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I've read where older people tend to see green in planetary nebulae, where younger ones see more blue. I'm 55 and see green in the Saturn nebula. I haven't seen the blue snowball in a while so can't say.

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So what I saw was my imagination? If so then I will try to use my imagination a lot more when I observe,that way I can see more than I thought! My wife had a look and she saw Blue in it to. My 21 yr old daughter said it looked blue. Imagination runs wild in my family!

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It is kind of a bluish-green coloration that is difficult to describe, as it is almost on the border between blue and green. At times, it is *almost* an emerald green, but other times, it has a more bluish cast. Here is a drawing I did of the Saturn Nebula (NGC 7009) which I have tried to duplicate the color.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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Anything else that has some color?
Doug

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I wish I could look through someone elses eyes. I feel I have excellent colour vision during daylight. I am posting this while standing in our shop surrounded by colourful candy packets, magazines and luridly coloured Coke and other soda bottles and point of sale advertising. The whole place is awash with bright colours. I feel like I am percieving them with all the intensity they have to give.

Observing at night???

Black and White only I am afraid. Sure I can see that Alberio is a differetnt colour pair and Aldebaran and Betelgeuse have an amber tint but thats the extent of my astro colour perception.

I can't help but feel that much like those who claim to see the central star of m57 in their 10inch are using averted imagination, that those who describe colours with the 'ish' tagged onto the end of the colour decription are using a bit of imagination too.

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In addition to the DSOs already mentioned, NGC 40 in Cepheus, NGC 6826 in Cygnus, NGC 6891 in Delphinus, NGC 1535 in Eridanus, NGC 2392 in Gemini, NGC 6210 in Hercules, NGC 6369 in Ophiuchus, and NGC 6445 and NGC 6818 in Sagittarius display some color to a greater or lesser degree.

Dave Mitsky

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Now see, that's what I mean. I have 7 out of those 9 logged (no 6445 or 6891), and the only mentions of color are "gray", "no color seen", "colorless" and "barest hint of washed-out avocado" (6818).

Sigh.

-- Jeff.

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Nikon 18x70s / UA Millennium                                       Colorado:
Solarscope SF70 / TV Pronto / AP400QMD                       Coronado SolarMax40 DS / Bogen 055+3130
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.......It'd be interesting to see what color you get with Uranus when it's reasonably close. I do get a fairly well-saturated blue-green there.

Cheers,
-- Jeff.

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Looked at Uranus in my old 12" at 300x around this time last year and shared the views with SDAS' Michael Murphy, Dave Brannigan and Paul(Lunartic). It was a nice small disc....A nice small white disc

The other lads thought it was a beautiful light green

Philip Larder thought white Saturn was a lovely shade of cream and Darragh the IFAS webmaster thought white Mars was a lovely salmon pink

I think a lot of it stems from different peoples colour perception and also peoples perception of colour. What I mean by the latter is that perhaps I am seeing the same view as many others but when they see a white mars with a mild tint of salmon say, they call it salmon coloured mars whereas when I see a white mars with a mild tint of salmon, I call it white mars and might barely conceed that there was a touch of salmon, but to me it wasn't enough to warrant me describing the colour as anything other than white. I'd be more inclined to call it a warmer white or a colder white as the case may be but I am just not seeing enough colour tint in objects to carry me over the threshold from describing them as anything other than white in the case of planets or shades of grey in the case of DSO's.

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Keith D.

Knightrider - 16" Meade Lightbridge - See Here
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It looks like planetaries are another object - like galaxies - that should be saved for dark site observation. Red zone is for Luna, planets and open star clusters.

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Granted, everything looks better under dark skies, but if I can see it--even a hint of it--I'm trying for it under my red skies. Sure, I can only see galactic cores, but that's something! I don't know how long I've stared at M51, teasing out which spot belonged to the main galaxy, and which to the companion. For me, that's all part of the fun.

Being limited to planets, the moon, open clusters? I'd get bored of hunting pretty quickly! Searching for new nebula is one of my favorite red-zone activities--I get impatient when the moon is full.

And I totally agree with you--when I get to a dark site, nebula, galaxies, and clusters are all I'm interested in. I just wouldn't want anyone considering getting into astronomy to think they can't see DSO's from LP skies.

Can't wait to try for the Blue Snowball!

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Tim

Zhumell Z10 dob
Meade 60mm refractor
Zhumell 1.25" eyepiece and filter kit
Zhumell sky-glow, UHC, and OIII filters

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I've definitely seen better color saturation in planetaries - even the Ring and Dumbbell - at a dark site. (Or is that "colorfulness" or "chroma"? Whatever...) It looks like planetaries are another object - like galaxies - that should be saved for dark site observation. Red zone is for Luna, planets and open star clusters. I've meant to focus on planetaries at some time in the near future. I have a 5-filter wheel that I can load with DSO filters for quick comparison. I might do that, though a quick flash between no filter and OIII might be the best bet in locating the critters, using a Zoom eyepiece to go to higher powers for a better look. I might even mount the 8" Newt on my CG5 so I can have tracking. (GEMs are a bother, though. )

Clear Skies,
Mike

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If you can get properly dark adapted, many planetaries will show good color even under some light pollution. In fact, on nights with the moon in the sky, I will go after some planetaries because they have enough 'punch' in their light to continue to be easily seen. I will really kick up the power to very very high levels to compensate for the poor resolution of averted vision, allowing me to see some details which I don't usually get to observe. A couple of nights ago with the 9-day old moon in the west, I had NGC 7662 in my NexStar 9.25 at 480x, and it looked quite nice. It showed the clear overlapping two-shell structure of the distorted inner oval ring superimposed on the diffuse more circular main shell. I have gone even higher in power on objects like NGC 7009 or NGC 6543. If I want to see color, I stay fairly low in power, but if I want detail in some of the brighter planetary nebulae, I will go as high as the seeing will allow. Clear skies to you.

--------------------
David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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Granted, everything looks better under dark skies, but if I can see it--even a hint of it--I'm trying for it under my red skies. Sure, I can only see galactic cores, but that's something! I don't know how long I've stared at M51, teasing out which spot belonged to the main galaxy, and which to the companion. For me, that's all part of the fun.

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Being limited to planets, the moon, open clusters? I'd get bored of hunting pretty quickly! Searching for new nebula is one of my favorite red-zone activities--I get impatient when the moon is full.

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And I totally agree with you--when I get to a dark site, nebula, galaxies, and clusters are all I'm interested in. I just wouldn't want anyone considering getting into astronomy to think they can't see DSO's from LP skies.

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If you can get properly dark adapted, many planetaries will show good color even under some light pollution. In fact, on nights with the moon in the sky, I will go after some planetaries because they have enough 'punch' in their light to continue to be easily seen. I will really kick up the power to very very high levels to compensate for the poor resolution of averted vision, allowing me to see some details which I don't usually get to observe. A couple of nights ago with the 9-day old moon in the west, I had NGC 7662 in my NexStar 9.25 at 480x, and it looked quite nice. It showed the clear overlapping two-shell structure of the distorted inner oval ring superimposed on the diffuse more circular main shell. I have gone even higher in power on objects like NGC 7009 or NGC 6543. If I want to see color, I stay fairly low in power, but if I want detail in some of the brighter planetary nebulae, I will go as high as the seeing will allow. Clear skies to you.

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I wish I could look through someone elses eyes. I feel I have excellent colour vision during daylight. I am posting this while standing in our shop surrounded by colourful candy packets, magazines and luridly coloured Coke and other soda bottles and point of sale advertising. The whole place is awash with bright colours. I feel like I am percieving them with all the intensity they have to give.

Observing at night???

Black and White only I am afraid. Sure I can see that Alberio is a differetnt colour pair and Aldebaran and Betelgeuse have an amber tint but thats the extent of my astro colour perception.

I can't help but feel that much like those who claim to see the central star of m57 in their 10inch are using averted imagination, that those who describe colours with the 'ish' tagged onto the end of the colour decription are using a bit of imagination too.

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Re: central star in M57. Rather than just dismissing some claims as "averted imagination, I think we may have to take a step back here and look at some facts. Like color sensitivity, light sensitivity in the human eye varies widely from person to person (sometimes as much as a full stellar magnitude, depending on age, physical conditions, and experience with "working the faint end"). M57's central star is about magnitude 15.2. The exact limiting magnitude of the telescope/eye combination also varies widely depending on magnification, local observing conditions, and eye sensitivity. A good 10 inch under optimal dark-sky observing conditions and at moderate to high power should be able to reveal stars down to a range from magnitude 14.9 to perhaps as faint as 15.8, again depending on the observer and the local conditions. This level of performance has been verified by a number of experienced amateur astronomers, so I personally have no reason to doubt this. This puts any claim of seeing the central star in a 10 inch aperture well into the realm of possible rather than dubious.

While the central star is difficult to say the least, if one says that claims of sightings of the central star in M57 in a 10 inch is just due to "averted imagination", that may be going too far. While sighting the star tends to be a somewhat rare experience, many well-known and reputable amateurs have seen the star in scopes of that size. The keys to doing this are: 1. Use of *very* high power (over 300x), and 2. Observing for an extended period to wait for moments of stable seeing. Seeing tends to blur the Airy disk of the central star enough to allow it to blend into the faint glowing nebulosity in the interior of M57, so most of the time (even in some surprisingly large telescopes), the central star remains invisible. However, higher power dilutes the central glow somewhat and also helps improve the ability of the eye to detect fainter stars. In addition, waiting for those moments of good seeing will allow the star to "pop out", at least briefly.

To be frank, up until a few years ago, I too was more than a little skeptical of the claims for seeing M57's central star in something as small as a 10 inch. I had not seen the central star even in a 30 inch Classical Cassegrain, and one of my Astronomy professors claimed he had never seen it even in the Steward Observatory 90 inch on Kitt Peak. However, once I finally saw how the star actually behaved in a 20 inch one night, I knew what the problem was and exactly how to look for the star. In that big scope at something over 300x, the star started out shining steadily, but then abruptly vanished as if it were suddenly shut off. When I watched for a while, I saw that when seeing got better, the star reappeared again, so catching the star when the seeing was good was the primary key to success. I spent a lot of time with my 10 inch at between 350x and 500x, and finally saw it faintly appearing and then abruptly vanishing just like it had in the big scope. Indeed, I got startled several months back, when the central star abruptly appeared in my 9.25 inch SCT, along with a few stars in the area that had magnitudes in the 15.3 to 15.6 range. It just goes to show that when working the faint end, there are limits, but they tend not to be hard and fast. The same goes for reports of color in some deep-sky objects. Some can see the color and some cannot, so one should be just a little careful when considering the possible use of the term "averted imagination". Clear skies to you.

--------------------
David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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So what I saw was my imagination?

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It always pays to be conservative in estimates and impressions just because the line between threshold detection and "imagination" can really get kind of blurred.

That said, dont sell yourself short...


Color is a tough topic in visual astronomy. So much varies from one observer to another that it can really be said to a degree that its pretty subjective. Not because the object changes composition of course, but because whose to say where anyones color detection kicks in and kicks out.

NGC6543 - Everyone sais blue green, green, and so on. I saw peach. Greyish peach. I had to admit after a certain point i saw other colors too. Based on that, I can infer I was merelly seeing GREY and the multitude of hues that make up this neutral value. My eye/brain essentially through out through out its best guess - at any one particular moment.
My scope is 8" aperture.

M-42 is a funny case in point. Grey - just grey and bright "deepsky grey". Then one evening - wow - the interior "wedge" of light that looks like a sheet of tufted clouds had this funky blue gree. IT reminded me STRONGLY of the mint green in some chocolates when you break them in half and the minty green filling is showing.

Blew me away. Grey forever took a holiday on that nebulas interior with me. Now its standard perception. An OIII just makes it all the sweeter.

But something odd happened - and this especially with the OIII...

All of a sudden the streamers and some of the outer reaches of the gaseous shell had these deep purple brown tones.

No way I thought. I'm seeing RED of M42 through my 8" reflector???

Cant be.

IT was persistent. The green was the chief dominat color - the darker steamers were purple brown.

Im an artist. I know a thing or two about color. Much as I loved the FAT idea of making out the reds in my 8" aperture - I had to test perceptions here. I knew too too much about doublestars making many people see GREEN stars- even lavender.

So heres the acid test....

Next time out on M42 I ooked good and hard. Yep - there it was - that lovely mint green. Fair enough - and then those ruddy purple red browns....


hmmmmm....


OK - so lets do a contrast check here. What if the GREEN of the nebula is causing a contrast effect with the grey streamers causing them to appear its color opposite?

So this time I let m42 drift by - BUT - to test the effects of contrast I make sure those lovely purple streamers show - WITHOUT the green interior.

The results were so strong I was embaressed. There wasnt a peenies worth of red in ANY of those streamers in any hue. It was a wonderful glowing grey streamer. Period.

I reintroduced the green interior - WHAMO - I saw the purple streamers again.

Lose the green though and again the streamers just turned colorlessly grey. Pretty, intriguing, captivating and engaging - but grey.

Ever since that day whenever I hear of ANYONE talking about reds in any nebula I wonder if there perceptions would be altered if the grren was removed from the equation.

Then again - its altogether believeable - even PROPER - that red should show through larger apertures. Why not Its gotta pop up sooner or later. In those cases though the contrast effects are stronger too.

I personally think its a little of both often.

Then theres M15...

Under a decent connecticut country dark sky the damned thing is gun blue grey. The blue again and again is so strong it makes me step back and question it, but i laugh because it just is what it is. Why isnt M13 BLUE too? IS M15 just the right magnitude level to kick in my blue receptors? But its there in my 13" tele too. Its pretty pronounced - no peaches or other ridiculous spurious colors - but that blue gun grey.

Other planetary nebula show colors to me in the blue-green realm - but nothing like the edible - m42 interior. The Eskimo has a decent blue grey grey cast for example. The snowball planetary is alas, blue to me too.

The bottomline for myself, I generally shrug most of the time with the color issues - especially when someone tells me the color of a galaxy - and through a medium aperture scope!!! There are REAL detections to be had, but there are a lot of prior suggestion moments, spurious color moments and so on.

Who knows...maybe m15 is blue for the make up of its stars - I doubt it though as globulars are pretty old in general. With regard to NGC6543 showing me shades of peach. I'll believe its real when i see the pit.

Pete

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OK - so lets do a contrast check here. What if the GREEN of the nebula is causing a contrast effect with the grey streamers causing them to appear its color opposite?

So this time I let m42 drift by - BUT - to test the effects of contrast I make sure those lovely purple streamers show - WITHOUT the green interior.

The results were so strong I was embaressed. There wasnt a peenies worth of red in ANY of those streamers in any hue. It was a wonderful glowing grey streamer. Period.

I reintroduced the green interior - WHAMO - I saw the purple streamers again.

Lose the green though and again the streamers just turned colorlessly grey. Pretty, intriguing, captivating and engaging - but grey.

Ever since that day whenever I hear of ANYONE talking about reds in any nebula I wonder if there perceptions would be altered if the grren was removed from the equation.

Then again - its altogether believeable - even PROPER - that red should show through larger apertures. Why not Its gotta pop up sooner or later. In those cases though the contrast effects are stronger too.

I personally think its a little of both often.

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When I saw reds and yellows in M27 and M57 through my 10" Newt at a dark site, I had evidence to show that the colors were indeed there. Both nebulae looked mostly pale light-gray with some red and yellow hues, not really green at all. My friend's computer monitor and his photos through a 4" APO showed the exact same colors at the same time and site. My wife and daughter saw the same colors through my telescope that I did. I think that in some cases, like mine, what you see is what there is. I don't think visual contrast effects and the power of suggestion have much of an effect on computer monitors and CCDs.
Mike

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Celestron 10" f5 Newt on 1stBase (DSO)
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Two things Dave!!

Thats the most spot-on color rendition i have ever seen of a glowing nebula. You really really nailed it. If you've got more - would you show some?

Too - [and two] Thats a nice piece on seeing m57's star. It's hopelessly out of my reach through my 8" but its a really engaging read to see that your 9.25" could nail it as well. After seeing 15V - and lucky to do so - in CT - its utterly off my radar. I cant envision making that same observation with a veil of gas as a backdrop.

Hats off to you though Dave. Sometimes the feeling of success isnt had in the personal execution of the observation, but in the satisfaction that the guy next to you pulled it off!!

Thats so cool!!! And how many times has it been written that its really the domain of much larger scopes. Theres lots to be said for being a good observer, lots to be said about effective technique too.

Pete

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Thanks a bunch for the complements. Well, I have my rendition of the Cat's Eye (NGC 6543) on another thread in the Deep Sky Observing forum, but here is the Eskimo Nebula. The color saturation on this drawing is quite a bit higher than what the eye tends to generally show visually, but when one finally gets the color right, why not flaunt it? Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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FWIW I have read that the Blue Snowball has the highest surface brightness of any planetary nebula observed from terra firma. Seems to fit the bill for me. BTW, it definitely appears blue in color in a 10-in newt and a 9.25 S/C, the last 2 scopes I observed it with.

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I think there is a little one in Ophiuchus (NGC 6572 "the Blue Racquetball nebula" if memory serves) which might tie or even beat the Blue Snowball (NGC 7662) for high surface brightness and really prominent color. That one looks almost lime-green to me with only a little bit of bluish color in it. Try and catch it before it gets too low and see what you think of it. Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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I think there is a little one in Ophiuchus (NGC 6572 "the Blue Racquetball nebula" if memory serves) which might tie or even beat the Blue Snowball (NGC 7662) for high surface brightness and really prominent color. That one looks almost lime-green to me with only a little bit of bluish color in it. Try and catch it before it gets too low and see what you think of it. Clear skies to you.

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Another little Pn guy down there in Ophiuchus is NGC 6369 A.K.A. the "Little Ghost Nebula". A little bit more of a challenge but pretty doable under favorable conditions for most folks. I've observed it many a times in my 8" dob but mostly from my local dark sky site.

Clear Skies to You All!

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Best,
Dain
Adirondack Mountains (my true dark sky site)
@ Cedar River Flow



Local Site


Clear Skies?

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Pete,

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When I saw reds and yellows in M27 and M57 through my 10" Newt at a dark site, I had evidence to show that the colors were indeed there. Both nebulae looked mostly pale light-gray with some red and yellow hues, not really green at all. My friend's computer monitor and his photos through a 4" APO showed the exact same colors at the same time and site. My wife and daughter saw the same colors through my telescope that I did. I think that in some cases, like mine, what you see is what there is. I don't think visual contrast effects and the power of suggestion have much of an effect on computer monitors and CCDs.
Mike

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Geez with that many "emoticons" or whatever the cartoon things are, a guy just has to respond...

Mike, true enough - there is real color to be had. Just as real however I'd imagine is pseudo-color. When the eye-brain is working that close to the limit, and the amount of cerebral "noise" is thrown in the mix, false color and contrast effects are probably a lot more common than you give credit.

Atleast for myself, I've proven the phenomenon. But, again - thats with my eye-brain. As Knisley mentions - this can vary widely from one observer to another.


You want a tip off for your own sake? If you see blue, then green then yellow - you're probably seeing the real deal. When you see reds and purples I'd beware of a color contrast effect. It's simple enough to do if you can manage to isolate a color from another.

With regard to monitors showing you only whats really there...

Thats not really true. Indeed, because the vividness of any one color [or more] can be so technicolor brilliant, areas that normally have neutral color values [grey or white] will take on a cast that isnt accurate to the original image.

But again, this is simple enough to test -usually - just merelly isolate the color you think is color. Go into photoshop and take the blood out of the blue and see if the red in the image stays red. If so, you're seeing the real deal.

In cases of gross certainty [with no ego involved] where the colors are just so simply the colors they appear to be, well no you dont need it. When you see watercolor or light pastel shades of colors.... test it out. Or dont.

At anyrate, where there is color be it monitor or real life, there are contrast effects from minor to profound.

Pete

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Thanks David, the question mark I had in my notes about the central star in M 57 has been erased. I've looked at this object numerous times w/10" SCT (at dark sky site) and (per notes) I claimed to have seen a "flicker" of starlight in the center. I always figured it was due to looking at it for long intervals; that light retention factor, but then that type of light wouldn't "flicker/glimmer". Thus my notes will now state that I've been flashed by M57's central star. AND I do see color (green and yellow) in the ring.

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I can't help but feel that much like those who claim to see the central star of m57 in their 10inch are using averted imagination, that those who describe colours with the 'ish' tagged onto the end of the colour decription are using a bit of imagination too.

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When I posted this thread I stated a simple observation that I had made and followed with a simple question. I never imagined it would cause such debate. Being relative new to the hobby and fascinated by it I am a little bit caught off guard by this. All I know is that I saw some color and so did my wife and daughter. Maybe my wife and daughter and I saw an illusion caused by turbulence or some atmospheric condition. Maybe some people are able to see color in things that other people don't! For my age I still have pretty good vision and am required to take a color blind test every three years for my job,and I have always passed with flying "colors". The next time I have my scope out I will look again to see and look carefully cause now I have a little doubt now after this post.
Clear skies
Doug

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Well, the problem is that the spectra of M57 has little in the way of emission that would give a truly yellow color, although an odd mix in sensitivities might give it an unusual hue. The strongest M57 line is the OIII line at 5007 angstroms (blue-green) with the second strongest the NII/H-alpha complex of lines deep in the red around roughly 6563 angstroms. The third strongest is the other OIII line at 4959 angstroms (blue-green) and the fourth is H-Beta in the blue. One should see a dominant bluish-green color unless one has an unusually strong red response to their eyes, where a dim red or reddish-orange color might come out. Most of the color images that are done properly mainly show red and bluish-green colorations unless they are saturated enough by long exposure to show something else. The largest telescope I have ever used on M57 was a 30 inch, and in that scope, the nebula showed a nice bluish color with just a hint of green to it. I have seen faint reds in IC 418, PK64+5.1 (a.k.a. Campbell's Hydrogen star) (well, a deep reddish-orange anyway), parts of M42 and parts of M8, but not in M57. Clear skies to you.

--------------------
David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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When I posted this thread I stated a simple observation that I had made and followed with a simple question. I never imagined it would cause such debate. Being relative new to the hobby and fascinated by it I am a little bit caught off guard by this. All I know is that I saw some color and so did my wife and daughter. Maybe my wife and daughter and I saw an illusion caused by turbulence or some atmospheric condition. Maybe some people are able to see color in things that other people don't! For my age I still have pretty good vision and am required to take a color blind test every three years for my job,and I have always passed with flying "colors". The next time I have my scope out I will look again to see and look carefully cause now I have a little doubt now after this post.

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The Blue Racquetball Nebula is the same object as the Emerald Nebula, which is a far more appropriate name for observers who see it as green. This is the only planetary nebula that appears green to my eyes. The Emerald Nebula, a very high surface brightness planetary as David mentioned, is quite young and is thus "optically thick". The UV radiation that its central star produces is largely absorbed and reemitted at the chief nebular wavelength of 500.7 nanometers (OIII lambda).
http://www.delphes.net/messier/planetar.html

Dave Mitsky

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For the name, I didn't see a formal name for it in my old Sky Atlas 2000.0 Companion. I just went with the first thing which Google came up with when I typed in NGC 6572. I had to go down quite a ways to find it listed as "The Emerald Nebula", and then, only as a secondary to the first Racquetball name. The object is very interesting, as at very high power during moments of excellent seeing, it shows an oddly shaped distorted inner oval ring-like shell which is kind of strung-out in a bar-like shape. I once noted a possible central star, but the observations on Doug Snyder's Planetary Nebula Home page which might confirm this are no longer accessible. The page on planetaries has been hijacked by some group out of Turkey, so the URL doesn't lead to his site anymore. Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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I have seen faint reds in IC 418, PK64+5.1 (a.k.a. Campbell's Hydrogen star) (well, a deep reddish-orange anyway), parts of M42 and parts of M8, but not in M57.

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I have seen faint reds in IC 418, PK64+5.1 (a.k.a. Campbell's Hydrogen star) (well, a deep reddish-orange anyway), parts of M42 and parts of M8, but not in M57.

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The same goes for me but with M42 and M8 the color was more on the pink side.

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I have seen tinges of light red in M42 in my 10", though mostly it is pale green. M8 was pale green or light gray for the most part. I don't recall red or pink in the Lagoon. But I did see light red/yellow in M27 and M57.

Mike

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Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!

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Dave Mitsky,

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I have seen faint reds in IC 418, PK64+5.1 (a.k.a. Campbell's Hydrogen star) (well, a deep reddish-orange anyway), parts of M42 and parts of M8, but not in M57.

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The same goes for me but with M42 and M8 the color was more on the pink side.

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I have seen tinges of light red in M42 in my 10", though mostly it is pale green. M8 was pale green or light gray for the most part. I don't recall red or pink in the Lagoon. But I did see light red/yellow in M27 and M57.

Mike

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I was observing M8 through a 30-inch Dob at an excellent site when I noted a hint of ruddiness. That one occasion has been the only time I've seen color in that particular object. I also noted an even fainter pink in the emission section of M20 that night.

On nights of exceptional transparency, through apertures of 14.5 inches and larger, I've seen blue surrounding the Trapezium, then green, a pinkish hue in M42's "wings", as well as something that resembles brown.

Dave Mitsky

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Chance favors the prepared mind.
De gustibus non est disputandum.

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As David said, the real key to discerning M57's central star is extremely steady seeing. High magnification is also essential.

As far as detecting colors in planetary nebulae is concerned, I've seen a few display color with my 101mm refractor but my best views have been through large aperture Dobsonians. The Blue Snowball Nebula, the Emerald Nebula, and the Cat's Eye Nebula show vivid colors when viewed through scopes of 25 inches and larger.

Dave Mitsky

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Yup, in a really big scope, the blue-green color can be stunning to say the least. One night many years ago at the Nebraska Star Party, I was using Tom Miller's 30 inch Obsession at very high power on the Cat's Eye. The color was such a vivid lime-green and the detail so stunning that I just about fell off the ladder! It looked like a low-resolution HST image of the nebula. After that, those of us who were present all got T-shirts with the HST image of NGC 6543 on them with the caption, "Here kitty, kitty kitty.." underneath . Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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"To be frank, up until a few years ago, I too was more than a little skeptical of the claims for seeing M57's central star in something as small as a 10 inch."

I couldn't have said it better, and to be frank I remain more than a little skeptical. However, I will keep trying and encouraging folks that I know and trust to keep trying, and as soon as I or one of them sees it I will join the ranks of the believers! However, it is a slippery slope and pretty soon folks start reporting observing it in their 4" apos from Central Park.

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It is fine to be skeptical concerning one's own chances of seeing the central star in a scope as "small" as a 10 inch. Not everyone will (or can) see it, as it is definitely a challenge. I do not frequently see it myself, although I do usually look for it on any halfway decent night. I remain skeptical of claims of central star sightings at moderate to low powers, as the glow in the middle of the nebula tends to create a "false central star" effect. However, at high power, it has been seen in scopes around 10 inches of aperture by some very experienced and well-known amateur astronomers, so the "claim" here is a perfectly valid one. Indeed, Steve O'Meara has seen it in the 9 inch refractor at Harvard (definitely a non-dark sky observing site). The techniques described earlier for hunting down the elusive M57 central star have already been described and have worked successfully for more than a few people under conditions of good to excellent seeing. However, linking this feat to things like averted imagination or certain other claims which are clearly ridiculous is probably not good form here. Such statements could be potentially insulting to those who have succeeded in sighting the central star. Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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Thanks David, the question mark I had in my notes about the central star in M 57 has been erased. I've looked at this object numerous times w/10" SCT (at dark sky site) and (per notes) I claimed to have seen a "flicker" of starlight in the center. I always figured it was due to looking at it for long intervals; that light retention factor, but then that type of light wouldn't "flicker/glimmer". Thus my notes will now state that I've been flashed by M57's central star. AND I do see color (green and yellow) in the ring.

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The star's behavior is rather irritating to say the least, but at least we know why it appears the way it does. On some nights, it never appears no matter how big the scope is due to seeing disturbances, while other times, it flashes on and off as if some sadistic alien is turning it on and off with a switch. I have seen it appear for anywhere from a fraction of a second to up to a minute, but usually, it tends to only be briefly visible when it is visible at all. It is just one of the many challenge objects which make amateur astronomy so much fun. Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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Great thread! Lots of good stuff here.

FWIW, I know NGC6572 as the "Blue Racquetball". I hadn't heard any of the other names before. Then again, given my eyes, I probably would have named it the "Gray Snowball".

Cheers,
-- Jeff.

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Are any planetaries nicknamed "The Gray Cottonball"? If not, I could suggest quite a few! (Actually, that might fit a lot of globulars better!)

Blue, green, gray--they're all fascinating to see, aren't they?

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Tim

Zhumell Z10 dob
Meade 60mm refractor
Zhumell 1.25" eyepiece and filter kit
Zhumell sky-glow, UHC, and OIII filters

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This is a most entertaining thread; it really has snowballed.

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He he... but the thread looks kind of a taupe/brown on my machine.

-- Jeff.

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Nikon 18x70s / UA Millennium                                       Colorado:
Solarscope SF70 / TV Pronto / AP400QMD                       Coronado SolarMax40 DS / Bogen 055+3130
APM MC1610 / Tak FC-100 / AP1200GTO                        Tak Mewlon 250 / AP600EGTO

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Ouch! I don't mean to ridicule your claim, I just don't believe it -

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It s really not over the top. Despite a slippery slope effect that winds down into the utter silly, this is an observation thats actually quite plausible. Let me explain...

I have no magic eyes. Merely a nice scope, at that time 6.2v skys [which just arent terrific, but merely deep sky doable] . I flat out hit a solid 15V at 240x. It wasnt a maybe - really, it was there. When you observe enough faint whatevers theres a reality check you get on wether its there or not. Fifteen V [visual magnitude not photo] is nice. It doesnt break any records, but Im happy i pulled it off.

Bumping up the aperture an inch and a quarter and using fairly high magnification, plus living out in the damned boonies [sorry dave] and coupled with the the subject revealing the nature of the seeing and its a pretty fairly plausible observation.

O'Mearas claim similarly done with the Harvard refractor is also plausible. Too, he's probably got better visual acuity on fine details - especially deep sky. Barbara Gordon is another one I've heard of whos got Santa Barbara instruments for eyes.

Where my baloney detector raises its head is in a claim I read regarding a 5" aperture for the central star. Thats just too too small no matter how perfect the faint star image for me to really feel comfortable accepting.

On deep sky limits though...

I'd suggest the following...

1.Fairly good seeing and super transparent skys like we get in the cooler months. Spft seeing isnt even worth the time.

2. Atleast 30 power per inch of aperture.

3. Know EXACTLY where to look.

4. This is critical - BREATHE. Breathe Breathe Breathe. Even light breath holding "for the moment" as you concentrate makes those stars just grain out and quick.
I used to just shrug on this as overhype and too obvious. That is until I was at the last five tenths of my mag limit.

Lastly: If you havent given a solid half hour at the ocular, you werent really at your limit. For me its more like 20 minutes, I'm rounding it off to 30.

One More Lastly: The day of the ob and maybe the day prior too - avoid bright lights. Use good dark sunglasses outside.

Having said all that - did it help me see the central star?

Oh hell no. Not a glimmer but I found my absolute limit for Sherman, Connecticut.

ITs totally plausible... the 5" refractor thing I read about ? No way. Simply profoundly NO. There are limits somewhere - I havent enough experience all the heck all over the darkest skys in the world, but that one is just too too far out there for me to rest even questionably on.

Pete

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One More Lastly: The day of the ob and maybe the day prior too - avoid bright lights. Use good dark sunglasses outside.

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I make it a point to ALWAYS wear my sunglass magnetic clip-ons over my prescription glasses whenever I go outdoors when the sun is up. I guess it helps, because I can see some pretty dim things both naked eye and through instruments. I wonder, though, if bright lights indoors also might hurt someone's dark adaptation for the next few days. It is ridiculous how bright most rooms are in most buildings nowadays. In my office building, any rooms I have any modicum of control over, I ask the maintenance people to unscrew about half the florescent lights (or I do it myself). And if you just open the shades and use the natural light to work at your desk, people ask, "Why are you working in the dark?" Philistines! Sometimes the indoor lighting literally hurts my eyes. It burns! It burns!

Mike

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Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!

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Jeff,

That's funny. It's light violet on mine!

Mike

In my experience, when a thread becomes mostly jokes, it is winding down. Let's see if anyone can give us fresh observations or insight on the colorful planetaries!

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If you want more, take a look at the thread on the Cat's Eye in this forum. I laughed out loud when after the second post in the thread mentioned the word "color," the same responses started coming discussing color sensitivity.

It was like deja vu all over again!

Sometimes reminds me of old Monty Python sketches and the way they used to argue things back and forth endlessly. Perhaps this is becoming another "dead parrot." (Now THERE was a lovely shade of blue!)

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Tim

Zhumell Z10 dob
Meade 60mm refractor
Zhumell 1.25" eyepiece and filter kit
Zhumell sky-glow, UHC, and OIII filters

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And if you just open the shades and use the natural light to work at your desk, people ask, "Why are you working in the dark?" Philistines! Sometimes the indoor lighting literally hurts my eyes. It burns! It burns!

Mike

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Yes, I hear you. Sometimes I think we are turning into vampires (with a better taste in beverages)!

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Tim

Zhumell Z10 dob
Meade 60mm refractor
Zhumell 1.25" eyepiece and filter kit
Zhumell sky-glow, UHC, and OIII filters

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Barbara Gordon is another one I've heard of whos got Santa Barbara instruments for eyes.

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In my experience, when a thread becomes mostly jokes, it is winding down. Let's see if anyone can give us fresh observations or insight on the colorful planetaries!

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Great suggestion.

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Tom (Pegster)
DSH-8 (GSO Dob)
15x70 Oberwerks
SVP/ED80
WO 66 Petzval
Sears Discoverer EQ 60/900
8x42 Regals




History is Philosophy teaching by examples.
Thucydides

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It s really not over the top. Despite a slippery slope effect that winds down into the utter silly, this is an observation thats actually quite plausible. Let me explain...

I have no magic eyes. Merely a nice scope, at that time 6.2v skys [which just arent terrific, but merely deep sky doable] . I flat out hit a solid 15V at 240x. It wasnt a maybe - really, it was there. When you observe enough faint whatevers theres a reality check you get on wether its there or not. Fifteen V [visual magnitude not photo] is nice. It doesnt break any records, but Im happy i pulled it off.

Bumping up the aperture an inch and a quarter and using fairly high magnification, plus living out in the damned boonies [sorry dave] and coupled with the the subject revealing the nature of the seeing and its a pretty fairly plausible observation.

O'Mearas claim similarly done with the Harvard refractor is also plausible. Too, he's probably got better visual acuity on fine details - especially deep sky. Barbara Gordon is another one I've heard of whos got Santa Barbara instruments for eyes.

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Yes, it was Barbara Wilson who is the one with the "eagle eyes". As for you and your scope (8 inches aperture I think), you are doing pretty darn well to get down to magnitude 15. Now, what I will tell you is that you probably won't see the central star in M57 with an 8 inch, but I will *not* tell you that you *can't ever* see it. You are close enough to the magnitude threshold and there is enough variability in the factors involved that one night, you might just succeed. You should keep on looking (at least until you get tired of trying). There are a few reports of the star being seen in an 8 inch at very high power, so we can't necessarily rule out the possibility of you seeing the star, even though you probably won't. I had all but ruled-out M57's central star in my 9.25 inch SCT when I was taken completely by surprise when it popped-up in my 9.25 inch. I had looked for quite a while before in the 9.25, but had only seen the star in my old 10 inch Newtonian (and even then, I had only seen it once or twice a year at most). If I hadn't left my 5-8mm Speers Waler in the NexStar by accident during a slew, I never would have had the pleasure of being blown off the stool by seeing the star (and from my front driveway no less). It didn't stick around long, but it was there from the moment I looked in, so I just sat there in stunned silence almost not believing my eyes. I really truly hope that one day, you get that same kind of surprise. Clear skies to you.

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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org

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If I hadn't left my 5-8mm Speers Waler in the NexStar by accident during a slew, I never would have had the pleasure of being blown off the stool by seeing the star (and from my front driveway no less).

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It's interesting what limits you can set for yourself strictly by assumption, even when you aren't aware you've made them. I don't think I ever given the central star a thought - I just wipe it off my slate and figure its in the realm of 12 1/2" scopes and up. I don't, or didn't consciously say that or think it, but its a subconscious assumption - don't even bother. I read somewhere its this and that and so forget it. Then by serendipity you scan across it with the proper set up an there you go.

Ive enjoyed high power views of M57 that probably broke some amateur astronomy "law" on whats acceptable or useful enlargement. But, it was always in the interest of seeing more detail in the ring -the star was a total write off.

I still think it is for me - atleast in Connecticut, however there is a place in Colebrook Connecticut, so dark, even Alan MacRobert from Boston has attended it in the past. Giving it a shot there might be a nice idea though its in the fall by that point - might be impossible.

It'll be a secret if I try it tho at a party. And if I succeeded - just given some sampling on this thread - who the hell would believe me?

Its still a write off for me - but it is cool knowing I am ALMOST - just ALMOST - able to. If it were only visible in a 16" aperture, it wouldnt have the same appeal.

Thanks for the compliment on my mag-bag!

Pete

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