TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

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TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

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Post by kt4hx »


After some time off due to other requirements on my time, I am bringing back the TSS Monthly DSO Challenge. However, I am changing the format to a bi-monthly effort. Because the English language is a bit screwy at times, the term “bi-monthly” can mean either twice monthly or once every other month. In this case, my intent is the latter rather than the former. This will give me more time to prepare each article and you more time to complete the challenge as you have to deal with the variables of your local conditions and individual demands on free time.

Those of you who know me even modestly know well that I am a hardcore galaxy hunter. However, what some may not know is that I really, really like globular clusters almost as much. Therefore this challenge will present a triple-play globular event, which will highlight only one constellation in each celestial hemisphere. Each of those constellations contain three primary globular clusters, which all appear in the New General Catalogue, and in the case of the northern entry, two also appear in the Messier catalogue. For the northern folks we will feature the constellation of Hercules, and for our southern friends the constellation Ara. The data for each object is sourced from Telescopius.com, and this includes visual magnitude, angular size (in arc minutes), surface brightness (in mag per arcmin2) and the core concentration class from the Shapley-Sawyer scale (1-densest thru 12-loosest). Without further ado, let’s reveal what objects I have for you to pursue over the July/August timeframe, and I wish you all good luck with your observing, sketching and imaging pursuits. As always I encourage you to post your results here so that all, including you, may learn from your experience.


Northern Celestial Hemisphere – Hercules, the mythological hero and strongman:

Messier 13 / NGC 6205 (globular cluster, mag=5.8, size=20.0’, SBr=12.0, class=5):
Known famously as Great Globular Cluster in Hercules or the Hercules Globular Cluster, the 13th entry in Charles Messier’s Catalogue of Nebulae and Star Clusters published in 1784 is well known to the vast majority of amateur astronomers with even a modicum of experience. It was actually discovered by Edmond Halley 1714 and independently discovered by Charles Messier in 1764. Often the very first globular observed by beginning observers, it can be glimpsed naked eye under excellent and dark conditions, and is readily apparent as a non-stellar object with minimal optical aid. Sporting a very bright and compact core, it blazes into glory in even smaller scopes, where it is possible to resolve some stars in its outer fringes. As aperture increases, one can resolve more stars across its face all with its intensely bright and compact core as a backdrop. Not only is it a prominent visual target, but it is also very easy to locate. It is situated along the western side of the most prominent portion of Hercules, the famous “keystone” asterism about one-third of the way along a line from mag 3.5 Eta to 2.8 Zeta Herculis. With increasing aperture more and more stars become resolved, and one can glimpse strings of stars emanating outward from the core into the outer halo.

A real challenge with this object is the visual detection of a structural detail known as the “propeller.” This is a small and very dim three-pronged feature emanating from a common center point that gives the impression of a propeller. It is caused by intervening dust within the cluster. This elusive detail is easier to discern using imaging than via visual observation, but it can be seen with great care using larger apertures under a steady dark sky. If you don’t feel quite up to the “propeller” challenge, but still feel sporty, there is a nearby galaxy you can try. NGC 6207 is a spiral galaxy glowing at magnitude 11.6 that is only 27.5’ northeast of the center of M13. Spend some time with M13 and you will see just why so many observers return to it year after year.

Messier 92 / NGC 6341 (globular cluster, mag=6.3 size=14.0’, SBr=12.0, class=4):
This globular cluster is often thought of as M13’s little brother. Though it does appear similar to the more famous globular, it is smaller and about half a magnitude dimmer with a subtly more condensed core. It is located in northern Hercules about 6° 20’ north of the northeastern corner star of the keystone asterism, mag 3.2 Pi Herculis. Discovered in 1777 by Johann Bode, it was independently discovered by Charles Messier in 1781.

Visually in it can be located with binoculars and small apertures as a small glowing orb. Even in moderate aperture, it begins to reveal some resolution at its fringes and across its face. In larger aperture the resolution becomes deeper into its body with some of the outer portions of the core starting to resolve. It is a beautiful object on its own, and while it is not as often observed as is M13, it truly does not play second fiddle. It reveals several strands of stars flowing outward from the core and displays noticeable resolution of its members, so while it is smaller and slightly dimmer, it truly does hold it own visually against its more famous neighbor. If one does return to M13 year after year, they would depriving themselves of something equally as beautiful if they did not revisit M92 at the same time.

NGC 6229 (globular cluster, mag=9.4, size=4.5’, SBr=12.4, class=4):
The third globular cluster in Hercules that we find in the New General Catalogue was discovered by William Herschel in 1787. This small and fairly dim cluster is most definitely lesser known to many observers and imagers. Its weak visual appearance makes it much more of a challenge for smaller apertures, though it may be glimpsed as a very small fuzzy star-like object. Even it moderate to larger apertures it does not yield much in terms of resolution.

Located nearly 5° ENE of mag 3.9 Tau Herculis, it forms a triangle with a widely spaced pair of 8th magnitude field stars (HD 151651 and HD 151689) to its west. It’s very small and compact core is noticeably bright within a small and dim halo. Depending upon aperture it may take on a mottled appearance, hinting that one is near some level of stellar resolution, but it takes larger aperture to pick out a very modest number of member stars at best. It is not showy in any form of the word, and certainly gets lost in the rush to observe M13 and then M92. But, it certainly is worth hunting down and taking a peek so that one can claim to have observed the Hercules trio of globular clusters.


Southern Celestial Hemisphere – Ara, the mythological altar of Zeus:

NGC 6397 (globular cluster, mag=5.3, size=31.0’, SBr=12.5, class=9):
Moving south of Scorpius we come to the constellation of Ara. The brightest globular of the three within the celestial altar is this large and showy cluster. It was discovered in the 1751-1752 timeframe by Nicolas-Louis de Lacaille using his ½ inch 8x telescope while surveying the southern skies from South Africa. This cluster lies at about 7.8 KLY distance from us, making it the second closest globular to the Earth.

Depending upon one’s sky quality it can be easily glimpsed with the naked eye at best, or at a minimum with binoculars and small aperture scopes. In medium to large scopes it is a sight to behold, revealing many curving streamers of stars emanating outward from it with many stars resolved at its fringes and across the face. It contains a smaller bright core and one may see some some resolution at the edges of this core as well as some mottling in the core itself, all forming a backdrop for the resolved stars across the cluster’s face. This is a beautiful globular that if located farther north in the sky would rival the best we have in the northern hemisphere without a doubt. Look for this delightful cluster about 55’ NNE of mag 5.2 Pi Arae, it is difficult to miss!

NGC 6352 (globular cluster, mag=7.8, size=9.3;, SBr=12.3, class=11):
Our next cluster in Ara is located in the north central part of the constellation about 1° 47’ northwest of mag 2.9 Alpha Arae.. The mag 7.0 star HD 157555 is just 14.5’ southeast of the cluster in the direction of Alpha Arae. This cluster was discovered by James Dunlop in 1826 during his survey of the southern skies from Paramatta, New South Wales, Australia.

Visually it should not be difficult in binoculars or small apertures. Medium aperture will begin to show some resolution and display its loose central area with a very small modestly concentrated core. Larger aperture will reveal more and deeper resolution of both its halo and central region with its small core as a backdrop. Not as large or showy as NGC 6392, it still holds its own visually and is a beautiful cluster in its own right.

NGC 6362 (globular cluster, mag=8.1, size=15.0’, SBr=13.7, class=10):
Our final globular in Ara and for this month’s challenge is found in deep southern Ara close to the border with Apus. It can be found about 1° 12’ northeast of mag 4.8 Zeta Apodis, situated within a box of four field stars (mags 6th to 9th). This cluster was also discovered in 1826 by James Dunlop during his time at Paramatta.

Another target accessible to binoculars and small apertures, it starts to reveal its true nature more with moderately sized scopes. It contains a loosely structured broadly concentrated central region with a bit of an uneven halo structure. Resolution of many stars is possible with moderate and particularly larger aperture, and one may glimpse a rambling line of stars crossing the face of the cluster. Visually it is a bit more uneven than are the two previous globulars, but it is no less beautiful and will not disappoint.


I now leave the above objects in your hands to pursue over the next two months. Obviously given the declinations involved, not everyone would be able to observe all of these objects. But should you be lucky enough to live at a more southerly latitude in the northern hemisphere or a more northern latitude in the southern hemisphere and have access to all of them, or at least a portion of the opposite hemisphere’s objects, please feel free to observe any that you have access to. Again, I encourage you to post your results here. Whether your game be visual observation, sketching or imaging, we would like to see just what you can come up with for any of the above objects that grace your night sky. So good luck and enjoy the fun of the challenge. :)
Alan

Astro Sky 17.5 f/4.5 Dob || Apertura AD12 f/5 Dob || Zhumell Z10 f/4.9 Dob
ES AR127 f/6.5 & ED80 f/6 on Twilight-II || Apertura 6" f/5 Newtonian on Twilight-I
TV Ethos 100° 21mm, 13mm || ES 82° 24mm, 18mm || Vixen LVW 65° 22mm
Pentax XW 70° 10mm, 7mm, 5mm || barlows
DGM NPB Filter || Orion Ultra Block, O-III and Sky Glow Filters || Baader HaB Filter
Primary Field Atlases: Interstellarum and Uranometria All-Sky Edition
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"Astronomers, we look into the past to see our future." (me)
"Seeing is in some respect an art, which must be learnt." (William Herschel)
"What we know is a drop, what we don't know is an ocean." (Sir Isaac Newton)
"The eternal silence of these infinite spaces frightens me...." (Blaise Pascal)
"No good deed goes unpunished." (various)
"I have become comfortably numb." (Roger Waters)
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TSS DSO Challenge - my observations

#2

Post by kt4hx »


Below are some of my observing notes for the objects highlighted in the July/August TSS DSO Challenge. I have observed the northern targets (in Hercules) multiple times over the years, and selected a sample of for each of them from my logs. Now with regard to the southern objects (in Ara) they were only observed while on a business trip farther south where I only had access to much less aperture (what I could take with me). But see them I did, and I have posted those results as well. I hope you all get out there when possible and take a look at those that you have access to and post your findings. Good luck!


Messier 13 / NGC 6205 (Hercules, globular cluster, mag=5.8, size=20.0’, SBr=12.0, class=5):
The below observation is from April 2021 at our dark site house using the 17.5 inch dob that is permanently located at that location.

I easily spotted the cluster in the 8x50 RACI finder then moved to the eyepiece where I was greeted with my first view for 2021. Large and bright at 94x, it was bejeweled with uncountable stars. The outer halo was well resolved as were myriad stars across the face of the disk. The globular had a three dimensional appearance with the resolved stars across its face underpinned by the denser central portion of its body with the smaller tight blazing core as the final layer beneath. There were very apparent multiple curving streamers of stars emanating from the central structure outward giving it a bit of a starfish-like appearance. Much less apparent and only subtly seen was portions of the dark lanes forming the “propeller” feature just southeast of the core. Viewed briefly at 152x the cluster was blindingly bright and with the variations in seeing it appeared like a shimmering pool of stellar points overlaying the unresolved dense center. I have never known this object to disappoint visually, and this evening it was in stunning form.

The below observations for M92 and NGC 6339 are from nine years ago. They were made from our backyard using the 12 inch dob. At that time our skies were a solid Bortle 5 quality, but have since degraded to a Bortle 6 on average as the slow light creep around us continued.

Messier 92 / NGC 6341 (Hercules, globular cluster, mag=6.3, size=14.0’, SBr=12.0, class=4):
Aiming the scope at the wide pair of Pi and 69 Herculis, I then star hopped just over 6° to their north. The cluster was easily visible in the 8x50 RACI finder scope. At 69x it appeared small but very bright and round in shape. It displayed good resolution of the outer regions as well as some across its face as magnification was increased to 89x, 114x and finally 142x. Some pretty lines and arcs of stars radiating out from the main body were easily seen. While not quite the match of M13, it certainly holds its own in the eyepiece.

NGC 6229 (Hercules, globular cluster, mag=9.4, size=4.5’, SBr=12.4, class=4):
Lying almost 7° northwest of M92 is magnitude 9.4 NGC 6229. With a smaller angular size of about 4.5’ this class 4 globular is definitely the weakest of the Herculean trio. It forms a triangle with two 8th magnitude stars, and at 69x it was small, but displayed a fairly bright center within a dimmer outer halo. Increasing magnification through the steps of 89x, 114x and 142x brightened the core, but no resolution was seen.


I observed the three southern globulars for this TSS DSO challenge from a suburban location that was just south of the equator back in early June 2016 while on a business trip. The sky quality was about Bortle 5 on average and the scope utilized was my Explore Scientific ED-80 refractor mounted on a Slik Pro-700DX tripod. The eyepieces in use at the time were ES 82° series 18mm, 14mm, 11mm, 8.8mm and 6.7mm. Here are my visual impressions of these objects.

NGC 6397 (Ara, globular cluster, mag=5.3, size=31.0’, SBr=12.5, class=9):
Easily spotting the triangle of mag 3.1 Zeta, 3.3 Gamma and 2.8 Beta Arae, I aimed the 80mm at Beta. Sweeping to the northeast, I tripped over a bright and large ball of light about 3° away. Even at 27x its core was pretty bright and I noted a couple of dim stars nearby. Viewing with 43x I picked up several little diamonds in an arc around its edge from the south to east as if trying to corral the big ball. When using 54x I got an impression that the globular was slightly elongated rather than purely round. This however may have been the result of the stars along the southeastern side that drew the eye in their direction. At 71x the globular became slightly granular in texture, especially with averted vision. Despite only being about 15° in elevation, down in the marine layer and with a constant wind causing some vibrations, it was quite a nice visual treat.

NGC 6352 (Ara, globular cluster, mag=7.8, size=9.3, SBr=12.3, class=11):
Aiming the scope at mag 2.9 Alpha Arae I could just fit it and mag 5.3 Iota and into the field of view of the 18mm (27x). Not quite halfway from Iota to Alpha I was suspecting a very soft glow, but it was quite fleeting. At 34x, my suspicions were confirmed and at 43x I was looking at a somewhat large but subtle round glow. Going ahead up to 54x and 71x, though it was still a bit subtle in nature, it was also quite apparent. Overall it appeared mostly homogeneous though it did seem to exhibit some very slight central brightening.

NGC 6362 (Ara, globular cluster, mag=8.1, size=15.0’, SBr=13.7, class=10):
With the naked eye I followed the gentle curve of Alpha, Beta, Gamma and Delta Arae to the SSE and spotted Eta Pavonis (mag 3.6). I aimed the scope at this star and swept about 2° to the southwest to a triangle of 7th magnitude stars. My quarry lay along the triangle’s southern side. Using 27x I noted a very subtle small round glow southeast of the westernmost star in the triangle. It was easier with averted vision. Going ahead up to 54x I seemed to detect a very subtle uptick in brightness in the central area, but overall it was mostly homogenous. Using 71x, I had the same sense of even illumination, though at times as seeing changed, there may have been that subtle increase in central brightness. No resolution of course in this sky with this aperture.
Alan

Astro Sky 17.5 f/4.5 Dob || Apertura AD12 f/5 Dob || Zhumell Z10 f/4.9 Dob
ES AR127 f/6.5 & ED80 f/6 on Twilight-II || Apertura 6" f/5 Newtonian on Twilight-I
TV Ethos 100° 21mm, 13mm || ES 82° 24mm, 18mm || Vixen LVW 65° 22mm
Pentax XW 70° 10mm, 7mm, 5mm || barlows
DGM NPB Filter || Orion Ultra Block, O-III and Sky Glow Filters || Baader HaB Filter
Primary Field Atlases: Interstellarum and Uranometria All-Sky Edition
---------------------------------------------------------------------------
"Astronomers, we look into the past to see our future." (me)
"Seeing is in some respect an art, which must be learnt." (William Herschel)
"What we know is a drop, what we don't know is an ocean." (Sir Isaac Newton)
"The eternal silence of these infinite spaces frightens me...." (Blaise Pascal)
"No good deed goes unpunished." (various)
"I have become comfortably numb." (Roger Waters)
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Re: TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

#3

Post by helicon »


Some nice globular targets Alan. M13 never fails to impress. I've also seen NGC 6207 a few times, but it's not always visible. I also enjoy NGC 6229, a cluster that most folks miss given the preference for the M92 and M13 showpieces.
-Michael
Dobsonian: 10" Zhumell f/4.9
Refractors: ES AR152 f/6.5 Achromat on Twilight II, KOWA 90mm spotting scope
Grab-n-go: AWB 5.1" Onesky Newtonian
Binoculars: Oberwerk 25x100, Celestron SkyMaster 15x70, Bushnell 10x50
Eyepieces: Explore Scientific line, GSO Superview, 9mm Plossl, Edmund 28mm RKE
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Re: TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

#4

Post by kt4hx »


helicon wrote: Thu Jul 14, 2022 12:56 pm Some nice globular targets Alan. M13 never fails to impress. I've also seen NGC 6207 a few times, but it's not always visible. I also enjoy NGC 6229, a cluster that most folks miss given the preference for the M92 and M13 showpieces.

Thank you Michael. When observing M13 from home, I liked to use nearby NGC 6207 as a benchmark object for gauging conditions, predominantly transparency. Indeed if conditions were poor it would either be a threshold object or not visible at all. Some observers simply miss NGC 6207 even when it is visible simply because they become so fixated on M13 that they don't really look around its periphery for other possible objects. NGC 6229 is indeed a curious object, and frequently overlooked. With two very bright Messier globulars in Hercules which draw observer's attention, it sits off to the side in obscurity, which is unfortunate. :)
Alan

Astro Sky 17.5 f/4.5 Dob || Apertura AD12 f/5 Dob || Zhumell Z10 f/4.9 Dob
ES AR127 f/6.5 & ED80 f/6 on Twilight-II || Apertura 6" f/5 Newtonian on Twilight-I
TV Ethos 100° 21mm, 13mm || ES 82° 24mm, 18mm || Vixen LVW 65° 22mm
Pentax XW 70° 10mm, 7mm, 5mm || barlows
DGM NPB Filter || Orion Ultra Block, O-III and Sky Glow Filters || Baader HaB Filter
Primary Field Atlases: Interstellarum and Uranometria All-Sky Edition
---------------------------------------------------------------------------
"Astronomers, we look into the past to see our future." (me)
"Seeing is in some respect an art, which must be learnt." (William Herschel)
"What we know is a drop, what we don't know is an ocean." (Sir Isaac Newton)
"The eternal silence of these infinite spaces frightens me...." (Blaise Pascal)
"No good deed goes unpunished." (various)
"I have become comfortably numb." (Roger Waters)
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Re: TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

#5

Post by sdbodin »


OK, something to do with the bright moon and my extended summer twilight. Actually fun putting together a composite comparison to the trio of globs. Quite a noticeable different, to say the least! All exposures similar; M13 25 minutes total in 1 minute subs, M92 19 minutes total in one minute subs, and NGC6229 28 minutes total in two minute subs. All composited to the same scale but most are edge cropped then plopped on a black canvas.
her_gc_comp.jpg
Specifics; Meade 16 LX200 at f6.2 with Starizona reducer, Atik 460ex mono camera at -5C. Guided with Meade 107D 4 inch SCT and Qhy5L-II mono. Captured and stacked in Nebulosity, final in PS CS5, posted image about 46% full size to meet forum rules.

Clear skies,
Steve
Scopes; Meade 16 LX200, AT80LE, plus bunch just sitting around gathering dust
Cameras; Atik 460ex mono, Zwo ASI1600MC-cool, QHY5L-II color and mono
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Re: TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

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Post by kt4hx »


sdbodin wrote: Sat Jul 16, 2022 11:21 pm OK, something to do with the bright moon and my extended summer twilight. Actually fun putting together a composite comparison to the trio of globs. Quite a noticeable different, to say the least! All exposures similar; M13 25 minutes total in 1 minute subs, M92 19 minutes total in one minute subs, and NGC6229 28 minutes total in two minute subs. All composited to the same scale but most are edge cropped then plopped on a black canvas.

her_gc_comp.jpg

Specifics; Meade 16 LX200 at f6.2 with Starizona reducer, Atik 460ex mono camera at -5C. Guided with Meade 107D 4 inch SCT and Qhy5L-II mono. Captured and stacked in Nebulosity, final in PS CS5, posted image about 46% full size to meet forum rules.

Clear skies,
Steve

Excellent Steve, and your composite comparison displays the contrast between the three clusters very well indeed. Nicely done and I appreciate you posting your results here.
Alan

Astro Sky 17.5 f/4.5 Dob || Apertura AD12 f/5 Dob || Zhumell Z10 f/4.9 Dob
ES AR127 f/6.5 & ED80 f/6 on Twilight-II || Apertura 6" f/5 Newtonian on Twilight-I
TV Ethos 100° 21mm, 13mm || ES 82° 24mm, 18mm || Vixen LVW 65° 22mm
Pentax XW 70° 10mm, 7mm, 5mm || barlows
DGM NPB Filter || Orion Ultra Block, O-III and Sky Glow Filters || Baader HaB Filter
Primary Field Atlases: Interstellarum and Uranometria All-Sky Edition
---------------------------------------------------------------------------
"Astronomers, we look into the past to see our future." (me)
"Seeing is in some respect an art, which must be learnt." (William Herschel)
"What we know is a drop, what we don't know is an ocean." (Sir Isaac Newton)
"The eternal silence of these infinite spaces frightens me...." (Blaise Pascal)
"No good deed goes unpunished." (various)
"I have become comfortably numb." (Roger Waters)
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Re: TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

#7

Post by John Baars »


In 2017 I was in Den Osse, a small village in the Netherlands. Bortle 4. For a city dweller rather dark. I had taken with me my Maksutov OMC140. I made a sketch of NGC6229. Now in 2022 I am back again on holiday and spotted NGC6229 again. It is a very nice and little globular cluster. When I am at home ( Bortle 8-9) no individual stars can be seen in the core. But here in Den Osse two or three can be glimpsed.The same goes for M13 and M92. Under darker skies more stars can be seen in the core. And even the "propellor" in M13.

For the sketch I used an exitpupil of 1 mm, so that is 140X in the OMC and 100X in the Vixen.
NGC6229 Final.jpg
Telescopes in frequency of use : * Vixen 102ED F/9, *SW Evostar 120ED F/7.5, *grabngo: SW 102 Mak F/13, *OMC140 Mak F/14.3, on Vixen GPDX.
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's: *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C8, * Meade 14 inch SCT on EQ8, *Lunt.
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Re: TSS Bi-Monthly DSO Challenge for July/August 2022 – a globular triple play x 2

#8

Post by kt4hx »


John Baars wrote: Tue Jul 26, 2022 7:13 am In 2017 I was in Den Osse, a small village in the Netherlands. Bortle 4. For a city dweller rather dark. I had taken with me my Maksutov OMC140. I made a sketch of NGC6229. Now in 2022 I am back again on holiday and spotted NGC6229 again. It is a very nice and little globular cluster. When I am at home ( Bortle 8-9) no individual stars can be seen in the core. But here in Den Osse two or three can be glimpsed.The same goes for M13 and M92. Under darker skies more stars can be seen in the core. And even the "propellor" in M13.

For the sketch I used an exitpupil of 1 mm, so that is 140X in the OMC and 100X in the Vixen.

NGC6229 Final.jpg

Excellent rendering of NGC 6229 and its field John, and thank you for your submission. Even though globular clusters hold up to brighter skies better than some other DSO types, they still reveal their best features in darker skies where we gain more contrast against the sky. I appreciate you presenting your sketching skills here, which highlights the level of detail one can achieve during the time required to sketch effectively versus a typical visual observation of less duration.
Alan

Astro Sky 17.5 f/4.5 Dob || Apertura AD12 f/5 Dob || Zhumell Z10 f/4.9 Dob
ES AR127 f/6.5 & ED80 f/6 on Twilight-II || Apertura 6" f/5 Newtonian on Twilight-I
TV Ethos 100° 21mm, 13mm || ES 82° 24mm, 18mm || Vixen LVW 65° 22mm
Pentax XW 70° 10mm, 7mm, 5mm || barlows
DGM NPB Filter || Orion Ultra Block, O-III and Sky Glow Filters || Baader HaB Filter
Primary Field Atlases: Interstellarum and Uranometria All-Sky Edition
---------------------------------------------------------------------------
"Astronomers, we look into the past to see our future." (me)
"Seeing is in some respect an art, which must be learnt." (William Herschel)
"What we know is a drop, what we don't know is an ocean." (Sir Isaac Newton)
"The eternal silence of these infinite spaces frightens me...." (Blaise Pascal)
"No good deed goes unpunished." (various)
"I have become comfortably numb." (Roger Waters)
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