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asaint
Carpal Tunnel
Reged: 04/25/03
Posts: 2019
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What's Up Vulpecula
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proud uncle
Pooh-Bah
Reged: 01/22/07
Posts: 1329
Loc: Central Texas
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Steve, another great article! I am familiar with M27 and Cr399. I will need to hunt down the two OCs. Friday night CSC looks excellent (transparency 5/5, seeing 4/5) for that search.
It's also been awhile since looking at M27. The interesting thing with M27 is the longer I look at it, the image I see varies between the circular and the hourglass/dumbbell shape. It sounds from your article I would need a larger than 10" scope to see the central star? As I recall, sometime I read (I can't remember the source) that M27 and M57 have the same basic torus shape. With M57 we are looking face-on, hence the ring shape. With M27 we are looking more edge-on. Does that sound correct? Since M27 has larger apparent size, is it closer? Are the actual sizes of these PN close to the same?
You gave star counts wrt the open clusters. With a loose OC like CR 399, which is in a rich Milky Way star field, how do I know which stars are in the cluster? Obviously, CR 399 has many more stars than just the familiar coat hanger asterism.
Thanks, again, for another great informative article.
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Kenneth
Zhumell 10" Dobsonian (f/4.9)
2" 32mm WA eyepiece
9mm, 12.5mm, and 20mm Plossls
6mm TMB/BO Planetary
2" 2x ED Barlow
Nikon 10x50 binocular (6.5 deg FOV)
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NerfMonkey
super member
Reged: 06/12/08
Posts: 184
Loc: NE Ohio
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Quote:
Obviously, CR 399 has many more stars than just the familiar coat hanger asterism.
I've always been under the impression that Cr 399 only includes the Coathanger and is actually just an asterism, not an actual cluster. Same with Mel 111 in Coma Berenices.
But I could be wrong; I'm not particular about distinguishing field stars from cluster stars when viewing open clusters anyway.
Excellent article. I've looked for 6802 numerous times but always underestimate how small it is. I'll give it another shot next clear night.
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Mike
71 Messiers
149 total DSOs
6 planets
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WadeVC
Carpal Tunnel
Reged: 12/02/05
Posts: 2776
Loc: Lodi, California,
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Steve,
As usual, a very informative and well written article that offers observers a few new (or forgotten about) DSO's.
Nicely done.
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Orion XTi10 f/4.7
Orion XTi8 f/5.9
Meade NGC 70mm f/10
Orion UltraView 10x50 Wide-Angle Binoculars
My Sketch Gallery
My Astronomy Blog
A wise man can see more from the bottom of a well than a fool can from a mountain top.
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stevecoe
Reged: 04/24/04
Posts: 2114
Loc: Arizona, USA
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Wade and Mike...thank you, it is always gratifying to hear from happy "customers". Let me know what you see in some of these objects, or post to the deep sky forum.
Kenneth, as far as numbers of stars in clusters, I guess as best I can where the edge of cluster exists. It is a mediocre method, but I don't have any other. If I look at the data beforehand for that cluster, I can know the size in the field of view of the eyepiece I am using and estimate the cluster size from that. The star count is just trying to give me a feel for how many stars I resolved within that cluster.
Clear skies to us all;
Steve Coe
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150mm 6" f/8 Celestron Refractor on Sirius Mount
80mmED 3" f/7.5 Orion Refractor
Author "Deep Sky Observing" Springer-Verlag
Author "Nebulae and How to Observe Them" Springer
New Canon Xt astrocamera with Hutech modification
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Digital Don
scholastic sledgehammer
Reged: 01/20/04
Posts: 862
Loc: Manteno
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I've always called NGC-6802 the "Lint Nebula" because of it's appearance, and proximity to the "Coathanger". It reminds me of a piece of cosmic lint!
Heck, they can see scorpions, flying horses, or eagles in the sky... why not lint! 
Don 
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NerfMonkey
super member
Reged: 06/12/08
Posts: 184
Loc: NE Ohio
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I found 6802 for the first time last night at BFSP. Didn't resolve any stars because I was too busy going back to old favorites and just staring up at the sky. Now that I know where it is I'll try resolving it some time.
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Mike
71 Messiers
149 total DSOs
6 planets
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stevecoe
Reged: 04/24/04
Posts: 2114
Loc: Arizona, USA
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Mike;
I understand completely the "just staring up at the sky" part of your observations. My observing buddy and I have chuckled for years at the fact that we haul all this equipment out to dark skies and then sit in the comfy folding chairs and ooogle the sky. Lots of fun.
Clear skies to us all;
Steve Coe
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150mm 6" f/8 Celestron Refractor on Sirius Mount
80mmED 3" f/7.5 Orion Refractor
Author "Deep Sky Observing" Springer-Verlag
Author "Nebulae and How to Observe Them" Springer
New Canon Xt astrocamera with Hutech modification
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RussL
Music Maker
Reged: 03/18/08
Posts: 1573
Loc: Cayce, SC
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Just found the Coathanger by accident recently. Reminds me of Mel 111 except that I can get it all in my field of view at 16x. I understand that it isn't a true cluster in that the stars are all unrelated. Very nice to look at. 
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--Russell
"Akita mani yo." Observe everything as you walk. (--Lakota)
Celestron Celestar 8 Standard SCT, f10
Celestron 80mm Wide View ref., f5
Criterion RV-6 Dynascope, Newt., f8, (c. 1962)
Sears Discoverer 60mm ref., f7, (c. 1973)
Celestron Ultima DX 10x50, 6.5 TFOV
Tasco 7x35 wide
Several mediocre eyepieces
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proud uncle
Pooh-Bah
Reged: 01/22/07
Posts: 1329
Loc: Central Texas
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Quote:
I will need to hunt down the two OCs. Friday night CSC looks excellent (transparency 5/5, seeing 4/5) for that search.
I found 6802 at the east end of the Coathanger. As Steve described, it was faint, only resolving a handful of stars. But the mottling of the faint glow indicated the presence of many more stars I was not quite resolving as individual points of light.
I think I found 6940. It was much easier to see than 6802 but more difficult to find by starhopping because of a lack of really bright reference stars in the immediate area. But I found what appeared to be an OC with lots of relatively bright stars. Both were great finds.
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Kenneth
Zhumell 10" Dobsonian (f/4.9)
2" 32mm WA eyepiece
9mm, 12.5mm, and 20mm Plossls
6mm TMB/BO Planetary
2" 2x ED Barlow
Nikon 10x50 binocular (6.5 deg FOV)
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stevecoe
Reged: 04/24/04
Posts: 2114
Loc: Arizona, USA
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Kenneth;
Sounds like two good observations, I think NGC 6940 is in front of the "Dark Rift" in the Milky Way, so that dust cloud is blocking off the distant stars and as you said there are few to use for star hopping.
Clear skies to us all;
Steve Coe
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150mm 6" f/8 Celestron Refractor on Sirius Mount
80mmED 3" f/7.5 Orion Refractor
Author "Deep Sky Observing" Springer-Verlag
Author "Nebulae and How to Observe Them" Springer
New Canon Xt astrocamera with Hutech modification
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