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Old 27-09-2011, 08:58 PM
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Paddy (Patrick)
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Some things in Scutum, Sagittarius and Aquila 25/9/11

Sunday night was considerably kinder than Saturday, only limitation was the need to go to work the next day. Thought it was time to hunt down Palomar 11 and I hopped via a few other interesting sights along the way. Here are the notes.

Telescope 410mm (16”) f4.9 tri-dob reflector
Eyepieces 28mm UWAN, 17,13,9 mm Naglers, Paracorr
Navigation: Night Sky Observer’s Guide (NSOG), Uranometria

2100

Seeing very good, transparency fair-poor (dust lanes of Milky Way visible but not clear or dark)

NGC 6705/Messier 11 OC in Scutum “Wild Duck” cluster

135X A gorgeous OC that looks very like a globular. Many stars of similar magnitude and colour apart from one which is much brighter. Looks about 15’ across. Quite striking are the patterns of stars and dark spaces within a marked block shape which comprises the bulk of the cluster. It looks a bit like an impression of a wood cut of Chinese calligraphy. I can’t really see the “Wild Duck” shape. An intriguing knot of stars is close to the lucida.

NGC 6712 GC in Scutum

175X A soft and somewhat irregular GC, there is a broad faint 7’ outer halo and a brighter 5’ inner one, the western edge of which appears somewhat pointed. There is a small dark space in the eastern edge of the inner section and following the GC itself a star poor area of sky which might be an intervening dark nebula responsible for the unusual features of the GC. A small dark line runs across the halos SE part from the eastern to the southern edge. There are quite a few faint resolvable stars.

NGC 6822 Barnard’s Galaxy in Sagittarius

175X Although challenging with the poor transparency, the galaxy is discernible. A line 3 foreground stars runs E-W at the southern end of the galaxy which is a 7’x3’ N-S glow from the centre of the line. Better at 175X than at 135X. No detail discernible.

NGC 6818 PN in Sagittarius “Little Gem”

250X A distinct bright bluish disc, softer at the western edge, no central star. Maybe an impression of a tiny dark patch in the centre, but far from convincing. No structure observed. Looks about 30” across. Bright and blue with UHC and OIII filters, but no further details apparent.

Palomar 11 GC in Aquila

175X Quite faint for a mag 9.8 GC. Close to bright foreground star at NW edge, to the east is a convex east arc of stars. To the west is a line of stars which is the base of a triangular asterism. Boxed in by these asterisms is a faint 7’ circular glow, which is the GC. There is a faint soft core with no resolved stars. Would be easily overlooked.

Spent some time with 47 Tuc and NGC 253 for some visual splendour before retiring.
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Old 28-09-2011, 06:24 AM
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Another great report Paddy,despite the viewing conditions

M11 is a nice cluster,Countless stars,The wedge shape you mention I think is the so described flock of birds.Thats why its called the wild duck cluster.

Ngc 6818 sounds interesting I might give it a try soon.

Great to see you enjoying yourself under the stars even if the conditions are poor.

regards
Orestis
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Old 01-10-2011, 04:47 PM
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madbadgalaxyman (Robert)
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As mentioned in another thread, the total stellar mass of Messier 11 is well within the range of masses occupied by our Galaxy's globular clusters.

I am sorry that say that I never ever see wild ducks, mythological figures, or any other fanciful thing in the sky. All I see is geometric shapes! (no imagination?)

Last edited by madbadgalaxyman; 01-10-2011 at 04:50 PM. Reason: addition
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Old 01-10-2011, 08:18 PM
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Gem (Grant)
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Too much latin at school... your title makes me visualise some Roman archer standing next to a legionary standard...

Mea culpa: I need to get out more...
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Old 03-10-2011, 04:49 PM
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Thanks gentlemen! Robert, I suspect that the lack of "imagination" or the ability to not get infected by other people's imaginative memes is probable a great asset for accurate observing! Grant, I was fortunately spared Latin at school. Hope I don't meet the pedantic centurions from "Life of Brian"
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Old 14-10-2011, 11:48 AM
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I like how you mixed up one challenging object (Palomar 11) with 3 eye candy objects. That's usually how I observe also, though the proportions are usually reserved.

If you try Palomar 11 again on a night of good seeing and pump up the magnification, you should be able to resolve some of the cluster's stars, which appear starting at mag 15.5 or so.

Here's one of my observations from back in 2004 (with my 18")

At 225x, appears faint, round, ~3'-3.5' diameter with almost no central brightening although the globular fades around the periphery. Several faint stars are superimposed. It was difficult to estimate the size as the halo is not well defined. At times I felt the diameter was as large as 6' but sometimes only appeared 3' at best. At 435x, a half dozen faint stars are superimposed. The cluster's surface brightness is quite low at the magnification, though.
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Old 15-10-2011, 11:15 AM
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Quote:
Originally Posted by Paddy View Post
NGC 6705/Messier 11 OC in Scutum “Wild Duck” cluster

135X A gorgeous OC that looks very like a globular. Many stars of similar magnitude and colour apart from one which is much brighter. Looks about 15’ across. Quite striking are the patterns of stars and dark spaces within a marked block shape which comprises the bulk of the cluster. It looks a bit like an impression of a wood cut of Chinese calligraphy. I can’t really see the “Wild Duck” shape. An intriguing knot of stars is close to the lucida.
M11 is a great cluster. Thousands of stars. I agree with you about it looking rather like a globular cluster, especially in binoculars. The "Wild Duck" shape is derived from the cluster's squared off look, giving the impression of a large number of ducks flying in formation.

Regards, Rob
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Old 15-10-2011, 02:48 PM
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Paddy (Patrick)
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Quote:
Originally Posted by SteveG View Post
I like how you mixed up one challenging object (Palomar 11) with 3 eye candy objects. That's usually how I observe also, though the proportions are usually reserved.

If you try Palomar 11 again on a night of good seeing and pump up the magnification, you should be able to resolve some of the cluster's stars, which appear starting at mag 15.5 or so.

Here's one of my observations from back in 2004 (with my 18")

At 225x, appears faint, round, ~3'-3.5' diameter with almost no central brightening although the globular fades around the periphery. Several faint stars are superimposed. It was difficult to estimate the size as the halo is not well defined. At times I felt the diameter was as large as 6' but sometimes only appeared 3' at best. At 435x, a half dozen faint stars are superimposed. The cluster's surface brightness is quite low at the magnification, though.
Thanks Steve, I'll go back on a better night - when La Nina finishes I suspect - and have another look. I find the ratio challenging/eye candy
varies inversely with the frustration of the viewing conditions.


Quote:
Originally Posted by Robh View Post
M11 is a great cluster. Thousands of stars. I agree with you about it looking rather like a globular cluster, especially in binoculars. The "Wild Duck" shape is derived from the cluster's squared off look, giving the impression of a large number of ducks flying in formation.

Regards, Rob
Thanks Rob - have to go back with this in mind.
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Old 17-10-2011, 02:24 PM
SteveG (Steve)
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Did you notice how I slyly reversed the letters "s" and "v" in reversed? Yeah, that's what happened.

Steve
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Old 17-10-2011, 07:38 PM
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Paddy (Patrick)
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Did you notice how I slyly reversed the letters "s" and "v" in reversed? Yeah, that's what happened.

Steve
Very subtle!
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