TheSkySearchers

This month we will be following along (for the most part) the primary plane of our own galaxy, the Milky Way, sampling some of its riches. The northern summer and southern winter is rife with delightful nebulae of various types and myriad star clusters of both the open and globular variety. You will see we are heavily weighted into the objects of Charles Messier for this edition, as he has some of the finest in the skies within his short list. They make excellent visual and imaging objects and are frequently re-visited even by the most experienced members of our hobby simply because they are that good. So let’s get into this month’s selections for your viewing, sketching and/or imaging pleasure. I hope you like the journey whether you’re seeing these for the first time or the hundredth; they never get old.


Northern Celestial Hemisphere:

Messier 27 / NGC 6853 (Vulpecula, planetary nebula, mag=7.1, size=8.0’x5.7’, SBr=11.0):
This stunning planetary was discovered by Messier in 1764 and is the first planetary nebula discovered. It was independently discovered by Caroline Herschel in 1782 during only her second sweep as she was looking for comets.

Nicknamed the “Dumbbell Nebula” due to its bi-lobed interior structure, it is one of the premiere objects sought out during the northern summer nights. Bright and large (for a planetary) it is one of the first such objects (along with M57) viewed by beginners who are building their observing and/or imaging skills. With its higher surface brightness it is easy to pick up with all sizes of instruments, and clearly recognizable as a non-stellar object. With moderate aperture and scrutiny, it reveals its tell-tale dumbbell, or apple core or hourglass (whichever you prefer) interior structure. The planetary visually responds very well to a narrow-band nebula filter, as well as an O-III line filter. Its mag 13.5 central star may be glimpsed, plus there are several imposed foreground stars that may be picked up as well. This is truly an amazing object.

Messier 57 / NGC 6720 (Lyra, planetary nebula, mag=8.8, size=1.4’x1.0’, SBr=8.9):
The famous “Ring Nebula” is another northern summer staple for observers. Conveniently located nearly half way along a line from Beta Lyrae (Sheliak) to Gamma Lyrae (Sulafat), it is viewable by apertures small to large, though small scope will not reveal much detail. At a minimum it appears as a small ghostly orb, but with more aperture it turns into a smoke ring, with a strong annular structure and gauzy veil filling in its donut hole. With larger scopes, with a keen eye and steady seeing its mag 15.4 central star may be glimpsed and poses an excellent challenge.

Like most planetaries it responds well to both narrow-band nebula and O-III line filters. It was discovered by Messier on 31 January 1779 while looking for Bode’s Comet (the great comet of 1779). Sometimes we see references to discovery by Antoine Darquier in mid-February 1779, but his was an independent discovery and Messier deserves full credit. Regardless, give this perennial favorite a careful study and see just how much detail you can pull out. For those with larger aperture and darker skies, see if you can pick up the small barred spiral galaxy IC 1296 (mag=14.0, size=1.1'x0.9'; SBr=13.8) just 4’ northwest of M57. It presents an excellent challenge.

Messier 71 / NGC 6838 (Sagitta, globular cluster, mag=8.1, size=7.2’, class=11):
Sagitta the celestial arrow lies in a very rich Milky Way field between Vulpecula and Aquila. It is home to this very loosely structured globular cluster. Discovery credit for this object goes to Philippe de Chéseaux in the 1745-46 timeframe. Whether this is an unusually dense open cluster or a particularly loose globular cluster has been the subject of speculation. Initially classified as the former, a study in the 1970s determined it was actually more akin to the later type of object.

Regardless of all the confusion surrounding its true physical nature, it is indeed a curious object worthy of our attention. This beautiful cluster appears as a hazy concentration within a rich Milky Way field using smaller apertures. But as one increases aperture and magnification, it resolves nicely into a concentrated scatter of stars, well detached from the field and overlaying a hazy backdrop of deeper members. While it is not the rival of some of the more majestic globulars well known to observers and imagers, it is still an entrancing object that should be studied more closely, and I encourage you to do so.


Southern Celestial Hemisphere:

Messier 8 / NGC 6533 (Sagittarius, bright nebula, mag=5.8, size=90.0’x40.0’):
The infamous “Lagoon Nebula” is a thing of beauty and many parts. The designation of NGC 6533 is the whole complex which was first noted by Giovanni Battista Hodierna sometime before 1654. The whole of M8 is comprised of NGC 6523 (northwestern brightest section), NGC 6526 (southeastern dimmer portion) and NGC 6530 (open cluster in the eastern portion). There are also some dark nebulae present that give it an uneven texture. Additionally there are two smaller portions of nebulosity that may or may not be part of the greater complex. IC 1271 is a small bit of nebulosity illuminated by the mag 6.9 star HD 165052 east of the cluster NGC 6530. Another is IC 4678, which is a small halo of nebulosity less than a degree northeast of the center of M8. These last two sections are not typically considered when one things of the larger nebular complex however.

But any way you slice it, M8 is an outstanding visual and imaging treat. Bright and showy at any aperture level, it responds very well to a narrow-band nebula filter, which boosts its contrast significantly. Using an O-III filter is also rewarding. While it dims some of the fainter outer portions, it enhances the darker central regions nicely. If one has both, it is always an interesting comparison to apply each and compare the changes in the view. Even if you’ve seen this object numerous times, it will never disappoint. If you observe from a darker region you are in for a fine display through the eyepiece, and be sure to look for it with the naked eye.

Messier 20 / NGC 6514 (Sagittarius, bright nebula, mag=6.3, size=29.0’x27.0’):
This object is quite unique, as its nickname of “Trifid Nebula” would seem to imply. Noticeably smaller than Messier 8 and a bit dimmer, it still is a beautiful nebula complex, consisting of emission, reflection and dark elements. Discovered by Messier in 1764, he noticed the central star cluster (known to us as OCL-23). William Herschel is the one who noticed “three nebulae” while his son John was the first to utilize the name “Trifid” to describe the nebula. Less than 1.5° NNW of M8, it is easily seen in small apertures within the same field of view. If you have a narrow-band nebula filter in your kit, give it a try to bring out some more contrast.

From darker locations it shows up wonderfully through the eyepiece and is visible with the naked eye just above M8. Also from darker locations, see if you can spot its dimmer reflection portions, predominantly in the northern section of the complex. While it is not quite the showpiece that M8 is visually, M20 is no slouch and presents an interesting visual and imaging target.

NGC 6188 (Ara, bright nebula, mag=unk, size=20.0’x12.0’):
NGC 6193 (Ara, open cluster, mag=5.2, size=15.0’, class= II3p):
This nice complex is sometimes called the Firebird Nebula and Cluster. Located in northwestern Ara near its border with Norma, the discovery of this field is split between James Dunlop and John Herschel. Dunlop discovered the cluster, later designated as NGC 6193, in 1826 but did not mention any nebulosity in his notations. Herschel formally discovered the nebula in 1836 and also observed the cluster, mentioning both in his discovery notes.

Though the cluster is swaddled in nebulosity, the brightest portions of the nebula lie immediately west of the bright young cluster, which is an OB1 association. Like many such nebular complexes, it consists of both emission and reflective elements, and images also reveal strands of dark obscuring matter traversing the field. This field is a beautiful combination of young hot stars still wrapped in their womb of nebulosity, and one that I’ve had the pleasure of observing a couple of times. I hope you enjoy it as well.


Rest assured the above objects are but a minuscule sampling of the treats available to us during the month of July. The main take away here is to get out there whenever time and weather permit. So let's all get out there and turn our scopes and attention skyward to enjoy the wealth of sights the universe has spread out before us. It is indeed an unlimited buffet for the eyes and the mind.

Thanks for this month's targets, Alan.

Hopefully I can get out at some point this month....whew. Rain and clouds!

KingNothing13 wrote: ↑Thu Jul 01, 2021 5:20 pm Thanks for this month's targets, Alan.

Hopefully I can get out at some point this month....whew. Rain and clouds!

Thanks Brett. We have been having clear skies mostly but its been very hot and humid, so not particularly conducive for getting out either. All that humidity makes the sky glow at home more pronounced. Hope to get over to the dark site this coming weekend. Good luck and look forward to your observations.

Thanks for that Alan.

I've not seen any of these since my DSLR days! Hopefully the builders will be done in time to get the telescope out of storage to have another go at them with the ZWO. Otherwise it will be a PI reprocess submission from me!

Regards

Graeme

Graeme1858 wrote: ↑Thu Jul 01, 2021 9:05 pm Thanks for that Alan.

I've not seen any of these since my DSLR days! Hopefully the builders will be done in time to get the telescope out of storage to have another go at them with the ZWO. Otherwise it will be a PI reprocess submission from me!

Regards

Graeme

Thank you Graeme. I hope things work out so you can get the kit back out under the sky. While reprocessing is possible, I should think you are getting the itch to pull down some new photons!

kt4hx wrote: ↑Thu Jul 01, 2021 9:58 pm I should think you are getting the itch to pull down some new photons!

Definitely!

Well, I posted a version of this shot in the astrophotography section a couple days back, so the details on exposures etc. are there, basically 20 min OSC, 30 min Ha, thru Rokinon 135mm and AS1600MC-cool. Just re-did the Ha color overlay for this version, I like it a bit better, but maybe overcooked for some.

What is cool, with this moderate angle lens, is the number of cataloged DSOs in just one shot. M8 and M20, the biggies, but M21, the OC to the north of M20, and NGC6544, a small glob south of M8. Also, the obvious extensions to M8 off to the east have NGC and IC designations for all the lumps too. ICs 1271,1275,4678,4684, NGCs 6546,6559, and some dark nebulae that I didn't chase down. Some of these are nebulae others OCs, but I find the sparse OCs hard to differentiate from the overall milky way background.
Clear skies,
Steve

sdbodin wrote: ↑Sat Jul 10, 2021 1:47 am Well, I posted a version of this shot in the astrophotography section a couple days back, so the details on exposures etc. are there, basically 20 min OSC, 30 min Ha, thru Rokinon 135mm and AS1600MC-cool. Just re-did the Ha color overlay for this version, I like it a bit better, but maybe overcooked for some.

What is cool, with this moderate angle lens, is the number of cataloged DSOs in just one shot. M8 and M20, the biggies, but M21, the OC to the north of M20, and NGC6544, a small glob south of M8. Also, the obvious extensions to M8 off to the east have NGC and IC designations for all the lumps too. ICs 1271,1275,4678,4684, NGCs 6546,6559, and some dark nebulae that I didn't chase down. Some of these are nebulae others OCs, but I find the sparse OCs hard to differentiate from the overall milky way background.



Clear skies,
Steve

Excellent Steve and thank you for posting your image here as well. In your wide field there is a lot going on as you indicated. Agree, it can sometimes be challenging to identify some of the clusters from the very rich general field in this part of the sky.

I took a quick look at the Ring and Dumbbell last night with the OIII Filter.

The Ring and Dumbell were stunning with the OIII filter - The Ring was a bright blue, the hole was evident with averted vision. The Dumbell was bigger with the OIII than I remember it being without (I did not check it without). Very nice, large puff ball.

Thanks Alan!

KingNothing13 wrote: ↑Sun Jul 11, 2021 1:30 pm I took a quick look at the Ring and Dumbbell last night with the OIII Filter.

The Ring and Dumbell were stunning with the OIII filter - The Ring was a bright blue, the hole was evident with averted vision. The Dumbell was bigger with the OIII than I remember it being without (I did not check it without). Very nice, large puff ball.

Thanks Alan!

Thank you Brett for posting your quick looks here. Both objects are beautiful indeed, but in their own unique way. I envy those that see color in M57, as I never have.

kt4hx wrote: ↑Sun Jul 11, 2021 4:56 pm

KingNothing13 wrote: ↑Sun Jul 11, 2021 1:30 pm I took a quick look at the Ring and Dumbbell last night with the OIII Filter.

The Ring and Dumbell were stunning with the OIII filter - The Ring was a bright blue, the hole was evident with averted vision. The Dumbell was bigger with the OIII than I remember it being without (I did not check it without). Very nice, large puff ball.

Thanks Alan!

Thank you Brett for posting your quick looks here. Both objects are beautiful indeed, but in their own unique way. I envy those that see color in M57, as I never have.

I only saw color because of the OIII filter. It turned some bright white stars a beautiful blue color

KingNothing13 wrote: ↑Sun Jul 11, 2021 5:31 pm

kt4hx wrote: ↑Sun Jul 11, 2021 4:56 pm

KingNothing13 wrote: ↑Sun Jul 11, 2021 1:30 pm I took a quick look at the Ring and Dumbbell last night with the OIII Filter.

The Ring and Dumbell were stunning with the OIII filter - The Ring was a bright blue, the hole was evident with averted vision. The Dumbell was bigger with the OIII than I remember it being without (I did not check it without). Very nice, large puff ball.

Thanks Alan!

Thank you Brett for posting your quick looks here. Both objects are beautiful indeed, but in their own unique way. I envy those that see color in M57, as I never have.

I only saw color because of the OIII filter. It turned some bright white stars a beautiful blue color

I sort of wondered about that, but was giving you the benefit of the doubt. That said, I have read of some folks that see color in M57 (without a filter), which I do indeed envy.

I observed them two evenings on a row. The first time with my 120mm Evostar, the second evening with my 150mm Startravel. Thanks to the grey Summer night, bit milky skies too and the Moon looking over my right shoulder, they weren't all that impressive as I am used to. The smoky Ring as well as the Dumbbell were quite obvious though.
M71 is another story. I observed this globular in both telescopes, it is obvious that atmospheric conditions and a one day older Moon had their impact, even though I had a bigger telescope the second time. The first night I saw some individual stars in it and some grey granulation of other stars. Second night ( with the somewhat bigger scope ) that had all disappeared and just a difficult to spot blur appeared. I found it a bit disappointing even, but once again learned from it that the skies often are a more decisive factor than your aperture.
To my surprise the 6 inch refractor took more than one hour to cool down to equilibrium, a record, where it normally does the trick in less.

John Baars wrote: ↑Mon Jul 19, 2021 3:57 pm I observed them two evenings on a row. The first time with my 120mm Evostar, the second evening with my 150mm Startravel. Thanks to the grey Summer night, bit milky skies too and the Moon looking over my right shoulder, they weren't all that impressive as I am used to. The smoky Ring as well as the Dumbbell were quite obvious though.
M71 is another story. I observed this globular in both telescopes, it is obvious that atmospheric conditions and a one day older Moon had their impact, even though I had a bigger telescope the second time. The first night I saw some individual stars in it and some grey granulation of other stars. Second night ( with the somewhat bigger scope ) that had all disappeared and just a difficult to spot blur appeared. I found it a bit disappointing even, but once again learned from it that the skies often are a more decisive factor than your aperture.
To my surprise the 6 inch refractor took more than one hour to cool down to equilibrium, a record, where it normally does the trick in less.

Thank you for posting of your recent challenge activity John. Unfortunately for many, the richness of the summer sky is subject to summer weather conditions. In particular the higher humidity, which amplifies the impact of our sky glow.

M71 is a tricky beast to be sure. I have observed it with apertures ranging from 10x50 binoculars to the 17.5 inch and under skies ranging from Bortle 6 to Bortle 2. Because of its loose structure and its position in such a rich stellar field, it is impacted more by variable sky conditions than more condensed globulars of similar brightness.

Hi all I have already posted in the Deepsky objects and Graeme contacted me to put on the monthly challenge,so here are M27 and M57. Thanks

andrewsscope wrote: ↑Wed Jul 21, 2021 9:10 pm Hi all I have already posted in the Deepsky objects and Graeme contacted me to put on the monthly challenge,so here are M27 and M57.

Thanks

Thank you Andrew (and thanks to Graeme). Your images are wonderfully detailed. I see you also captured the galaxy IC 1296 northwest of M57. This is a challenging visual target which I have seen at our dark site with the 17.5 inch.

Please be sure to check here each month and if you do image any of our challenge objects I encourage you to post them here, even if you have posted in the AP area. In this case, duplication is a good thing!

Here's my PI reprocess of M27 captured on my 600D 22/08/19. It's much better than my previous processing attempt!

Graeme1858 wrote: ↑Sat Jul 31, 2021 8:08 am Here's my PI reprocess of M27 captured on my 600D 22/08/19. It's much better than my previous processing attempt!

Now that is a beautiful image Graeme - well done!

A day late but Aug 1 was the first clear moonless night in a few weeks with an opportunity to try this.

Instrument: 18" f5.5 Dobsonian
Eyepieces used: Seeing: 2/5 improving through the evening
Transparency: 8/10
Bortle Rating: Not allowed to mention my dark sky rating (Andrey doesn't like it)

Bigzmey wrote: ↑Sat Jul 24, 2021 4:31 am If you can see something like that on regular basis, count your blessings. It's like saying why can't you guys get Bortle 1 sky, it is so easy for me.

The ECMWF weather modelling indicated totally clear skies for days beforehand. I had an appointment in Canberra the next afternoon and was going to drive down Sunday. In view of the forecast, I decided to stay the night and drive down the next morning. The weather didn't disappoint and heavy cloud broke up during the afternoon as predicted, completely clearing about an hour after twilight.

This month, both north and south hemisphere objects were available at my latitude so I decided to try the lot. I also decided to try my hand at some sketching for the first time in many years. Please don't laugh!

I set up the 18". It was stored in the shed and I'd left the doors open from late afternoon so it didn't need much cool down time. I started the evening with a quick look at Jupiter and Saturn. With the Pentax XW10 (250x) the image was just a blur seeing was poor early on. When my eyes were dark adapted, I began the hunt.

M57 Ring Nebula
With Lyra sinking into the trees to the north & northwest, I didn't waste any time in viewing the Ring Nebula. The donut is very bright but I could not clearly see the central white dwarf(Mv 15.8) with the 31mm. I thought I detected the occasional flicker coming from a star in the centre but not certain with the 17mm.

M27 Dumbbell Nebula
17mm. The Dumbbell is so-called because of the two bright lobes. In the 18", the full sphere of nebulosity is easily visible. Both lobes and the connecting fainter nebulosity.

M71 Globular in Sagitta
17mm. As in Alan's notes, my first impression of this has always been, "Really, a globular?" It is an interesting object in as much as it looks very open for a globular cluster. The 18" with it's 2500mm focal length and resolution really opens up even very condensed globular clusters so this one looks very open.

NGC6188/NGC6193
31mm. Though I have seen many narrowband images of the "Fighting Dragons of Ara" over the years, I had never observed it visually. It is an expansive object but even with my 18" in a dark sky, the nebulosity, though extensive is faint and nuanced. The reflection nebulae around some of the illuminating stars and the brighter linear nebulosity, the dragons heads, are the most visible features. Faint nebulosity is visible through the entire region.
M8 Lagoon Nebula
31mm. I have observed this large bright expansive nebula on many occasions through a variety of instruments. The centre of the lagoon, prominent in many photographs was barely visible. Nonetheless


M20 Triffid Nebula
31mm/17mm. Excellent contrast between the dark lanes and nebulosity. The "Triffid" morphology of this nebula is better represented in a smaller instrument. Larger instruments pick up a greater extent of nebulosity which, while interesting is a little less "triffidesque " to my eye.
It was approaching 11pm. With a 2hr drive and a medical appointment in Canberra the next afternoon and dinner with friends last night, I didn't want to make an all nighter of it. With good transparency, I devoted another hour to a quick scan of some favourite objects. NGC4945 is a large edge on spiral in Centaurus, more or less due north of Crux. At mag 9.3 its surface brightness is quite faint due to it's large extent, 20 mins long though only 4 mins high. While in the neighbourhood, I jumped over to NGC5128, the galaxy associated with the Centaurus A radio source. Grus was by now high in the sky and so I checked out the quartet of galaxies NGC7552, 7582, 7590, 7599. These 4 moderately bright galaxies fit nicely within the 1 degree diameter field of my 31mm Nagler as shown in the illustration taken from Starry Night Pro.
Finally I went over to Jupiter and Saturn. The seeing had improved very slightly. At 250X with the XW10, Saturn, at a nosebleed inducing altitude of 73 degrees was more stable than Jupiter at 59 degrees. I had brief instances of a few seconds of stability on Jupiter and a few more seconds on Saturn. I thought I glimpsed a hint of the elusive Encke division but I could not be certain. On other occasions, with perceived better conditions, I have not seen it. Jupiter was much less rewarding. It was after midnight and I wanted to pack the scope away so I could sleep in and make a quicker departure for Canberra in the morning.

Joe

Excellent, excellent report Joe! Nothing wrong with your sketches in the least. Since I do not sketch at all, I find them very nice.

Glad you were able to observe all the objects, and never worry about being a day or a month late. As long as the objects are in the sky, they are fair game. I only wish I could see NGC 6188 and 6193 with my 17.5", as my humble efforts with the 80mm a few years back pale in comparison. I often found myself wishing I had more aperture during those trips!

And thank you for highlighting the Grus quartet. While I have seen it with smaller aperture, I need to try and scrape it from just above my horizon at the dark site!