Author Topic: Can't see North American Nebula  (Read 210 times)

Brandon Belknap

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Re: Can't see North American Nebula
« Reply #15 on: January 13, 2018, 08:00:48 AM »
Great explanation Jon. Gives me a completely new perspective on how ive been interpreting magnitudes as point sources.

Nathan Mayienda

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Re: Can't see North American Nebula
« Reply #16 on: January 15, 2018, 01:47:02 PM »
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NGC 7000 (the North America Nebula) is actually a fairly easy low-power object for a rich-field telescope and a narrowband or OIII filter used under dark skies.

NGC 7000 is also readily visible with a binocular. IC 5067 and 5070 (the Pelican Nebula) is a bit harder to see.

http://www.perezmedi...ves/000822.html

http://oneminuteastr...america-nebula/

Here's a shot that I took at Cherry Springs State Park years ago using a Canon DSLR and a 135mm lens.

Dave Mitsky

Wow, what a lot of nebula you have there! How long where the exposures?

scenunhadef

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Re: Can't see North American Nebula
« Reply #17 on: January 16, 2018, 11:01:14 PM »
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Does it matter which hemisphere one is situated to see or
photograph the North American Nebula. Living in South Africa if i look
at the region (Cygnus )where the nebula is located through binoculars I dont see
anything except the characteristic pattern of stars in this region of the sky.
Even in a 5 sec exposure with my DSLR at 300 mm and ISO 12800 there is
absolutely no trace of anything nebulous in appearance.

That has always been a tough one for me to see. Problem is, I don't have real dark skies. I did find it a couple of years ago when it was very high in the sky. Uesd a 10" Dob with a 34mm EP ans a OIII filter. Saw both sides of it. Did not really see the NA nebula though.

kocewaffre

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Re: Can't see North American Nebula
« Reply #18 on: January 18, 2018, 01:02:52 AM »
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In Kimberly, South Africa, the nebula reaches only 15° or so above the horizon at culmination. That is well below the dreaded 2X airmass level which begins at about 30° there (2X airmass has twice as much air between you and the object than if you were observing it at zenith). The natural skyglow of the thick atmospheric layer will tend to hide the nebula from you. To make it worse, at this time of the month, the Moon rises just as the nebula reaches culmination when you will normally have the least amount of attenuation by the atmosphere. And all that is before you battle light domes from terrestrial sources.

I wouldn't give up on it yet. Try again later in the new Moon phase when there will be less Moonglow to interfere. It is difficult at first go, even for observers well-positioned in the northern hemisphere. It does get easier with repeated attempts. Can you see the more-condensed Veil nebula from your site? It is more noticeable than the North American. Once you confirm the Veil, you are ready for the North American. Better luck with your next sessions.
--------
C

And we who live in mid-northern latitudes will think about you while we struggle to see Omega Centauri and NGC 5128 and lament that we can't see Eta Carinae at all

Zachary Patterson

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Re: Can't see North American Nebula
« Reply #19 on: January 18, 2018, 08:11:45 AM »
Quote
Quote

NGC 7000 (the North America Nebula) is actually a fairly easy low-power object for a rich-field telescope and a narrowband or OIII filter used under dark skies.

NGC 7000 is also readily visible with a binocular. IC 5067 and 5070 (the Pelican Nebula) is a bit harder to see.

http://www.perezmedi...ves/000822.html

http://oneminuteastr...america-nebula/

Here's a shot that I took at Cherry Springs State Park years ago using a Canon DSLR and a 135mm lens.

Dave Mitsky

Wow, what a lot of nebula you have there! How long where the exposures?
It was a 5-minute-long shot at f/3.2 that I took on September 5th, 2005 using an unmodified Canon EOS Digital Rebel DSLR and a 135mm f/2 Canon EF lens.

Dave MItsky

rennlispuring

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Re: Can't see North American Nebula
« Reply #20 on: January 20, 2018, 01:56:40 PM »
I find many of the responses to the OP's question interesting and at the same time disturbing. They are a clear indication of just how poor today's skies are for the great majority of amateur astronomers.

Just as Nicknacknock did indicate, the NAN is a naked eye object without using any filters at all if your skies are truly dark. When reasonably high in the sky I always saw it as a faint, yet distinct, triangular mass in the milky way not far removed from Deneb...right from my backyard which is only 75 miles removed from Manhattan! That was back in the 1970's and such skies (Bortle class 0-1 & NELM 7.5) were still all very wide spread anywhere outside cities back then. It was a time when fully a third of the Messier objects could be spotted without any optical aid and even very modest binoculars showed them all quite easily.

So, the simple answer to the question of the NAN's visibility is nothing more than just needing honestly good skies...and good skies really don't begin unless your NELM is 6.5 or better.

BrooksObs

alssysenar

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Re: Can't see North American Nebula
« Reply #21 on: January 23, 2018, 05:18:03 AM »
I think what you were seeing is the star cloud corresponding to the nebula, not the nebula itself.

byhodete

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Re: Can't see North American Nebula
« Reply #22 on: January 31, 2018, 01:08:36 AM »
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Bingo. It is not a visual object, except under unusual conditions. It shows up well with cameras that are sensitive to H-alpha, such as modified DSLRs. I've also photographed it with unmodified DSLRs, with exposures measured in minutes rather than seconds.

To the contrary, NGC-7000 or the North American Nebula is indeed visible to people observing visually withbinoculars andsmall telescopes with low-power, wide field eyepieces, IF the skies are dark and moonless. A narrowband or O-III filter greatly enhances it's visibility under less than stellar skies. I see the OP though is inSouth Africa, which would place NGC-7000 very low in the northern sky. Even so, something must be wrong for him to fail to record any sign of it, perhaps his camera doesn't have enough sensitivity to hydrogen alpha radiation to record the nebula. I have seen it time and time again, through binoculars, small telescopes, even my 15-inch but only one piece at a time. It take at least a three degree true field of view to see it in it's entirety.

Taras

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Jeremy Swaine

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Re: Can't see North American Nebula
« Reply #23 on: January 31, 2018, 07:59:34 AM »
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I think what you were seeing is the star cloud corresponding to the nebula, not the nebula itself.


By no means. At the time I was already highly familiar with the field, knowing it precisely since following several variable stars in the immediate area for years. Likewise, switching from my naked eyes to small binoculars showed the exact same outline of the nebulous mass. I would add that the NAN was regarded as common naked eye sight by many observers way back when, as we all enjoyed nearly perfect skies (NELM 7.5-7.8).

BrooksObs

Chris Jiles

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Re: Can't see North American Nebula
« Reply #24 on: January 31, 2018, 08:47:54 AM »
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I think what you were seeing is the star cloud corresponding to the nebula, not the nebula itself.

Yes, to some extent that may be true. However, by holding up a narrowband or OIII line filter to the unaided eye at a fairly dark sky site, it is possible to see the nebula itself, as the filters will dim the stars. It is still best seen with some optical aid like binoculars or a rich-field telescope, along with the use of filters. Clear skies to you.

Dave Fair

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Re: Can't see North American Nebula
« Reply #25 on: January 31, 2018, 10:31:18 AM »
Quote
Quote

I think what you were seeing is the star cloud corresponding to the nebula, not the nebula itself.


By no means. At the time I was already highly familiar with the field, knowing it precisely since following several variable stars in the immediate area for years. Likewise, switching from my naked eyes to small binoculars showed the exact same outline of the nebulous mass
The standard unfiltered view of the North America Nebula both naked-eye and in binoculars is an amalgam of the nebulosity and the star cloud. I find they are absolutely impossible to separate naked-eye (without a filter) and very hard to separate with binoculars. Telescopes have enough magnification to resolve the star cloud well, making them relatively easy to separate, even without a filter.

As David Mitsky's fine photo shows, the southernmost and by far brightest part of the nebulosity has essentially no stars at all, yet it's trivial to see in binoculars in half-decent skies and fairly easy naked-eye in dark skies. It's instantly recognizable by its shape, reminiscent of the area around the Gulf of Mexico.

The far northern reaches, by contrast, have tons of stars and no nebulosity whatsoever. What the naked eye and binoculars show in the middle region is certainly more star than nebulosity.

"Blinking" this with a filter makes all of this obvious.

When viewed through a small scope at low power with a UHC or O-III filter, the North America nebula is pretty obvious in skies that are far from fully dark. But it's difficult or impossible from a typical suburb, even with a filter.

Jason Pederes

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Re: Can't see North American Nebula
« Reply #26 on: January 31, 2018, 01:11:36 PM »
Since this is the Beginners Forum and some have suggested wide field refractors for viewing the North American Nebula, folks may need to be reminded that if a mirror or right angle prism star diagonal is used, the view of the nebula will be the mirror image of a likeness of the North American map. Observers might not recognize Florida over where California is supposed to be! This of course is not a problem with binoculars or most reflecting telescopes.

I use a 6" F/5 refractor at low power with a O-III or UHC filter and a big Amici prism that gives a non-reversed view. Even casual visitors at a public star party can see it IF viewing is from a dark sky site. When visitors from the public say things like "I see the Gulf of Mexico!" you know they've seen the nebula.

proxbiovana

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Re: Can't see North American Nebula
« Reply #27 on: February 02, 2018, 07:30:36 PM »
Quote
Quote

Quote

I think what you were seeing is the star cloud corresponding to the nebula, not the nebula itself.


By no means. At the time I was already highly familiar with the field, knowing it precisely since following several variable stars in the immediate area for years. Likewise, switching from my naked eyes to small binoculars showed the exact same outline of the nebulous mass
The standard unfiltered view of the North America Nebula both naked-eye and in binoculars is an amalgam of the nebulosity and the star cloud. I find they are absolutely impossible to separate naked-eye (without a filter) and very hard to separate with binoculars. Telescopes have enough magnification to resolve the star cloud well, making them relatively easy to separate, even without a filter.

As David Mitsky's fine photo shows, the southernmost and by far brightest part of the nebulosity has essentially no stars at all, yet it's trivial to see in binoculars in half-decent skies and fairly easy naked-eye in dark skies. It's instantly recognizable by its shape, reminiscent of the area around the Gulf of Mexico.

The far northern reaches, by contrast, have tons of stars and no nebulosity whatsoever. What the naked eye and binoculars show in the middle region is certainly more star than nebulosity.

"Blinking" this with a filter makes all of this obvious.

When viewed through a small scope at low power with a UHC or O-III filter, the North America nebula is pretty obvious in skies that are far from fully dark. But it's difficult or impossible from a typical suburb, even with a filter.

My experience working this region and its variables largely contradicts this statement. The density and surface bright of the amassed Milky Way stars west of Deneb is pretty even overall, but is interrupted by the dark, un-illuminated, portion of the cloud whose outline frames the lighted portion forming the NAN. The embedded brighter portion of the Milky Way involves only a segment of the NAN's outline. What is seen with the unaided eye under truly good skies exactly occupies the outline of what is seen with even modest binoculars, or photos, with the brighter amassed stars clearly offset to one side. When seen under dark skies the the NAN also exhibits an overall somewhat higher surface brightness than its surrounding regions making it stand out rather noticeably. That being the situation, there is no question that it is the nebulosity itself that is visible to the naked eye under very dark skies since it matches the outline seen in photos and not simply the embedded stars and some of the brighter nebulosity, as anyone who has viewed this region under truly excellent skies on countless summer nights will attest.

BrooksObs

Corey Gibson

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Re: Can't see North American Nebula
« Reply #28 on: February 02, 2018, 08:28:08 PM »
From a suburban red zone, I have seen it very poorly with a 100mm f/6 refractor, 32mm eyepiece and a orion uhc filter.
I could discern the edges where the area was slightly hazy or maybe a touch brighter than the sky right next to it. I had to go back and forth leaving the area just to make sure my eyes were not fooling me. After three trips and seeing it each time
I was convinced I was seeing something.

unmoharib

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Re: Can't see North American Nebula
« Reply #29 on: February 03, 2018, 04:57:45 AM »
See North American Nebula (NGC7000) is bestfor me is a good 10X50 binocular in dark sky and no Moon here! You are lucky to have Large Magellanic Cloud and Small Magellanic Cloud!