwe Glahn
October 17th, 2019, 08:05 PM
Nice and overlooked object Dragan. Here we go with my attempts:

4", 55x, UHC, fst 6m5+
visible even without filter, with 55x small and round, UHC filter with hardly improvements, best view without filter

8", 80x, fst 6m5+
not visible with 31x; with 80x visible just without filter; nearly no positive filter reaction; round glow with good defined edges but without dark center

16", 51x-450x, [OIII], fst 6m5
bright, also visible without filter, round, circular disc, sharply defined, faint double star at the NE

16", 250x, [OIII], fst 6m8
PN with faint ring structure, thick ring

27", 586x, fst 6m5+
bright object; asymmetrical and structured ring; faint CS
3666

27", 293x, [OIII], fst 7m0+
bright even in the unfiltered finder eyepiece; with [OIII] and 293x 5:4 E-W elongated; first knots within the ring; halo suspected with 172x and [OIII] but not sure visible

MikeWiles
October 30th, 2019, 09:11 PM
Observations from Portal, AZ on Oct 22, 2019

20" f/3, 84x - just visible as a nonstellar round glow. Two 7th magnitude stars to the east point to the nebula

20" f/3, 221x, 27.1' - Obvious round glow 30" in diameter. A 14th magnitude star is touching the NE corner of the nebula. No central star observed, no annularity observed unfiltered. UHC filter adds enough contrast that it appears to be darker in the middle.

obrazell
November 1st, 2019, 10:16 AM
I managed to see this with my UC 15 from fairly poor skies (SQM 20.9) at a star party this week in Suffolk UK. I noted a pale disk using an OIII filter and an Ethos 6mm eyepiece. It was faint but direct vision. No structure seen

Owen