Butch’s time with the CfA2 Great Wall of Galaxies observed
Guest post from Butch: Perhaps appropriately, this report is quite lengthy, as is the Great Wall itself.
Some of you know this story already, but for those who don’t… I’m rather new to deep sky observing, starting in the summer of 2021. Astronomy, particularly manned space travel, has been an avid interest of mine since my childhood in central Florida, when Mercury, Gemini and Apollo captivated us all, watching launches at the Cape from my front door and following all the TV coverage. But a seminal moment for me was reached in the mid-90s when I read Voyage to the Great Attractor. It was my introduction to the idea of a universe composed of massive structures. Not just galaxies but hundreds to thousands bound in superclusters, filaments and walls. The scale was breathtaking. A short time later, a friend bought a used 8” Cassegrain and we looked at M31. I was overwhelmed and then hooked. I subscribed to S&T and read everything astronomy related that I could get my hands on. I didn’t always understand what I read, but I kept at it. Without the funds for a telescope, my wife gifted me a pair of Orion Little Giant II binoculars (20x70) and I began looking, but not very systematically. I’d also run astronomy clubs for 2 high schools for a total of 15 years. Over 20 years after reading Voyage I was asked to teach the honors astronomy class at my high school on the recommendation of the outgoing science teacher who had set up the course. I was teaching social studies across the hall, and we got into many technical conversations and drove together to see the total eclipse as it passed through Newberry South Carolina in 2017. None of the science teachers had room in their schedules, nor the inclination to teach the course, so for the next five years I was an adjunct member of the science department. Upon retiring in 2021, I gifted myself a 10” Sky Watcher Dob, joined the Charlotte Amateur Astronomer’s Club, and my observing journey began.
Back in 2002, I had visited CAAC’s observatory with my previous school’s astronomy club. It was then that I was first acquainted with the 24” f/5 built by club member Gayle H. Rigsbee, for whom the observatory is named. The views Gayle showed us of Saturn and particularly M42 blew me away, and I longed for an instrument like that, still drawn to very distant objects and structures. When I joined the club nearly 2 decades later, 10” Dob in hand, I learned to my amazement that the 24” was free for trained members to use! Why didn’t I join sooner? Now I had the right instrument to go very deep. My first view of a galaxy cluster associated with the CfA2 Great Wall was Abell 1367, the Leo Cluster, in April of 2022. Abells 2197 and 2199 followed in August of the same year. The Coma Cluster, Abell 1656, was next in April of 2023. Doing a little research, I learned that those four clusters were part of the Great Wall, and the idea of an observing project began shortly after, to observe and draw the associated Abell Clusters. The vast spaces between them are thinly populated for the most part and by comparison. The following year (2024) I was finally able to see galaxies in Abell 2151 and thought my observation of the Great Wall was complete. No. Abells 2147 and 2152 had been found to be in that structure and perhaps others in the Hercules Supercluster. I also realized after viewing 2151 that the previous observations would need to be revisited and revised. This past summer I was able to observe Abell 2152 and a portion of 2147 as well as revisit portions of 2199, 2197 and a bit of western 2151. Alas the journey is not yet complete, and Hercules is getting into the light dome of Lancaster, SC on the western horizon. But I’ve observed most of each of the clusters in that vast structure and am fairly confident that I’ll be able to fill in what remains within reasonable expectation next spring and summer. I’ve been itching to share this project with like-minded friends. Here let me apologize to Keith Rivich – this is why I’ve not pursued your excellent monthly challenge lists since late spring!
The CfA2 wall was named after China’s Great Wall by Margaret Geller and John Huchra who co-discovered it in 1989 while analyzing data from the second Red Shift Survey conducted by the Center for Astrophysics | Harvard and Smithsonian. It still remains one of the largest known associations in the universe, winding from well to the west of Leo to the Hercules Supercluster in a broad, serpentine fashion, snaking its way for half a billion light years, with a width of 300 MLY and a thickness of 15 MLY, kind of like a great, cosmic lasagna noodle. At its center, the Great Wall is at an average distance of 310-330 MLY, and much further away at its eastern end, at an average of 500 to 600 MLY. Some individual members of Abell 2152 are in the neighborhood of 680 MLY distant. From west to east, the associated Abell groups are 1367, the Leo Cluster, 1656 the Coma Cluster, and the 5 clusters in Hercules – 2197, 2199, 2151 the Hercules Cluster, 2147 and 2152. Those 5 latter clusters together compose the Hercules Supercluster. On the sky The Great Wall of Galaxies is vast, covering around 25% of the nighttime dome from late spring to late summer.
What follows is a compilation of the observing reports and sketches of the fields of view that were produced at the time of viewing. The earliest one - Abell 1367 – needs a revisit and complete revision. You’ll also note that the reports themselves get more detailed, the more current they are. (I really was in over my head at first.) The others need some additional fields to capture either the complete cluster and/or significant sub-groupings of galaxies just outside the official borders found in charts. Recently noting that my go-to resource – Pretty Deep Maps – does have some issues with identification (it’s still a great tool), I’ve gone through the reports and drawing labels, cross-checking with Aladin Lite, CzSky (Thanks Brent!), WikiSky and other resources and making needed corrections. I’ve found some labelling errors and corrected them, but there may be others I’ve missed. As you know, for some galaxies there is disagreement and/or confusion between catalogues as to the correct identification., Abell 2151 likely the worst of them. To be honest, this has been the most tedious and frustrating aspect of the project. If you know of corrections that are needed, a PM would be appreciated. The numbers following the slash after galaxy designations are the galaxy magnitudes listed in Pretty Deep Maps and/or Aladin Lite.
Given the forum’s file size limitations, I’ve hyperlinked the sketch image files in the following reports, and I recommend opening two windows alongside one another – one for the report(s) and another for the images. In order to best see the galaxies in the drawings I also recommend using a monitor rather than a phone, darkening the room and enlarging the images. That will involve going back and forth a bit, but I don’t know how else to do it. You may also want to brighten your monitor screen setting. Each field will have both an unlabeled and labeled version. Also note that all sketches were created in the Mellish technique of applying white pastel powder to black multimedia paper by brush and white pastel pencils or white gel pen for stars. Given the small apparent sizes of these galaxies, a 12/0 mini angular brush was used for most of them as well as the cores and/or any other details.
I’ll start in the west.
Abell 1367, the Leo Cluster:
Field = 21’
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This was my first Abell group observation and less than a year into observing. I was still working on averted vision, and didnt begin writing detailed observation reports until maybe a year later. Nor did I know how to approach a galaxy cluster of this size then. I had found the grouping in the Night Sky Observer’s Guide and had no idea that Abell groups existed. Focused on just that sub-grouping, I stayed with medium power and FOV – a 13mm TV Ethos @ 235x, unknowingly missing many members of the cluster. Truth be told I doubt I would have seen many of them at all.
Abell 1367 is approximately 330-370 MLY distant and is situated near the middle of CfA2. About 70 major galaxies make up the principal members, of which NGC 3842 is dominant. Along with Abell 1656, the Coma Cluster, the Leo Cluster is a component of the Coma Supercluster of galaxies. This cluster needs to be revisited next spring.
This observation report will be brief and is based on my eyepiece notes next to the eyepiece sketch made 3 years ago.
Observing: 4/19/2022 Conditions were clear and chilly, with transparency better than average and seeing about average. (I was not using a sky meter to measure darkness, so used the Bortle 4.5 rating that the club uses for GHRO.)
A moderately bright star occupied the center of the field of view, and the large fuzzy halo of NGC 3842 was just to the south of it. The core was clearly brighter than the round halo. Averted vision extended the halo and rendered the core and nucleus nearly star-like.
Averted vision showed a handful of other fuzzies surrounding NGC **38**42 and extending to the edges of the field of view. In my notes I wasn’t sure that I got all of them into the sketch, and described them as very, very faint. NGCs 3842, 3837, 3861 showed cores and 4 were noted being mistaken for stars at first. Those were not identified and may or may not overlap with the 3 just mentioned.
I do remember being thrilled at seeing “so many” galaxies in one field, and this observation was certainly a step along the path to seeing fainter and more distant targets. I did not realize at the time that I was looking at part of the Great Wall. Next visit I will be more prepared and hopefully more successful.
Abell 1656/The Coma Cluster in Coma Berenices
Field = 30’
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This grouping has a mean distance of 321 MLY, and along with Abell 1367/The Leo Cluster combines to make up the Coma Supercluster. Abell 1367 was observed almost exactly a year before, and this observation confirmed the need to go back to see more of its members. AOC 1656 is a giant with over 1000 members, dominated by NGC 4874 and NGC 4889.
Observing: 4/17/2023 Not quite so cold this night, and the breeze had calmed. Transparency 4-5/5 but poor seeing of around 2/5. Used the 21mm at 145x to gather in as much of the group as I could. Some members were left out of the FOV, including a nice interacting pair to the north – NGC 4841 A/B. The star field was relatively sparse, save for bright HD 112887 (mag. 7.2) shining a little to the NW of the center of view.
NGC 4874 and NGC 4889 were the first seen, and easily the largest and brightest. Both are giant ellipticals. (4889 is perhaps the largest within 100 Mpc of us) The other members seen were all quite small. No surprise at those distances. Frankly at first it was just bewildering as small AV smudges seemed to be popping out all over. It took about an hour of looking to make sure of each one and its placement. I really didn’t want to put down two where I only really saw one.
NGC 4874 and NGC 4889 were not only the largest and brightest, but also the only two to be seen directly with any consistency and to show any detail in a brightening toward their centers. 4874 was rounder than 4889 which was elongated east to west.
Rather than describe each separate galaxy let me just say they were all pretty much AV objects that showed little if any detail. Of those, NGCs **4906, 4864, 4896, 4908 and 4898** showed stellar nuclei.
The close visual companions of 4889 deserve a mention. I couldn’t find out if they’re interacting with the nearby monster, however. 4886 was tiny and very hard to pick out as it got lost in the glow or halo of 4889. 4898 and 4894 almost overlap and appeared just to the south of 4889 mostly as two close stellar nuclei. Their tiny halos were also tough to separate not only from 4889 but from each other. Also, 4898 is a double with PGC **3098454**. I’m not sure if I split the cores or not as it got very tight in there.
Had to take a mental break after this one. But I was really stoked to look at the field sketch and count 21 galaxies – far and away the most I’ve ever seen at once (as of that date). I know there are many more that I didn’t see but was pretty happy with this haul.
The identification process took some time. That was accomplished using photos, Pretty Deep Maps and The Webb Society Deep Sky Observer’s Handbook, vol. 5 Clusters of Galaxies. I won’t say I’m 100% certain of all of them, but I think the cross-checking helped narrow things down pretty well. (I recently went back and checked the labels against Aladin Lite and CzSky, making a few corrections.)
Abell 2197 in Hercules
Field = 30’
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Unexpected clear skies with very good transparency and seeing enabled me to finally re-observe Abell 2197 after 3 years and, as expected, many more members were seen this time around. It was a last-minute decision to go and glad I did. I usually get that wrong. Not this time. A more complete drawing and report were the result, as I didn’t really have much in the way of notes the first time.
AOC 2197 has a mean distance of 420 MLY and has at least 70 major members of which NGCs 6160 and 6173 are dominant ellipticals. The distance to those are 467 MLY and 460 MLY, respectively.
Observing: Conditions on August 14, 2025 were unexpectedly clear but muggy. However, the forecast for poor transparency was way off. 9,800-10,00 ADU was one of the better nights in months, and seeing was very good to excellent at <1.5 a/sec. At 21.2 the SQM reading was a bit brighter than the usual 21.4 of the last months. I’m going to blame the Charlotte, NC light dome for at least some of that, along with clouds low on the horizon in that direction (NW) and to the south that were reflecting light from Lancaster, SC to the west and the 24/7 goldmine to the southwest. The forecast tools looked doubtful but GOES satellite imagery convinced me to go. Good thing!
30 minutes before astronomical dusk at 9:44PM, the starfield was recognized and both NGC 6173 and 6160 were easily seen at 145x. The 21mm Ethos was able to include nearly all of the cluster, leaving just a handful of members that could possibly be detected out of the field of view. The 21mm was used for the large field of view and re-orientation after a deep dive for specific members. Most observations were made with the 8mm Ethos @ 381x, with occasional use of the 2x PowerMate for 762x since the good seeing allowed it. (I’ve found that although the Orion 40mm takes in a larger field it’s just not as sharp as the 21mm Ethos, which has better light transmission and is sharp to the edge.)
I decided to begin with the chain of galaxies between NGC 6173 and NGC 6160, starting with 6173 and the galaxies surrounding it.
NGC 6173/12.1, a LINER and giant elliptical galaxy, was a 2:1 oval with a PA of 320° and halo dimensions of 2.4’ x 1.2’. Easily held in direct vision mostly due to its brighter core, the full extent of the halo was best seen with averted vision. The core was clear and bright but not stellar. It also helped to get HD 149025 blazing at mag. 7.8 out of the field for the best view of 6173 and other galaxies close by.
An arc of four optical mag 15+ companions partially surrounded 6173 from east-northeast, curving north, then southwards and further west to west-northwest. All were also much smaller than 6173.
The easternmost of those, about 2’ east-northeast of 6173, was PGC **58358**/15.9 showing only as a round, even smudge of maybe 0.5’. It was an averted vision object 50% of the time. (A couple sources identified this galaxy as NGC 6714.)
Next in the arc to the west was the overlapping pair of NGC 6714/15.7** and a galaxy whose identity seems to be in some disagreement, but more often than not, **PGC **58350**/16.8. The two showed as one slightly elongated smudge of 1.0’ x 0.8’ oriented 315°, but I could not make out two cores. The smudge with brightened center, certainly NGC 6714, was visible directly at times but was consistent in averted vision.
PGC 58334/15.3 was the most visible of this little group and popped in direct vision regularly. It sat about 10’ west of 6714, at the intersection of a line due west from NGC 6174, and another following the long axis of 6173. A perfect round smudge of 0.9’, it displayed a clear bright core.
5’ to the west-southwest the AV smudge of PGC 58321/15.5 persisted with a suggestion of a brightening in the middle of a 2:1 halo of 1.0’ x 0.5’; PA 290°.
Another 5’ west is a pair of stars that were bright at 381x and mark the approximate midpoint of the galaxy chain on its way to NGC 6160. Just beyond that marker, and closer to the southern star was the faint circle of PGC **58298**/15.7. Primarily an averted vision object of perhaps 0.7’, it persisted as a smudge just to the right of the marker star and slightly above it (northwest).
Another 15’-20’ west-northwest was a very dim line of four galaxies running roughly perpendicular to the direction of the chain, almost like an advanced defensive line for 6160. From north to south, these were PGCs 2173685/15.9, 2173123/16.5, 87321/16.0 and 3388198/15.6. Only PDM identified the fourth galaxy. All four were tiny round smudges of 0.5’-0.3’ best seen in averted vision, although the brighter two (one and four, north to south) were held direct around 50% of the time and showed brightening towards the middle.
PGC 214500/15.8 was just 2’ to the west of NGC 6160 and barely made out, being detected only in averted vision a handful of times as a faint dot with no detail. I hesitate to post a dimension, but maybe 0.3’?
About 5’ due south of NGC 6160 was PGC** 214502**/16.1. In appearance and brightness it was a twin of PGC 214500.
Finally came to NGC 6160/13.2 which had been visible in the 8mm since the row of 4 to the east. It was bright and always visible in direct vision (something of a relief at the time), although the full 1.5:1 halo of 2.2’ x 1.5’ was seen in averted vision. AV also helped to confirm a PA of 75°. The core was distinct and round, and much brighter than the rest of the galaxy. A handful of times I thought a stellar nucleus winked out. Although listed as a magnitude fainter than NGC 6173 it appeared brighter to me than its giant elliptical companion.
Went back east to the NGC 6173 neighborhood to pick up galaxies to the northeast and southeast to southwest of the co-dominant elliptical. To the northeast were two galaxies that formed a shallow trapezoid with two bright stars that form a line from just east of 6173 and extending to the northeast. The galaxies parallel that line, forming a shorter one to the west and centered on the two stars. PGC 58377/15.6 and PGC** **3388174/15.8 were both averted vision objects that showed no detail. Both were round in appearance even though 3388174 shows as a thin slash in photos. It was tiny at only 0.2’. PGC 58377 was slightly larger at 0.5’. I didn’t spend too much time on them as there were other fish to catch elsewhere in the FOV.
South of HD 149025 was a group of 12 or so small galaxies, including a Vorontsov-Velyaminov pair of somewhat larger and overlapping galaxies, but I was only able to see 3 of them, including the overlapping pair. Due south of HD 149025 was PGC 58378/15.4, a round AV smudge of 0.8’. The larger pair of galaxies – NGC **6**175/14.8 and UGC 10422/15.0 make up** VV 1816** and were held in direct vision on and off for at least half the time but persisted in averted vision. The largest galaxies in the field after 6173 and 6160, the combined halo measured 2.0’ x 1.5’ with a PA of 265°. The two cores could not be split, and the halos could not be distinguished from each other. These two galaxies are just outside the recognized group boundary.
A rough grouping of at least 2 dozen galaxies runs from this area as far west as 6160 and roughly parallel to the chain described earlier. I was able to see four of them but think I could have pulled in more if I’d had more time. The first of these was PGC 2169974/15.9 which was the point of a scalene triangle formed with NGCs 6173 and 6175. Seen in averted vision only, it showed as a circular and even brightness smudge of 0.3’. I may have seen a stellar nucleus wink into view 2-3 times. PGC 169660/15.8 was next, perhaps 10’ to the southwest. Also a circular AV smudge of 0.3’, this one showed no stellar nucleus. Just south of the center of the FOV was a bright right triangle of stars, the westernmost of which marked tiny PGC **2169956/16.5 maybe 3’ to its southeast. Another 4’ southwest was **PGC 3388197/15.7. Both of these galaxies were circular averted vision objects of 0.3’, visible perhaps 30% of the time.
Observing the next subgroup began with reorienting by going back to bright NGC 6160. To the north-northwest of 6160 is an isosceles triangle of 3 bright stars pointing roughly north. A fairly bright outlier galaxy was due east of the center of the triangle. That was PGC 3388179/15.3. The 50% direct vision galaxy showed a somewhat brighter middle in a 2:1 halo that measured 0.8’ x 0.4’ with a PA of 290°.
Further to the east-northeast was a significant and tight subgroup of galaxies that were a bit tough to pin down despite magnitudes in the 15s. They were arranged in a half-circle of 5 galaxies open to the southwest and one overlapped group of 4 galaxies – VV 1813 – positioned about 5’ due north of the half-circle of 5.
Starting with the southernmost galaxy of the group of 5, PGC58266/15.4 presented a round halo of around 0.6’ with a clearly brighter middle. That description works for the other galaxies as well, with slight variations in sizes – the middle two being slightly smaller. 2’ north-northeast was PGC 58268/15.3, with PGC 58264/15.7 back to north-northwest and the pair of PGC 58249/15.3 and PGC 58248/15.1 due west of that. The grouping fit nicely in the field of view of the 8mm. Surprised this group was not included in the Arp or Hickson catalogues.
5’ north of the half-circle of 5 sat VV **1813** that in photographs is a glorious trainwreck of interaction. Visually, however, it was a bit disappointing. I was unable to split the halos and didn’t expect to as closely as the galaxies overlap. But I was hoping to pick out the separate cores. It wasn’t to be, as the group was one 0.6’ smudge with a brighter central area. The group is dominated by UGC 10407/14.6 and also includes the PGCs 3440721/16.4, 4530639/16.5 and 4543025/16.5.
More hurried than I would have liked, I still consider this one a successful observation for purposes of the CfA2 project, including a fair representation of Abell 2197’s galaxies even if some were left out that might have been seen with more time spent hunting them down and lingering enough for the dim glows to show themselves. It was also satisfying in that not too many members lie outside the group boundaries as is the case with some of the other Abell groups.
Addendum from 8/29/2025
An unexpected clear night with Hercules still near zenith, so the Charlotte and Lancaster light domes weren’t a factor until later. The 38% illuminated moon didn’t set until 11:04PM, but it was behind the trees a half hour before that, and it made a surprising difference. I was able to go back to pick up a couple galaxies I felt I should have seen and get better confirmation on a few others. Here are the additional observations:
UGC 10407 showed a stellar component this time. I wasn’t observing this galaxy but using it to help locate PGC 2176488 and it popped. Looking at other reports and photos it’s tough to determine exactly what it is, but I’m leaning toward a stellar nucleus in the primary. There’s some debate about the object being overlapping galaxies or one galaxy with several prominent HII regions.
PGC 2176488/15.8 showed itself in averted vision about 30-40% of the time. This was the last galaxy seen in the session and Charlotte was beginning to assert itself. Around 6’ east of the half-circle of galaxies mentioned above, it was an even fuzzy dot around 0.4’ in size.
PGC 58319/15.6 was much easier to pick out as the peak of an isosceles triangle with a pair of bright stars 5’ west. Visible in AV around 60%, it did show a slightly brighter area in the center of a 0.4’ halo.
Abell 2199, central and southwest field of view
Field = 30’
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Abell 2199, at a mean distance of 410 MLY, is home to at least 88 major galaxies and may well be over 200. It and nearby Abell 2197, with which it’s likely interacting, sit at a point where the Great Wall takes a curve 150-200 MLY further out to Abells 2151, 2147 and 2152 at the eastern end of the structure.
The cluster is dominated by NGC 6166, which is also the central member of Vorontsov-Velyaminov 364 group of interacting galaxies. The report for that galaxy and group will come after this one with its own accompanying images.
My preparation miscalculated the size of the field of view the 21mm would afford as too small. As a result, I did not look for additional galaxies beyond what I thought were the limits of the FOV. I had other charts but didn’t bring them into play. A missed opportunity, sure, but I was running out of time to get what I did get, so there’s that. One of these days I’ve got to get my math sorted.
Observing: 7/26/2025 - The night unexpectedly cleared right before it was fully dark, and the club’s star party was lightly attended affording me time on the 24” that I’m not used to having on those occasions. Transparency hovered between 9,600-10,000 ADU – the best in weeks and seeing was okay-ish at 2.5 a/sec. Very muggy and still in the 90s. SQM = 21.4.
Having observed NGC 6166 and the other galaxies of VV 364 at the heart of Abell 2199 3 days previously, the observation of the rest of the cluster moved out from that point, beginning with a small group to the south-southwest. Scanning a large and crowded field like this is all about finding marker stars to point the way to an area that contains more galaxies. Noted on the chart, then located with the 21mm @ 145x, the star patterns then allowed a shift to higher power, usually the 8mm @ 381x, but at times the addition of the 2x PowerMate @ 762x was needed to confirm smaller galaxies. Most member galaxies were very dim, and if they were of any size over 0.2’ or so were seen best with the 8mm – a real workhorse for this kind of hunting. Going back and forth between the two and/or using the 13mm @ 235x for detection was not unheard of either.
The observation took in the central and southwestern portions of the cluster.
The first to be seen was PGC 58277/15.0 just outside the VV group and forming a triangle with a pair of marker stars. A dim round halo of about 0.5’, it barely showed brightening towards the middle in averted vision. As an SBc, I’m thinking it’s a surface brightness issue as it was held direct only once or twice. Nevertheless, it was able to serve as a landmark for the two galaxies next to it.
PGC 58278/15.9 was an AV-only sighting, and a faint 2:1 slash with a PA of 345° with dimensions of 0.3’ x 0.1’. There was a suggestion of brightening towards the center.
About 0.1’ north of PGC 58277 was PGC 58276/16.8 – a featureless 0.1’ dot that was also AV only. I can’t be sure, but I believe I saw a stellar nucleus winking at the location.
Back to the south of this trio PGC 58279/15.9 continued the chain as a featureless averted vision disc of 0.2’. Pretty Deep Maps shows a distance of 517 MLY, putting it on the far edges of the cluster 100 MLY from the center, and demonstrating the three-dimensional nature of the cluster and Great Wall.
A pair of bright marker stars were well to the south in the FOV, on the “official” border of the cluster, and marked a couple small galaxy chains, of which I only observed one member. The other small grouping at the southern end of the star pair was missed due to my miscalculation of the field size, and therefore not having them marked as part of the field. Doh.
The galaxy seen to the northwest of the dimmer of the two stars was NGC 6158/14.7 which was held in direct vision perhaps 80% of the time and with a clearly brighter but non-stellar center. Slightly ovalled, it had a diameter of perhaps 0.6’. Two dimmer galaxies that flank it were not seen.
Back to the north was a distinct and helpful little triangle of stars at the end of a curve of moderately bright stars that partially surrouned the VV 364 group to the west. Near the center of the of the triangle was PGC 86299/16.5 – a tiny dot of 0.1’ with no detail. Honestly were it not positioned where it was, I doubt I would have seen it as it was AV-only less than half the time.
To the northwest of the star triangle was a shallow triangle of three galaxies, with a moderately bright star as helpful orientation. First of these seen was PGC 58213/15.7 which showed as a 2:1 oval with a brighter center – PA 315° and 0.4’ x 0.2’.
Just “below” it to the north in my view was PGC 58212/15.6 as a round 0.4’ halo with a central brightness.
And just south of the landmark star in the area was PGC 58200/16.2 which was barely made out in averted vision around a third of the time I looked at the spot but nevertheless showed some brightening at the middle.
The bright little star triangle was then used to locate PGC 58220/17.1 and PGC 2151953/17.4 just to its north, with the latter serving as the limiting magnitude for this session, without taking surface brightness into account. Both these galaxies were featureless and AV-only, 30% and 20% of the time, respectively. Both were very faint dots of 0.1’
I used NGC 6166C to locate PGC 58232/16.3. This one was particularly tough as a faint threshold star kept trying to tell me it was a stellar nucleus, but the occasional and very faint glow would not line up with it. But that was actually the confirmation I needed since the smudge persisted.
To the north of NGC 6166 – always a bright marker – were two pairs of stars of moderate brightness which served to locate at least two of a dispersed group of very faint galaxies all fainter than 17.0, save two. Further east was an area of bright stars that formed the eastern border of the grouping, but none of the galaxies that far east were seen as only a couple were in the low mag 17 range and they refused to show.
Of the two galaxies north of 6166 seen for sure, the first spotted halfway between one pair of stars and 6166 – PGC 58272/16.9, a tiny featureless dot less than 0.1’. Just to its northeast was PGC 58294/16.4 which seemed more than half a magnitude brighter but remained featureless. It might have reached 0.1’ in size.
Two galaxies further north, bracing one of the helpful star pairs were PGCs 58271/17.2 and 58273/17.2. I believe I saw them, but even with tube bumping could not get them to show themselves with any real consistency, so I’m calling them possibles. (They were confirmed on 8/29/2025)
Time for the session was running out, and there were a number of galaxies I had to let go, including at least 3 in the center of the FOV and a handful to the west for which I was not prepared due to the miscalculation of the field.
Addendum from 8/29/2025
Given the misses of the unexpected session mentioned above, another unlooked-for clear night enabled me to make up many of the oversights (and a couple in 2197). It felt very good to have the chance to do that as it was nagging me and I didn’t want to wait until next summer. Here are the additions:
Starting at the south end of the FOV, at the bright pair of stars that marks NGC 6158, I was able to pull in the small chain of 4 just to the west-northwest of the stars. Southernmost was the pair PGC 58215/PGC 2147337. PGC 58215/15.0 was seen first, and the core could be held directly for moments at a time. The full extent of the 1.0’ halo was best seen with averted vision. Looking around the galaxy a stellar point winked out periodically right where PGC 2147337/15.3 is located. Not sure that I saw a halo, but perhaps once or twice in AV. The stellar nucleus was prominent, looking like a threshold star where there isn’t one.
Just to the north is a pair of 0.5’ galaxies, whose line deviates slightly east from the one defined by the two marker stars. The first, PGC 58216/15.6 showed a brighter center, whereas PGC **58214**/15.8 just 2’ north-northeast of it was an even smudge.
To the west of this group, and barely in the FOV, was a shallow curve of three discernible galaxies, all 2:1 even smudges roughly 0.8’ x 0.3’. About 3’ or so west-northwest from the southern marker star was PGC **169658/16.2 with a PA of 340°. 4’ west of that was **PGC 3499204/16.2 with a PA of 290°, and finally 7’ further northwest was PGC **58158**/15.8 – PA 345°
About 15’ further north, at roughly the same ascension as NGC 6166 was PGC 58163/14.9, which was an averted vision object despite the brighter magnitude, but a relatively large round smudge of at least 1.5’ with a winking stellar nucleus.
7’-8’ east-northeast of that was PGC **58192**/16.3, a tiny even smudge of 0.3’ diameter and purely averted vision about half the time.
East-southeast of NGC 6166 was a galaxy I missed because it was hiding behind a label on Pretty Deep Maps (This happens with some frequency in crowded fields and can be annoying). NGC 6166 and a fairly bright star to its south form the base of a triangle for which PGC 58314/16.1 is the peak. A round AV halo of 1.0’, it did show brightening at the middle.
PGC 58255/16.6 (the faintest object for the night) sat at the end of a shallow curve of galaxies south-southeast of 6166 that was observed in the previous session. Consisting of, north to south, PGC 58276, 58277, 58278 and 58279, the curve they define pointed right at the faint galaxy which was totally an averted-vision object showing only as an even round smudge of maybe 0.2’. In photos and charts it shows a 2:1 halo but I’m sure all I was seeing was the core.
Around 18’ north of NGC 6166 was bright HIP 80692/8.8, just outside the field of view. It marks two small chains of galaxies which both curve south-southeast away from it and roughly halfway to NGC 6166. The easternmost of these was not observed as too close to the edge of the FOV and best included with the group of galaxies outside the cluster boundary further east. Of the little chain to the west of that, 3 galaxies were just over mag 16, with the other 5 too faint to pull in. The three seen were all 2:1 AV smudges of 0.5’ x 0.3’ and were confirmed by using the 2x PowerMate with the 8mm Ethos for 762x. HIP 80692 forms a pair with a dimmer star 4’ to its southwest. That star marked the start of the chain with PGC 58242/16.0 (PA 90°) which also showed brightening towards the center. 1’ northwest was PGC 140626/16.4 (PA 330°), and another 2’ northwest was PGC 2154233/16.1 (PA 310°). The halos of these two were visible in AV 40-50% of the time, but both showed stellar nuclei that winked out regularly.
Finally, also barely outside the field of view, 8’ east-southeast of HIP 80692, sat UGC** **10404/VV 1812 at mag 15.1. Being a VV object I really wanted to “cheat” it into the field as it was so close with nothing significant or observable near it to warrant a separate field observation. (Not sure why it’s in the catalogue as there’s no interacting partner). An Sb with apparently low surface brightness, it was a fairly large but very dim 1.5’ even smudge seen in averted vision.
Vorontsov-Velyaminov 364 and NGC 6166 at core of Abell 2199
Field = 10’
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At the heart of the rich cluster Abell 2199 is the very large elliptical galaxy NGC 6166, host to one of the largest known supermassive central black holes at 30 billion solar masses and the largest globular cluster system known at 39,000, likely due to several galactic mergers in the past. It would seem that process is still ongoing as several smaller galaxies are within its gravitational influence. That’s also what places the galaxy in the Vorontsov-Velyaminov catalogue. The galaxy is 490 MLY distant and is one of the brightest known in terms of x-ray emissions.
The plan for the night’s session, based on a favorable viewing forecast, was to pick up a large chunk of Abell 2199 as the last observation was over 3 years previous, and I was hoping to update and see more galaxies than the previous view. Alas, the forecast did not hold, and clouds threatened to move in, leaving me time only for the central portion around NGC 6166. At least I could make a try for the small crowd of neighboring galaxies that make up VV 364, as well as 6166’s double core from overlapping NGC 6166B. At mag. 17.6, I was not hopeful for the other overlapping core of PGC 58257, especially within the background glow of 6166’s core region. Sure enough it eluded me, nor did I have the time to wait for it.
Observing: 7/23/2025 Transparency started off okay at 8,200 ADU but would only linger there for a brief time before trending downward in advance of the clouds approaching from the southeast. Fortunately seeing stayed under 2.0 a/sec. SQM reading was 21.4. I started out using a 40mm EP @ 76x for the widest field, but 6166 was only a suggestion, whereas it was bright in the 21mm TV Ethos @145x. With the clouds rapidly approaching I quickly decided to go for just the V-V group, so in went the 8mm coupled to the 2x PowerMate for 762x.
NGC 6166 was a bright 1.5:1 oval with a long axis of 1.2’ – PA 50°- and short axis of 0.5’. It took a few minutes for 6166B’s core to show against the glow, but it finally did with averted vision – about 0.1’ southeast of 6166’s core. I thought I had it directly once. 6166 was very easy to hold in direct vision. The other galaxies were all seen with averted vision and looked like a group of floaters except that they moved with the tube and persisted in their location. Time did not permit a longer observation to see if any could be seen directly and/or if more detail could be made out with further AV views.
0.2’ off the southwest tip of 6166 was the tiny glow of PGC 58261/16.0, itself a round glow of only 0.1’, likely only the core.
5.0’ further southwest was the brighter 0.3’ but featureless glow of PGC 58262/15.6.
PGC 58275/16.0 sat 1.5’ south of NGC 6166’s southwest tip and showed much like PGC 58261 – a tiny glow of 0.1’, likely only the core as transparency was dropping, making halos difficult.
NGC 6166A/15.6 was 1.2’ west of its larger companion, and showed only as a round, featureless glow of perhaps 0.2’
NGC 6166C/15.3 was around 2.0’ northwest of NGC 6166, presenting as an even, round glow of 0.4’
Tiny PGC 58253/16.9 right next to 6166’s western side was not seen, providing a rough limiting magnitude for transparency. Surface brightness was unavailable.
It was disappointing to have the clouds move in much earlier than expected. They didn’t even show up on GOES before the 30-minute drive to GHRO. The take-away for me, though, was being able to capture 7 galaxies (counting the core of 6166B) when three years ago I found a total of 7 in a much wider field, and only one of the galaxies close by 6166. That’s one outcome I was hoping for. The rest of Abell 2199 will have to wait on clearer skies.
I hated the tyranny of the approaching clouds not allowing a more extensive look at the galaxies. So even though I’m confident of these sightings, I didn’t get the “ironclad” confirmation I usually require of myself. That said, I did the sketch anyway to preserve the experience and check against a future observation. The last time I had something to sketch was over a month ago.
Addendum from 7/26/2025:
Only 5 visitors on this star party night, giving me time to revisit and confirm the previous sightings. Feel much better about it now. T was much improved, hovering between 9,600 -10,000 ADU, as opposed to 8,200 and dropping, but seeing was a bit worse at 2.5-3.0 a/sec. SQM was consistent with the last several sessions at 21.4.
The “larger” members of VV 364 – NGC 6166A and C plus PGC 58262 showed brighter centers this time as did PGC 58299/15.9 which was added at the end of the night’s session. The 0.3’ halo was best seen in AV and a stellar core winked in and out.
PGC 58274/17.0 was also seen for the first time, but only its stellar core. I thought I was seeing PGC 58275 again at first but then saw the two together. The chart showed no star at that location.
Finally, after some dedicated averted looking, PGC 58253/16.9 revealed itself as a 0.1’ glow just outside the west side of 6166’s halo.
Still no joy on the “third core” in 6166, but a very satisfying observation. Make that 10 galaxies in VV 364. I think that’s the most galaxies I’ve seen in such a small field of view (7.8’ @762x). Now to amend the sketch…
Abell 2151 (Western half) in Hercules
Field = 21’
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Finally, after 2 years of looking, this distant portion of the Great Wall of galaxies showed itself. I think it took that long for my observing ability to develop to the point that I could detect these tiny, faint galaxies. Abell 2151 is also known as the Hercules Cluster (not to be confused with M13) and makes up the heart of the Hercules Supercluster.
This group ranges from 465 to 600 light years distant, so its 200-plus galaxies are small and quite faint, with the visual magnitudes of those seen ranging from 14.3 to 15.4. With a surprising number of spiral galaxies – over half – low SB is the rule. The cluster is also rather chaotic, with a lot of interaction, so a number of Arp and VV objects populate this group. AOC 2151 is also unusual in that it is not dominated by a giant elliptical galaxy. It’s believed to be a young cluster and an example of what galaxy clusters may have looked like in the early universe.
Abell 2151 also stands out as particularly confusing as to galaxy identification. Steve Gottlieb mentions in his tour of this area (S&T July 2016) that amateur software is often based on past NGC imprecise coordinates, citing PGC 57073 and NGC 6054 as examples. I spent much time trying to align my observation with his notes, as well as other “amateur software” but I’m not nearly as confident as with the other clusters. Frustrating.
Observing: 6/7/2024 Clear, calm and mild conditions certainly helped with comfort, and contributed to some of the most transparent skies I’ve ever seen at 11,400 ADU. Seeing was between 2.5 and 3.0 a/sec with an SQM reading of 20.66. The starfield was confirmed at 145x, and the galaxies began to suggest at 235x, so that was used for the field. HD 144149 at mag. 6.8 was a great guide as the westernmost galaxies are only a few arc minutes to the east, although it helped to keep it out of the FOV for the glare. The somewhat poor seeing limited useful magnification to 381x using the 8mm. Looking for more details using the 2x PowerMate @ 762x was so much mush. That was disappointing as it wasn’t possible to distinguish individual cores with the several galaxies that overlap one another in this cluster. For the most part those objects appeared as one extended smudge.
3 sub-groups were seen, the westernmost associated with NGC 6041, the next to the east with NGC 6047 and an overlapped group of three centered on NGC 6050. Only 6041 and 6047 could be held directly and that only for moments at irregular intervals.
6041 (Vorontsov-Velyaminov 213) was first seen. The core of 6041B was not discernible due to the poor seeing. It appeared nearly round with only the slightest hint of brightening towards the middle. Just to the south is a little kite-shaped group of 4 stars, with the top two pointing right at 6041.
Just above those stars and slightly north is 6042 (mistakenly labelled 6039 in PDM), which was seen next. Round and small, it showed no brightening at the center, but really persisted in AV.
NGC 6040, also Arp 122 with UGC 10145, was harder to see even though it has a v mag like 6041’s. It presented as a 3:1 slash, enlarged at the southern end. That thicker “bump” I believe to be the UGC galaxy at v mag 15.3. As with 6041, the individual cores were not seen.
To the east of 6041 a trio of stars formed a flattened triangle. North of that asterism was a fainter pair of stars forming an east-west line. Next to the western star a smudge persisted and at times was held directly. That was 6047, a 2:1 oval with a barely discernible brighter middle, that at times flashed almost stellar.
Just to the northeast was 6045/Arp 71. An elongated slash at maybe 4:1, the warped ends of this edge-on spiral that account for the Arp status could not be made out. Maybe with better seeing and the 2x, but not tonight. Sigh.
Just to the northwest, and near a pair of bright stars was 6043. A tough one to make out, it showed in AV only intermittently. 6043B that overlaps it was not distinguished from the general glow.
The last group seen consists of 3 overlapping galaxies that make up Arp 272 – NGC 6050, IC 1179 and **PGC **84722. All that could be made out was a round AV smudge. Again, better seeing may have allowed me to split the cores, but that wasn’t the case.
Also hoping for better seeing at a future observation to better discern the details of the Arp objects and other overlapping members. Wouldn’t mind finding more members as well. (Did not yet know to use the 21mm for the field of view, but the 8mm for detecting and observing individual galaxies)
Addendum from 9/13/2025:
This was the last shot at Abell 2151 for the year, and chance to update last year’s observation. It was fully dark at 8:56 and a half hour later the Lancaster SC light dome precluded any further viewing in this part of Hercules. The first 30 minutes, however, enabled me to see some details and galaxies not seen last year. The 8mm TV Ethos @ 381x and 2x TV PowerMate @ 762x were used to observe individual galaxies.
NGC 6041 was much brighter this time, even though transparency was not as good (8,600 ADU). Seeing was improved, at times less than 2.0 a/sec. Not only was the core more distinct and the halo larger, but most importantly the second core of NGC **6041B**/16.5 was visible in averted vision. At first looking like 6041’s core was elongated, in moments of better seeing the two were distinct. The interacting pair is 213 in the Vorontsov-Velyaminov catalogue. IC 1170/17.4 to the northwest was not seen.
Arp 122, comprised of NGC 6040 and UGC 10145 (6040B) was also much brighter, being a threshold observation last year with neither core seen. This time both cores were visible, with UBC 10145’s appearing stellar.
A distinct “L” of three stars marked 6041 and 6042, which also led to a threshold sighting of PGC **1538875**/16.3 perhaps 3’ south-southeast of 6042. An even round smudge of 0.8’, it was seen in averted vision only perhaps 50% of the time.
Further south for another 15’ PGC **84715**/16.0 was seen as the twin of 1538875.
20+’ north of the L-star arrangement was PGC **84714**/16.2 – A round featureless halo of perhaps 1.0’. No detail was seen given its low SB as a spiral and the fact that the cluster was setting into the western light dome.
Abell 2151, eastern portion
Field = 21’
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This observation completed my look at Abell 2151 – for now. A number of members that I would have hoped to have seen, as well as details from the previous galaxies observed in the western portion were not seen due to less-than-ideal conditions. Still, seeing anything that far out – 500-600 million light years – is inspiring.
Observing: 6/25/2024 The clouds continued to threaten until just before true dark. But even though they were mostly gone by then and later gone altogether, transparency never recovered, staying at or below 7,500 ADU, which I’m translating to 2-3/5. Seeing was passable at 2.5 a/sec even though a breeze would kick up now and then. SQM reading was a disappointing 20.36. So, conditions were not ideal, but the southeast is listed as humid-subtropical for a reason.
Previously observing the western portion of Abell 2151 really helped with orientation as the star field was like a known street map. I was able to use HD 144149 at mag. 6.8 as the first landmark, then head east for the shallow triangle that helps to mark the southern boundary of the central western part of the cluster. Centering on the bright star just above (east) of Arp 272 [easternmost member seen in last observation – west), I switched to the 8mm for 381x. The FOV enabled me to get the southern and northern boundaries of the group, barely.
IC 1193 showed first after several minutes and was easily the brightest even at vmag 15.5. It was held directly for several moments at a time and showed a distinct brightening at the center, at times almost stellar, with a slightly oval halo.
Three galaxies form a line running roughly north to south, with each about the same distance from one another.
IC 1183/15.3 was marked by the bright star in the center of the FOV and showed as a 2:1 oval with no detail. Any brightening at the core was washed out by the nearby star and/or the sky conditions.
PGC 57060/15.9 lay north-norteast of IC 1183, halfway to the edge of the FOV. It took some time to smoke out but persisted as moderately bright once located. It was easy to look away and come back to it.
IC 1185/14.9** **was equidistant to the south, showing only as a featureless smudge
NGC** 6054** appeared south of the bright near the center of the FOV and was difficult to bring in likely due to the same restrictions imposed on IC 1183. It was an AV smudge only with no details or very discernible shape, really.
PGC 57073/15.9 formed a triangle with the previous two galaxies, with the bright star in the center. It presented as a round smudge visible in AV most of the time, and direct once or twice. It did show some brightening in the middle.
Arp 172 – IC 1181/1178 (15.0 and 15.9 respectively) are at the southern boundary of Abell 2151 and just inside the FOV. Again, conditions prevented me from seeing anything more than a combined smudge with no detail, particularly separate cores.
Further north is what I believe is** PGC 57055** **(**2MFGC 12921), which appeared as a threshold object, a featureless 2:1 smudge.
Near the western edge of the FOV was Arp 272 **- **NGC 6050/15.4** and NGC 6050B/16.1 (or NGC 6050 and IC 1179 and PGC 84722 **), the easternmost object seen in my observation of the western part of Abell 2151 a couple weeks previously and described in the previous report.
Much like the observation of the western half of the cluster, a bit disappointing in that I had hoped to see more members as well as more detail. But I am happy to have seen what I did given the less-than-ideal conditions. Enough of the cluster was seen to consider it observed, for now, at least. Abell 2151 very much needs to be revisited not only to pull in more member galaxies, and hopefully more details, but also to make sure of placement.
Abell 2147 galaxy cluster in Hercules (central portion)
Field = 30’
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Abell 2147, overlapping the border of Hercules and Serpens Caput, along with 2152 (in Hercules), was added to those known to be associated with the CfA2 Wall once redshift data determined they are associated with the structure. The group also contains three Vorontsov-Velyaminov interacting pairs (90, 91 and 92), as well as the Arp 324 chain of galaxies. Both the Arp group and the Abell cluster are dominated by central member UGC 10143, a giant elliptical shining at mag. 14.2 and hosting tens of thousands of globular clusters. Other than its Arp companion at the southern end of the chain – PGC 2790838 at mag. 15, most of the rest are in the 16s and 17s magnitude.
Observing: 5/22/2025 2 months to the day since my last observation. Sigh. But finally, the clouds parted, and the moon was gone. Armed with new lenses after cataract surgery, I swung the 24 into Hercules for the central portion of Abell 2147. Observing all the group will take 3 fields of view. The central one was taken first as it’s the more populated and brighter. Seeing was not great at 3.0 a/sec, but transparency was surprisingly good – 10,000 ADU and better at times – despite the sparse peppering of small clouds. SQM read 21.4. This is a very faint cluster as noted above given its vast distance, so most of the galaxies seen were primarily averted-vision objects. Only UGC 10143, PGC 2790838 and VV 90’s pair could be held in direct vision for any length of time.
At the center of this semi-rich cluster – class I (50-79 members) are the six galaxies of Arp **324, **really the showpiece of this grouping. Let’s start there:
UGC 10143/14.2 is a giant 2:1 bright, direct vision elliptical of 4’ by 2’ with a PA of 70°. Sitting at the northern tip of the Arp chain, the halo was of uniform brightness with a nearly stellar nucleus.
Moving south in the chain, PGC** 1497312**/17.1 was a very faint nondescript round smudge of maybe 0.1’ only 1.0’ south-southwest of UGC 10143. It was never held directly, but AV revealed a small round brighter object barely separated from the UGC’s halo. The galaxy was seen perhaps 20% of the time.
In the center of the chain sits PGC 56777/15.1, a dim 2.5’ round halo with a suggestion of brightening toward the center. It was held directly for moments and in averted vision maybe 70% of the time.
PGC 401984/16.3** **was next and much like PGC 1497312 was a 1’ round halo barely discernible from its larger companion to the south. Slightly brighter than PGC 1497312, it was seen only in averted vision perhaps 50% of the time.
The other bright member of the group, PGC 2790838/15.0, is an E-SO elliptical, with a 3.5’ round halo that was clearly brighter in the center with a nearly stellar nucleus. It was a direct vision object, the extent of which was best seen in AV. It was the first galaxy seen in the observation, and although at 15.0 it’s nearly a magnitude dimmer than UGC 10143, its better surface brightness (22.3 vs. 23.6) made it the brightest and easiest member to hold. It is marked by the brightest star in the FOV around 15’ to its southeast. A closer but dimmer companion star helped it to point almost right at the galaxy.
Southernmost in the chain was the edge-on Sc spiral PGC 56770/15.6, a 4:1 slash of 3.5’ by 0.8’ and PA of 290°. Curiously, though AV most of the time, the galaxy would flash out as a streak periodically at which time it could held in direct vision. It flashed six or so times over the course of the observation.
The three V-V interacting pairs were just inside the southern edge of the FOV. VV 92’s members come in at 16.8 and 18.0 magnitude respectively. They were not seen, despite hopes for a glimpse of one nucleus.
VV 90 consists of IC 1165/15.2 and PGC 56768/15.6. Both were round halos with central cores visible. IC 1165 was 1.3’ and bright enough to hold directly 70% of the time or better. PGC 56768’s halo was smaller at 1.0’ and AV only, almost touching its companion. Its core, however, was held in direct vision for brief moments. It is well-marked by four stars to the southeast like the tail and wings of Cygnus, for which VV 90 forms the head.
About 7’ southwest of VV 90 is VV 91 – PGCs 56765/16.4** and 1490719**/17.8. Its two nuclei appeared as two tiny barely resolved stars in a 2:1 halo of 1’ by 0.5’. The latter galaxy’s halo looked more like a threshold star off its companion’s northeast tip. At magnitude 17.8 I think this is the dimmest galaxy I’ve seen, and I doubt I would have discerned it but for that stellar nucleus. These two were visible in averted vision only and that for maybe 30% of the time. The pair can be located within the four stars mentioned above as a mini-Cygnus. Seen that way, VV 91 appears 2’ north of the star that would be Sadr/γ Cygni.
The rest of the galaxies in this field of view were elusive and seen in averted vision. None were bright enough to be held directly. Unless otherwise noted, these galaxies were dim, round smudges of 1.0’ or less with no central brightening or stellar nuclei. Most were seen in AV for 50% of the time or less. Knowing the starfield is a must.
The exception to the description above was PGC 568838/15.2 near the eastern edge of the FOV. A 2:1 oval with only the barest hint of central brightening, it measured 2’ by 1’ with a PA of 340°. It was marked by a pair of stars – the brighter to the southeast.
6’ to the north of the Arp 324 chain was a pair of galaxies that nearly overlap, but I could not determine if they are interacting or just an optical pair. Consisting of PGCs 1498789/16.6** and 1498896**/17.0, they appeared much like VV 91.
Halfway between VV 90 and PGC 56838 was PGC 100398/15.6. It would likely have been overlooked but for its placement next to a rather bright star that almost washes it out. It formed a triangle with that star and a fainter one to the galaxy’s north.
Due east of Arp 324 is a sparsely populated and broad area of seven tiny galaxies, of which I was able to discern 3 – PGCs 56830/16.3, 3858169/16.6 and 1496494/16.6. The latter is 2.5’ southeast of the only star visible in that quadrant.
If the bright star and its companion mentioned above, near the center of the FOV and marking Arp 324, are two points of a tight triangle, PGC 1495423/16.3 was the third. 6’ east-southeast of that bright star was PGC 1494672/16.7**. **These two were a real challenge.
The final galaxies seen were in the central west-northwestern quadrant of the FOV. There is a mini-cluster of 10 galaxies, of which I saw three, all just above 16th magnitude – PGCs 56741/16.0, 1494143/16.3 and 1494348/16.3.
My viewing session began before true dark at 10:04 PM, taking down the starfield as it came into view. I had 1.25 hours with which to work and the central FOV of Abell 2147 took all of it. Even then it felt overly-brief as many members of the group took much of that time just to puff into view. I know time is limited before Hercules disappears, but I don’t want to rush this. To me it’s worth spending the time to snag as many galaxies in each FOV as I can, knowing that I’m not seeing a tithe of what makes up this mammoth structure.
Galaxies in Hercules Supercluster between Abell 2152 and 2147
Field = 30’
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This grouping does not have an official designation but does contain 2 Vorontsov-Velyaminov pairs. It’s included in the project as a bridge between two Abell Clusters – 2152 to the east-northeast, and the larger 2147 to the southwest. The galaxies in this region are at similar distances/redshifts with those of 2147 and the western portion of 2152 (450 - 600 MLY) such that the CfA2 Great Wall can be contemplated in three dimensions at this juncture, bending further away as it winds east. Note that the eastern portion of 2152 is populated with galaxies at distances of 630-680 MLY, and those in the central portion of the Wall, in Abell 1367, the Leo Cluster are at distances of 275 – 340 MLY. The Coma cluster/Abell 1656, further east of Leo, has galaxies in the 350 – 400 MLY range as though reaching for the more distant groupings in Hercules. In all the groups, there are also members 100 MLY closer than the average, showing that the Wall is wide as well as long. The width of the wall is edge-on to us. The strand of galaxies in this view stretched northeast to northwest from one end of the field of view to the other, even leaving a couple out at either end, but only occupied half of the northwest to southeast axis, showcasing CfA2’s thin third dimension.
This particular area is not as densely populated as the bordering Abell clusters; hence these galaxies are not included in either one. As with those other groupings, this area has a good share of galaxies well into the magnitude 17 range, so I didn’t hold out much hope for those, nor as big a haul as with the fields of view that take in 2147 and 2152 proper.
Observing: 6/23/2025 The conditions started to bounce around a bit by this time, with transparency starting a slow trend downward from 8,200 ADU. In addition to that, fatigue during this all-nighter was beginning to set in as well, making it harder to maintain concentration for extended periods. Given both those realities I was satisfied to come away with what I did. The mugginess was not only tiring but was too much for the hood even using the snorkel. I resorted to cupping my hands around the eyepiece to shield stray light as much as possible, but that’s just not as effective as a hood that covers everything. No doubt some of the high 16 to low 17 magnitude galaxies I thought I might see were lost due to the lack of contrast as a result. Thankfully seeing was good at 1.7 a/sec and the SQM was steady at 21.4.
The northeastern edge of the field of view featured three bright stars in a shallow scalene triangle. The tip of the triangle is HIP 78560, mag. 9.9. The triangle also served as a great marker for the galaxies at that end. Between the triangle and the edge of the field of view, a galaxy Aladin designates as 2MASX J16022972+1624109** **barely crept into view. It wasn’t quite up to direct vision but was obvious in AV as a round halo of maybe 1.0’ with a gradually brighter center. PDM identifies the galaxy as PGC 1507961/15.8 which Aladin places to the west of VV 1787, and seemingly part of VV 1786 as the partner of PGC 1506935 (two paragraphs below) that I did not see. The RA/DEC coordinates show Aladin to be the correct source.
I’ll be honest that I didn’t spend a lot of time on it, as my eye kept getting dragged over to VV 1787 in the center of the triangle and only 4’ from HIP 78560. Fortunately that star was not so bright that it washed out the two galaxies. I really enjoy finding VV pairs, and there were two right next to each other, with VV 1786 a little further west, just outside the curve of the triangle. VV 1787 consists of UGC 10144/14.2 and PGC 56786/15.5. Boy, compared to what I’d been viewing the past month, magnitude 14.2 was like a floodlight! No trouble holding the galaxy in direct vision. UGC 10144 is a curiously elongated elliptical galaxy and showed as a 3:1 oval of 2.0’ x 0.8’, PA 345°. The core was bright at the center. Its partner PGC 56786, on the other hand, was a bit tougher to tease out, but was eventually held directly for 50% of the time. The first hint of its presence was a winking stellar core. Round and small, I put it at 0.8’ diameter. A dim threshold star winked out periodically between the two galaxies.
Due west of this pair was VV 1786, of which I only saw the larger and brighter member – PGC 1506935/16.7. There’s another small galaxy of 16.7 magnitude nearby, and at first it was hard to determine which one I was seeing, but looking for a while settled the location. Much of the difficulty came from the galaxy being so dim that it was strictly an averted vision object, and that for maybe 20-30% of the time. The faint smudge moved with the starfield when I bumped the tube. Its companion, PGC 150706/17.4 was not seen. It’s listed at around 80 LY closer, so either that number is in error or the two aren’t in fact interacting. From the note above, Aladin designates this galaxy as PGC 1507961.
North of the two VV pairs is a small chain of maybe 8 galaxies, but only three were large and bright enough to be seen, even in averted vision. PGC 56776/15.5 was easily the brightest, and the other two came in at 15.6. Seen best in averted vision, it was held direct about half the time. This SBb galaxy is almost twice the size of the other two, with a round halo of about 1.2’ and a stellar nucleus. It’s also well marked by the northernmost star in the bright triangle mentioned in the beginning of the observation. Northwest from that star and almost for the same distance as it is from HIP 78560 is another star that continues the shallow curve. Not as bright as the other three, it’s still prominent and marked the other two galaxies visible in the area – PGC 56760/15.6 and PGC 142837/15.6, which braced the star at equal distance to its southeast and northwest respectively. Both were small round, featureless AV smudges of maybe 0.6’, although I got the impression that PGC 142837 was slightly larger than its companion.
Further to the west, about the same distance as the two previously mentioned stars are from one another, was a prominent curve of three stars, with the westernmost brighter than the other two. The curve actually continued east with a far more dim but steady star at some remove from the last two. The curve and the final star were helpful markers for two additional galaxies that certainly needed the help. PGC 1508620/15.7 popped in averted vision as the tip of a triangle whose base was formed by the third and fourth stars in the curve just mentioned. Once spotted it persisted but showed no detail and couldn’t quite be seen directly. PGC 1507723/16.6 forms a right triangle with the two stars that helped with PGC 1508620, and it sat equidistant from the last star as that companion galaxy. It was held in averted vision only 50% of the time and was very much a threshold observation. It was a small smudge of uniform brightness.
Further west beyond the brightest star in the curve is a nice grouping of galaxies, but I saw none of them as they are all well beyond 17th magnitude and very tiny indeed.
South-southwest from the same bright star (westernmost in the curve) is a prominent pair of stars of the same magnitude as the second and third stars in the curve of three. Perhaps 15’ to the northwest of the pair of stars is a pair of galaxies near the western edge of the field. PGC 56666/15.3 was first detected in AV but once seen was held directly with little problem. The full 2:1 halo of 1.5’ x 0.7’/PA 295° was best seen in averted vision, but the central brightening was always there. Less than 1.0’ separates it from PGC 56667/15.9 to the north. This galaxy appeared smaller and round, maybe 0.8’, but showed only the faintest hint of brightening towards the center. It was seen directly a handful of times, but fairly consistently in AV, maybe 80%.
The last two galaxies seen in the field were back to the east of this pair of galaxies and were a challenge in that the star field in the area is both sparce and dim. The first of the two seen was UGC 10134/15.4, spotted by scanning around an area to the east of the pair of stars that marked PGCs 56666/56667 until it puffed into averted vision as a round smudge of 1.5’. A barred spiral with surface brightness of 23, it revealed no details in its uniform brightness. The last galaxy to be seen was further east and helped by a brace of dim stars that took some time to hold consistently. That was PGC 142836/16.3. Reluctant to show itself, it finally puffed into view but revealed no detail. Maybe 0.6’, it was a minimal AV-only sighting, maybe 30-40% of the time.
This area seemed to be a lot more work for not as many galaxies. Maybe I was just tired. That in itself was a new experience. I’m never ready to stop, and I didn’t after this, going on to take down the star fields for future re-observations (hopefully) of Abells 2197 and 2199. By then the moon was on the rise and I was done. Seeing the two Vorontsov-Velyaminov pairs was a treat, though, as was making the bridge between the last two Abell groups in the Great Wall. Nearly complete!
Abell 2152 west - galaxy cluster in Hercules
Field = 30’
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This target was a milestone in the CfA2 Great Wall project, as it’s the final Abell group I needed to observe to have seen all seven. That said, there’s still a long way to go as some need revisiting (Now that I know what I’m doing) and others are not complete. Some, like this one, are large enough that it takes a couple fields of view to include all of the cluster within the official boundaries, and also that I’m including more if there are significant numbers of galaxies outside the group boundaries with the same redshift. AOCs 2147 and 2152 are close to one another on the sky – separated by less than 2 degrees – but their centers are over 100 MLY from one another, with 2147 at an average of 500 MLY and 2152 at well over 600 MLY. In the eyepiece that makes 2152 probably the most difficult of the seven to observe. It’s also a bit spread out as far as non-members in the same redshift neighborhood, so it took 2 fields of view to take it in. It’s only a bit more sparsely populated than its close neighbor but seems more so as the bulk of the galaxies in the group are mag 17 and higher.
This observation takes in the western half of 2152’s central region, plus a grouping of galaxies further west from the cluster boundary, but east of the observation above.
I’d visited Abell 2152 a couple days previously, but realized I’d miscalculated the field of view. Fortunately, it was a miscalculation that allowed a wider view than I’d anticipated. The intervening days also allowed me to become more familiar with the star field. In preparation for these observations, I’ve used screen shots of Pretty Deep Map files, showing the extent of the area I wanted to observe – often far more extensive than one field of view. So, I would also take screen shots that zoomed in on smaller sections for further guidance with which to hunt down individual galaxies with the higher power eyepieces. That was particularly helpful for Abell 1252. Being the furthest distance away of all the Abells in the CfA2 Great Wall, its galaxies are both very faint and very small to tiny, and therefore most are not very visible, if at all, in the 21mm/145x. Something was usually made out at 235x with the 13mm and then investigated with the 8mm at 381x and sometimes with the 2x PowerMate for 762x. The western half of the cluster and those further west are on average around 100 MLY closer than members in the central region and eastern extension. Contemplating that while observing and looking at the drawings gives a real sense of how the Great Wall wanders in three dimensions.
Observing: 6/22/2025 Transparency was so-so at just over 8,200 ADU, bouncing around a little. Seeing held rather steady at 2.2 a/sec and the SQM readings averaged 21.4. Clear and calm, it was also muggy in the extreme. Happily, the optics didn’t fog up, maybe just a little at times. However, I felt wet all night which got to be a drain, as was gazing that deep and concentrating nearly non-stop for 5 hours. I’m hardly the college kid I was, pulling all-nighters when a paper was due. I was almost glad to see the moon coming up!
Easily the brightest member in this grouping was PGC 56872 at mag 14.6 – a veritable beacon in a field that exemplifies “faint fuzzy”. Visible directly even at 145x, it was at the far western end of a group of galaxies extending in that direction from the “official” cluster, and close to the western edge of the FOV. It was also one of the few that showed significant extension, meaning it must be a monster to be that large at over 550 MLY. Easily held in direct vision, averted showed greater extent to the halo, say 1.5’ x 1.0’ with a PA of 290°. The galaxy brightened to the middle in a slightly elongated core, punctuated by brighter, almost stellar nucleus. Except where noted, other galaxies were round, dim, uniform AV smudges of 1.0’ or less.
Just west of a shallow arc of 4 stars to the east of PGC 56872 was a small grouping of galaxies, four of which looked possible. I saw three, finally giving up on the fourth in the interests of time, but only after repeated looks. About halfway between the arc of stars and PGC 56872 was PGC 56886, somewhat obvious at 15.8. Brighter at the center, it also displayed a winking nucleus. It was held directly perhaps 50-60% of the time. Just to its east-northeast was PGC 2832035 at mag 16.4. Due south of these two near the edge of the FOV was PGC 1504900/16.7. It was seen in averted vision 30-40% of the time. The galaxy not seen was PGC 1505972/16.9 bordering PGC 56886 to its south.
To the north of the previous group, and near the edge of the FOV sat PGC 1509676/16.0, an AV smudge 50% of the time that could be held direct for moments. Being at the center of a loose grouping of stars helped with locating it. A uniform 2:1 oval smudge with a PA of 20°.
On the eastern side of the shallow arc of stars, and about the same distance from it as the previous group was to the west is another grouping of which I only located two. All but one are in the mag 17+ range. The brightest of these was PGC 56896/15.8 which was seen directly at about 30% of the time but consistently in averted vision. It brightened to the middle with an occasionally winking nucleus. (That phenomenon always amazes me with these very distant galaxies.) Maybe 2’ south sat PGC 1506589/17.0, a tiny and AV only smudge.
Well to the northeast, and 2-3’ southwest of a bright pair of stars near the northern edge of the FOV was PGC 3858617/16.6, alone in one of the sparser portions of the area. It was a featureless 2:1 smudge, PA 45°. To its southeast is an easily seen star, and the same distance to the east was PGC 1509294/16.4, a 3:1 uniform and elongated oval. AV only, it had a PA of 300°.
Further to the east and crossing into the proper boundary of Abell 1252 is a fairly dense grouping of galaxies in the magnitude 15-16+ range. These are clearly marked by a scalene triangle of very bright stars that can be seen well before dark.
Moving east into that area, the first galaxy encountered was PGC 56966/15.6, a slightly ovalled 1.2’ halo that brightened to the middle and with a stellar nucleus. Perhaps 3’ southeast sat PGC 56965/16.5, a tiny, 8.0’ featureless smudge seen in averted vision maybe 50% of the time.
Further southeast and popping by comparison was PGC 56975/15.5. Held directly much of the time, it was a 1.5’ round halo that brightened to the middle but did not show a distinct core or nucleus.
Keeping PGC 56966 as an anchor for this region, eight galaxies were visible to the northeast, between it and the triangle of bright stars, all but two in the magnitude 16 range.
A very dim star sat 2-3’ northeast of PGC 56966, and the same distance further northeast sat a pair of galaxies – PGC 3858852/16.3 and PGC 56984/16.6. Only the latter showed any detail, with a slight brightening towards the center. Both of these were round and about 1.0‘ in size. Due east of those two PGC 3858928 barely showed itself in averted vision at 16.9. The same was true for PGC 1511373, a tiny smudge at magnitude 17.0. Made sure it repeated at least three times in AV, my criteria for averted imagination, and it moved along with the starfield when I bumped the tube. The observation then sealed itself when a stellar nucleus began winking in and out. All three of these were very small, in the range of 1.0’ or less.
Northwest of that one, PGC 57004 **almost blazed at mag 15.3. It’s also nicely marked when seen as the fourth member of a curve with three stars. It showed as a 1.5’ round halo with a brighter middle. Making a scalene triangle between it and PGC 1511373 was **PGC 1511865/16.5. AV only showed as a featureless 1.2’ round smudge about 40-50% of the time.
Just to the east and nearing the eastern end of the FOV sat the northernmost star of the bright triangle of stars mentioned at the beginning. The final two galaxies in this field sat equidistant to the north and south of it, both at magnitude 16.2 and dimensions of 1.3’. To the south of the star was PGC 1511341, a roundish halo with no features and mostly AV but consistent. To the north sat PGC 1512728, a slightly elongated and featureless smudge that was harder to acquire and hold than its partner to the south. At an estimated distance of 681 MLY, it was tied with a galaxy in the eastern half of the cluster for the furthest member seen in CfA2.
Just sneaking into the field of view southeast of the triangle of stars is the westernmost of a pair of galaxies that make up UGC 10187 at the heart of the cluster. That pair will be described in the report dealing with the eastern half of the cluster and the galaxies to the south and east.
Looking back at the labelled drawing strongly reinforces the idea of CfA2 as a filament wandering across the night sky. Fantastic.
Abell 2152 east - galaxy cluster in Hercules
Field = 30’
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Abell 2152 is the eastern terminus of CfA2, and this field takes in the farthest east and most distant portion of it. This half of the cluster is, on average, more distant than the western half by nearly 100 MLY. AOC 2152 also a bimodal cluster, in that it’s two clusters optically aligned, with the further one 3x further out than the nearer portion that’s part of the Hercules Supercluster. In fact a small triplet of galaxies just to the east of the cluster’s center @ UGC 10187 is listed in Pretty Deep Maps as 2.02 billion light-years distant! I saw one of the three – PGC 1508574. It’s listed at magnitude 16.8 and had some dimension – 0.5 x 0.3’ – despite how incredibly far away it is. Try to imagine the size and brightness of this galaxy to have apparent size and be that luminous at that distance. But here’s where the bimodal nature of AOC 2152 comes into play. PGC 1508574 was visible because it’s being gravitationally lensed by the foreground cluster. Abell 2152 is the nearest gravity well known to us that’s lensed a more distant object.
Observing: 6/23/2025 As with the previous observation, transparency was so-so at just over 8,200 ADU, bouncing around a little. Seeing held rather steady at 2.2 a/sec and the SQM readings averaged 21.4. The sky stayed clear and calm, but unfortunately still just as muggy. The first observation of the western half of the cluster took around 2 hours and this one around 90 minutes. The field of view overlaps that of the western half of the cluster right at the prominent scalene triangle of bright stars near the cluster center.
Starting from western edge of the FOV, and the triangle are two galaxies also seen and described in the report on 2152 west. Those would be PGCs 1512728 and 1511341 on either side of the most northern star in the triangle.
The brightest galaxies in the entire field of view is the pair of galaxies together listed as UGC 10187 at magnitudes 15.1 and 15.5. They were obvious, and details easily held in direct vision. The halos and cores were distinct for each, with the halos nearly touching. Both were slight ovals of 1.5’ x 1.2’ with PAs of 315°. The two are slightly offset, so the PA of both together is around 290° and a combined length of 2.9’. Again, tiny visually but at 645-660 MLY, respectively, they must be huge and luminous.
As with the western half of the cluster nearly all the galaxies to the east were uniform round smudges with dimensions of no more than 0.5-1.0’ unless otherwise noted. There were interesting exceptions, however.
North-northeast of UGC 10187, and with the eastern tip of the triangle of stars pointing right at it was PGC 57081/15.8. Slightly ovalled, it had a suggestion of brightening towards the center. Around 6’ due east of UGC 10187 was the triplet of galaxies mentioned in the introduction. I only managed to see PGC 1508574/16.8. One other was much smaller and listed at magnitude 18.1. Nope. The second is listed at magnitude 16.6 so I was expecting to see it but no dice. No distance was listed, and the empty white circle designating it is usually reserved for galaxies dimmer than mag 18, so maybe it’s a surface brightness issue. PGC 1508574 showed as a 2:1 oval of 0.5’ x 0.3’ with a PA of 290° and a uniform AV smudge visible 50% of the time. Again, this is the one listed at a distance of 2.02 billion light years, and becomes my distance record, apart from quasars. It’s still considered part of Abell 2152 as a bimodal visual member, but not part of the CfA2 Great Wall as it’s far too distant to be part of that structure.
PGC 1507236/16.5 sat around 9’ due south of that distant galaxy and was nothing more than a faint, AV-only spot, visible maybe 30-40% of the time. There are several other galaxies in this general area, but they were not seen, being well into the magnitude 17 range.
Moving well to the south and near the edge of the field of view was one of the brighter pairings of galaxies which conveniently braced a visible star at equal distance to the northeast and southeast, respectively. The northern galaxy, PGC 57056/15.8 showed as a dim, round halo. The southern one, PGC 1502535/15.9, was a 2:1 oval with a brighter center. PA 45°. It’s also tied with PGC 1512728 as the most distant member of Abell 2152 seen at a distance of 681 MLY.
Due east of that pair was a shallow curve of three bright stars that served as an effective marker for 5 more galaxies. The star at the northwest end of the curve was slightly dimmer than the other two but also marked PGC 1503156/16.2 just a couple minutes to its southwest. A round, featureless AV smudge, it escaped the star’s minimal glare about 50% of the time. Maybe 6 minutes west of it was Vorontsov-Velyaminov 1792 consisting of two galaxies listed together as UGC 10193. The larger of the two at magnitude 15.4 was a thin but bright 3:1 slash with a brighter center. It was close to 2’ in length and .6’ wide with a PA of 320°. Just off its southeast tip was its 17.4 magnitude companion whose winking stellar nucleus gave it away. There are no stars near that location with which to confuse it. For all of Abell 2152, 17.4 was as dim as I was able to go, thanks to that stellar nucleus. The two galaxies are separated by 48 MLY, so the interaction was many G-years ago, or didn’t happen at all, with the pairing visual only. The star at the other end of the bright three-star curve marks two more galaxies in the area. Only 1’ east if the star and nearly lost in it was PGC 1502572/16.1, an AV smudge with a brighter core. Perhaps 8’ further east was PGC 1502749/16.7 a featureless AV smudge visible 50-60% of the time.
Two dim and widely-spaced stars extend the bright curve of three, the last star sitting 7’-8’ due north of VV 1792/UGC 10193. Another 7’-8’ further north was PGC 1504557/16.0. A featureless round smudge in averted vision only, it’s surrounded by 3 galaxies of magnitudes above 17 that were not seen.
Continuing north maybe 20’ brought me to two bright, widely spaced stars angled northeast. Placed exactly between them was PGC 1506294/16.6 which was AV only, featureless and round, but actually held in direct vision once or twice. In the position of an imaginary third star in the line, and at the same separation as the two real ones, was PGC 1508044/16.7. Seeing it was dependent on knowing it was there, which is where the detailed finder charts came into play. Continuing to look askance at that location resulted in the dimmest of smudges puffing into view maybe 20-30% of the time. It moved with the starfield when the tube was bumped.
At the very eastern edge of the field of view was HD 144724, blazing away at magnitude 7.8. Roughly halfway between it and the pair of bright stars just mentioned sits a group of four galaxies of which I saw two – PGC 1505993/16.2 and PGC 1505784/16.5. Both were featureless, round, and AV only.
UGC 10204 just to the southwest of HD 144724 should have been a snap to find at magnitude 14.0, but it wasn’t. Even taking the 7.8 mag star out of view didn’t remove enough glare to make the galaxy a direct vision object. Instead it was a disappointing 1.5:1 dim but large uniform smudge 1.5’x1’ with a PA of 80°. It’s listed in Pretty Deep Maps as an SO-a with an SB of 21.4, which seems rather bright for what I was able to make out.
Only 3 more galaxies were seen in this field of view, widely scattered in the northern portion of it. Remember the bright pair of stars and PGC 1508044 standing in for a third? If so, continue in the same direction as far from the galaxy as it is from the previous star and you’ll come upon a third star in the line after all, at twice the distance that separates the first two. 6 minutes or so to the southeast of it I was able to locate PGC 571399/15.3. It was bright enough to be held in direct vision, though the extent of its 1.2’ round halo and brightness of its core were best seen In AV. Right at the northeastern edge of the field of view is a bright star that constitutes a fourth star in the line mentioned. To its southwest, and about a third the way back to star #3, PGC 57138/15.6 appeared. A featureless round halo, it was nonetheless held in direct vision about 50% of the time and always in AV. Taking star #4 and the bright galaxy as two points of a scalene triangle, further west and due west of the star, PGC 1512051/16.1 makes the third point. A consistently visible star just to its west marks the position of this featureless and AV-only smudge.
This was the second field of view completed during this all-night session, and it was beginning to tell on me. My friend Scott at the club will tell you that the concentration needed for this kind of observing is exhausting. He’s not wrong. So many barely-there to threshold objects that come and go in a field in which they’re not even visible at medium power just taxes the brain. By this point it was somewhere around 2 AM, so I took a short breather in the observatory break room. An energy bar, a cuppa and it was off to field #3, between 2152 and 2147.
The CfA2, Great Wall of Galaxies** been quite **a journey, and one I’m glad to have undertaken. It’s not only enlarged my perspective on the universe but also forced me to develop my observing abilities. I’m coming to realize, however, that it’s a journey that will never truly end. There will always be more members to find in the 7 AOCs and their surroundings, not to mention picking up galaxies here and there in the vast reaches between them and the more sparsely populated western half should I decide to take on that challenge. But I think I can say now with some confidence that I’ve seen CfA2, the Great Wall of Galaxies (galaxy count as of 9/13/2025 = 210). The rest will be icing. But I really do like icing…
Truth be told, far-and-away most of the galaxies are beyond the possibility of visual detection. That said, it still astounds me that I’ve recorded somewhere between 7%-12% of the major galaxies associated with this vast structure, depending on which population number is used – 1732 or 3000+. Actually seeing a representative portion of the Great Wall and being connected to it by those long-traveled photons pinging my retina is something I can’t put into words. Does it make me feel small? Yes, it does. Infinitesimal in fact. But insignificant? No. I can contemplate those galaxies. They can’t contemplate me. But they do compel me to question my essential presuppositions, asking questions like, “Why is there something rather than nothing?”
Once again, I must thank Gayle Rigsbee and the Charlotte Amateur Astronomers Club for enabling me to realize the dream that Voyage to the Great Attractor planted in my heart and soul all those years ago. It’s a dream that has not left me unchanged.
Butch Phaneuf