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NGC 7023

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#1 Scanning4Comets



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Posted 13 October 2013 - 03:39 PM

I tried to see this with every eyepiece I had last Thursday, with and without my Orion Ultrablock filter and couldn't see anything.

Is this a diffucult object to see?

NGC 7023

#2 Astrojensen


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Posted 13 October 2013 - 04:35 PM

It's not at all difficult from a dark sky, but it's a reflection nebula, so it doesn't respond well to a light pollution filter at all. Under a mag 6 sky, it's unmistakable in a 60mm...

Clear skies!
Thomas, Denmark

#3 MrJones



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Posted 13 October 2013 - 04:45 PM

You probably mean the Iris Nebula by NGC 7023 although the nomenclature here is a mess. It's an almost pure reflection nebula (with very weak HII emission) so narrowband nebula filters do not help. But it is one of the few non-emission objects that Deep Sky/LPR/SkyGlow filters can help with as the reflected light is mostly blue due to the dust particle size that is reflecting the light. It's pretty bright and I've seen it easily in my 5" refractor - just catch it on a good night. With smaller apertures it looks like a fuzzy star. Also look for the inky blackness of the unlit dust surrounding the reflection nebula.

#4 Nick Anderson

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Posted 13 October 2013 - 04:55 PM

NGC 7023 (Iris Nebula) is one of my favorite reflection nebulae, probably my favorite if I had to pick one. If I remember correctly, when I was first working through the Caldwell list in 2012, it took me a few tries before I finally noticed the faint ghostly glow surrounding the bright 7th magnitude star at the center. If it were not for this star, the nebula would be a lot easier to observe...except for the fact that this is the star responsible for illuminating the nebula! At least for me with my 8-inch scope, NGC 7023 has been a hallmark object for my Orion SkyGlow filter. Although visible unfiltered, with the filter I could just barely detect subtle hints of varied brightness and shape.

-Nick Anderson

#5 GlennLeDrew


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Posted 13 October 2013 - 05:08 PM

This is one of the brightest reflection nebulae, due to both the brightness of the illuminating star and what I think is no small amount of forward scattering. (Dust lying between us and the star more efficiently scatters light than does dust behind the star--backscattering.)

From a reasonably dark site, a 15X70 bino readily reveals the halo of light surrounding the star. Similar brightness stars in the area serve as a comparison, for which there is no similar surrounding fuzz.

#6 stevecoe


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Posted 13 October 2013 - 05:23 PM

Here is an observation with a TV 102 (4 inch refractor) on a good, but not great, evening.

NGC 7023 TV 102 Antennas S=6, T=7 14mm 7 stars and faint, pretty large nebulosity, not much, averted vision makes it more prominent.

Hope that helps;
Steve Coe

#7 azure1961p


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Posted 13 October 2013 - 05:36 PM

This is my fav reflection nebula that shows structure in my 8" - no filters of course. Best mags hover around 200x. Nice - bright fir a reflection nebula and captivating structure seen through tantilizing mottling.


#8 Feidb


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Posted 13 October 2013 - 05:58 PM

MrJones sums up the initial impressions at low power and less than ideal conditions. It looks like a fuzzy star. However, on a great night with a bit more magnification, the nebulosity shows itself. I noticed a fairly distinct glow around that fuzzy star, but the conditions were quite good. Magnification was 102X using my 16-inch. I tried both a UHC and an O-III they blocked it out completely. Both filters were too harsh. I never tried an LPR.

It takes more of a dark and transparent sky versus aperture. It was our October 2012 Observer's Challenge and the range of scopes that spotted it proved as much.

#9 jgibson1@emich


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Posted 13 October 2013 - 06:49 PM

NGC7023 is a wonderful reflection nebula! I had my first good view of this target this past new moon weekend while at my dark sky site.

My 12" f/5 dob with a 17mm Nagler produced a very fine view. The central star appears fuzzy and different than all other stars around it. The skies of southeastern Arizona are dark and very transparent. These two traits allowed me to see a fair bit of detail. There was an obvious dark stripe through the nebulosity.

When the power was bumped up with the 9mm Nagler more subtle dark regions became visible. Mottling in the nebula around the star were obvious.

Given that this is a reflection nebula I didn't try any nebula filters.

Very clear and very dark skies are key to getting every bit of detail out of this target.

Clear Skies,

#10 David Knisely

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Posted 14 October 2013 - 01:38 AM

It's not at all difficult from a dark sky, but it's a reflection nebula, so it doesn't respond well to a light pollution filter at all. Under a mag 6 sky, it's unmistakable in a 60mm...

Clear skies!
Thomas, Denmark

This is not necessarily true. NGC 7023 is primarily a reflection nebula, and as such, it can often be helped at least to a mild degree by the use of a broad-band LPR filter like the Lumicon Deep-sky or Orion Skyglow. The improvement of the view is mild, but it is there. It is best seen under skies that are already at least moderately dark, as under heavier skyglow, the broad-band filters don't work nearly as well. Indeed, the outer faint loops around the central mass are definitely easier to see with the broad-band filters than without them. Clear skies to you.

#11 Bill Weir

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Posted 14 October 2013 - 09:20 PM

Thursday? Was the Moon still up or just set? If so then it would be difficult.

I had a very nice look at NGC 7023 with my 20" last Tuesday evening (Oct 8)about an hour after the Moon set. It was spectacular to say the least. It actually wasn't the highlight of the evening though because I was using it as a starting point of a star hop to Gyulbudaghian's Nebula. http://observing.sky...ct/GM_1-29.html Right now it's experiencing a brightening so Marcus you should give that a try also. Wait until the night has good transparency for both.


#12 Scanning4Comets



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Posted 20 October 2013 - 11:56 PM

Hi Bill,

I think the moon was present indeed. I'll try for it again on a moonless night.


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