Among all of the telescopes, eyepieces, star charts, chairs, portable power tanks, dew-prevention heaters, and other paraphernalia associated with an observing session, one item stands apart and is often taken for granted: a useful vehicle that can carry all of one’s stuff (and junk) to and from an observing site, often over rugged terrain and rough, unmaintained roads. No astronomy gear gets as much use outside of the hobby; nothing is as important to the overall American way of life as the independence brought by having reliable transportation.
And so it was that the news that the Caveman-Mobile was going to be totaled out after a minor fender-bender came as a huge disappointment. It wasn’t just that I could haul multiple scopes and other folderol to places that once would’ve been labelled “Here be tygers”; it was that I’ve come to be used to having the ability to travel at a moment’s notice. (Did you think we hunted mammoths on foot?)
The Moon-dark phase of July coincided with this unfortunate development. Mrs. Caveman and I had put more than a thousand miles on the CM during our geology trip around the state’s interior during the first week of the month; the CM went into the shop and was declared a loss on July 9th. Until that point, however, I put the poor vehicle through our usual round of dark-sky offroading.
I. When last I wrote, I noted that the summer provided me with a choice: continue working on spring Herschel galaxies despite their being in a highly-diminished state (due to being so far past the meridian); work on Herschel objects in the Milky Way (open and globular clusters, planetary and emission nebulae); or skip working on the Herschels for a while and trot out the 18″ EAS scope to explore more off-the-beaten-path objects. I spent the Moon-dark phase doing the latter two, and this first night of what would be a very long run was spent with the 18″ and a list I’d compiled from various Astronomical League lists, the Deep Sky Forum Object of the Week threads, and Alvin Huey’s wonderful observing guides (available here).
And yet I spent the night extremely frustrated. The 18″ is a fine scope, but it’s far less user-friendly than Bob the Dob, and it suffers from a poor mirror coating which leaves the mirror reflecting considerably less light than it should. While it’s nice to have the extra aperture and (supposedly) extra light grasp, I often found myself disappointed with the experience of using the scope. (In fairness, much of this wasn’t the scope’s fault but was mine.) It didn’t help that conditions were much softer than expected, or that there was considerable dew present.
MOON: 24 days (36% illumination); rose at 1:40 AM
NELM: not checked
WEATHER CONDITIONS: temps falling to mid 50s; air still, considerable dew
Others present: RA, JA (John, RA’s father), SF, JO
Nonetheless, I stuck it out. From my list, I observed the NGC 5419 group, Hickson 72, the loose, faint globular cluster NGC 5466, and the super-thin flat galaxy UGC 9000; all of these targets were located in the rapidly-setting constellation of Boötes the Herdsman. Disappointed as I was, I took no notes during the session—of these targets, only NGC 5466 afforded a good-enough view to warrant committing to audio, and I had already recorded it in the 12.5″ way back at the Giant City State Park wildlife reclamation meadow in 2014. (That’s certainly no reason not to take notes again, of course.)
So I spent time wandering among many of the showpiece objects of the sky, sharing the views with the other observers (Jerry, Steve F [from my OSP tribe], Robert A and his father John) and reminding myself that the ten days ahead looked to be quite promising for observing. We went through the usual suspects: M80, M4, M9, M10, M12, M14, M51, M101, M13, M5, M15, The Veil/Lagoon/Trifid nebulae, the fine double star Alpha Herculis (which refused to focus sharply, despite collimation being pretty-well on target), and three visible planets—Jupiter, Saturn, and Mars. (Mars looked surprisingly fine, given the scope’s optics, the planet’s low declination, and the dust storm engulfing the planet’s surface). And with the Moon about to rise, I remembered to swing over and pick up Comet Giacobini-Zinner, which presented a fine apparition.
It was an inauspicious beginning to what would prove an exceptional week-plus stretch of observing.
II. We reconvened the next night at Eagle’s Ridge, as the transparency and seeing forecasts were better than at Eureka. As it was a decent-sized group of observers, we parked and observed from the road junction rather than our usual spot on the spur road. I chose to bring Bob the Dob this time, and my observing list included some actual Herschel objects (labeled below with an [H]) mixed with a number of non-Herschel targets, including several globular clusters I hadn’t yet observed (I’ve gotten almost all of those visible in a 12.5″ scope from mid-northern latitudes, and would gather several others during the course of this run.)
I took fewer notes during this run—certainly fewer than my epic swing through the Virgo Cluster the year before—and spent more time looking at the showpieces in between hunts for those objects I hadn’t seen. I felt less duty-bound to stick to my Herschel plan than usual, although I also spent several nights putting off wading into the ranks of the Herschel open clusters that spattered the arms of the galaxy with young stars. For many reasons, the open clusters held less appeal than the remainder of the objects. (How wrong I would of course be.)
MOON: 25 days (26% illumination); rose at 2:10 AM
NELM: not checked
WEATHER CONDITIONS: temps falling to mid 50s; air still, minimal dew
Others present: JO, Bill M, Bob M, FS, AG
(H) NGC 6058 (Her): It’s still a bit twilighty or not totally dark, but I’m going to proceed anyway. This is a small round planetary nebula that presents an almost galaxy-like aspect; it’s about 0.3′ in diameter, with a small outer halo and a “core” region that encompasses the inner 2/3 of its diameter. This inner region is quite bright and makes it difficult to ascertain if there’s a central star visible. I suspect that the central star is visible and quite bright amid the brightness of the nebula’s interior. [For whatever reason, I appear to have not tried a UHC or O-III filter on the nebula.] The nebula lies in the middle of a ‘Y’ asterism whose stem stretches S and whose branches lead NF and NP the nebula; 5′ to the NP is a 9.5-magnitude star, 6′ to the NF is a 9th-magnitude star, and 3.5′ S of the nebula is an 11th-magnitude star. Other stars in the field include a 13th-magnitude star 2.5′ F very slightly S of the nebula, another 13th-magnitude star S very slightly F the nebula by 4′, an 11.5-magnitude star S very slightly P that previous star by 3′, and a 9.5-magnitude star 3.5′ S very slightly P the 11.5-magnitude star by 3.5′.
I also spent some time ferreting out Abell 39, the large, perfectly-round planetary in Hercules that I first observed at the Brothers Star Party a year before. I’d taken notes on it then (“Band of Brothers”), so I didn’t do it again this time; I should take notes on every object I observe regardless of whether or not I’ve seen them before, but I haven’t yet developed that discipline.
I also had Mrs. Caveman pick me up some black fabric to use as an observing hood, having used one at Jerry’s house to do some solar observing. It’s long been recommended to use the hood when observing extremely faint objects; it cuts out stray light and reflection from the ground enough to provide extra contrast in the eyepiece. For a number of objects during this run, it may have made the difference between seeing them and missing them entirely.
IC 1257 (Oph): This is one of the toughest globular clusters I’ve observed (and there would certainly be a few more before this dark run ended); it’s as or more difficult than some of the Palomars. This one is no more than 13th magnitude, and barely visible with direct vision even though I’m using an observing hood here. The cluster is no more than 0.75′ in diameter and nothing more than a small fuzzy glow; no resolution is possible and it’s too difficult to get an estimate of its concentration class. Yet it’s most definitely in the eyepiece! The cluster is 14′ N of an 8.5-magnitude star, and about halfway between (and a tiny bit N) of two 11.5-magnitude stars, one P and one F the cluster. It’s slightly closer to the star to the F side; it’s 6.5′ from the star to the P side and 6′ from the star to the F. The 11.5-magnitude star to the P side is at the center of a very tiny ‘y’ (lowercase) pattern; NF that star by 2.25′ is a 14th-magnitude star; there’s a 15th-magnitude star S slightly P the 11.5-magnitude star by 1′, and a 14th-mg star F the 11.5-magnitude star by 1.75′. S of the globular by 4′, and SF by 4.75′, are two 14th-magnitude stars; there are also 14th-magnitude stars NF and F slightly N of the cluster. The 8.5-magnitude star S of the cluster has an 11.5-magnitude star NP it by 3′ and an 11.5-magnitude star SF it by 6′.
Haute Provence 1 (Oph): not nearly as tough as IC 1257, but not at all easy; I can’t believe this one has been rated for 8-inch scopes in the iDSA. This globular shows as a weak, misty patch of light in both the 14mm ES and the 10mm Delos, even under the hood. It’s very slightly over 1.0′ in diameter, but too faint to try to get a Shapley-Sawyer class—I suspect this one to be on the low end of the scale, given its very even illumination. A 6′ long arc of three stars to the N of the cluster extends NP-SF; the brightest of these is 9.5-magnitude and is on the SF end of the arc, while the other two in the arc are of 11th-magnitude. A much smaller arc of three bends around the N end of the cluster; these are all 12th-magnitude. There’s also a line of three stars S of the cluster by 7′. F the cluster by 7′ is a 10th-magnitude star. An 8.5-magnitude star lies 17′ S slightly P the cluster, and a 9th-magnitude star is 3′ S of the 8.5-magnitude star.
Abell 43 (Oph): Staying under the observing hood here, given that it’s helped quite a bit with the past couple of objects. This planetary isn’t super easy, but I did manage to spot it without a filter when I swept the area. It’s only about 1.25′ diameter—not “huge” like Abell 39 was earlier. My O-III filter darkens the field and throws it out of focus so much as to be barely usable, but with the filter in the 14mm ES, I can hold the nebula steadily in direct vision. The filter makes the central star nearly invisible, although the star is roughly 11th-magnitude. Switching to 10mm Delos+filter, hints of annularity can be seen amid the roughly-circular halo. On the F edge of the nebula there appears to be a very very faint, threshold-level star that’s impossible to hold steadily (this was found without the filter and disappeared with the filter in; SkySafari lists the star as magnitude 13.3, but it seems much fainter than that). The nebula is between a 9th-magnitude star 3.75′ to the NP and an 11.5-magnitude star 3′ to the SF; there’s another 11.5-magnitude star SF that second star by 1.5′. These three stars form a triangle with a third vertex 11′ SP the 9th-magnitude star (the two stars to the SF of the nebula serve as one vertex). The edges of this triangle run NP the nebula to SP, NP to SF, and SP-SF the nebula; the nebula is along the NP-SF edge. N of the nebula by 2.5′ is a 12th-magnitude star. On the F edge of the field, 18′ from the nebula, is a pair/double of 10th-magnitude stars separated by 0.3′. N of the nebula by 20′ is the brightest star (8th-magnitude) in the field, which has a 10th-magnitude star 1.75′ S of it.
(H) NGC 6629 (Sgr): Quite a bit smaller than the other planetaries I’ve observed this evening; the O-III filter makes little difference other than to increase the contrast and annihilate the rest of the field. This nebula is only about 15″ across, with a brighter 9″ inner region. The central star is extremely faint with the filter and not much brighter without it; I have a very hard time holding it steady. S slightly F the nebula by 2′ is a 10th-magnitude star; due N of the nebula by 7′ is an 8th-magnitude star. There’s another 8th-magnitude star 20′ SF the nebula. 14′ SF the nebula is a 9th-magnitude star. 2.25′ N slightly P the nebula is an 11.5-magnitude star; there’s a 12.5-magnitude star 2′ NP the nebula that might be a close double.
III. The next night, we were out on the spur road, which branches northeast from the Eagle’s Ridge road junction. The Moon had yet to hit New, but we were already on our third night of observing for the cycle. I’d bought a couple of cans of fluorescent chartreuse spray paint with which to mark the potholes on Eagle’s Rest Road; some of these would be axle-breakers if they an unsuspecting driver hit them on the road, and I had made up my mind that none of us would be the victim. However, despite the promise of day-glo yellow, the paint showed up on the black road surface as a medium (and uselessly-dark) green. Best-laid plans and all that. I ended up using up one can of the paint (and a week’s supply of curse words) and taking the other back to Lowe’s, where I picked up a couple of cans of white spray paint designed for road surfaces and athletic fields; I have yet to have the opportunity to use them.
I’d left early to make sure I got the pothole-painting done with time to get to the top of the Ridge, and I ended up being the first one up by about fifteen minutes. There was a slight haze of forest-fire smoke visible low in the sky; we’d been lucky fire-wise so far this summer, and this was still only a minor issue compared to past years. Still, the SQM reading on the night was somewhat less impressive than usual for the spur.
There was also the matter of a traditional summer problem, one we hadn’t often had issue with observing here in Oregon: mosquitoes. This might have been the first time I felt compelled to go for the DEET at Eagle’s Ridge, but it didn’t take long to do so. The worst aspect of DEET is that it’s so destructive to plastic and optical coatings; it’s necessary to make sure one’s hands are free of the stuff when picking up gear, and even more necessary to avoid bumping DEET-covered skin into eyepiece lenses. I’ve read numerous reports about picaridin-based repellents and their being free of DEET’s many disadvantages, and I plan to invest in the stuff before our next outing. (The mosquitoes would be even worse at Champion Saddle a few nights later.)
A bigger problem reared its head as I was setting up. My Powertank, a 12-volt battery replete with charging and power outputs of various sorts, refused to turn on when I set up my dew-prevention rig. No amount of finagling would get it going. Without it, I’d be at the mercy of eyepiece-fogging and the threat of my secondary dewing over. Fortunately, Jerry happened to have a spare 12-volt that he was willing to let me use for the session. Even more fortunately, he’d worked on Powertanks before and knew how to fix them (if it was indeed fixable). He suggested checking it to make sure it had actually charged (and that the charger wasn’t dead), and then he would take it apart to see what the issue was.
We had with us both John (Robert’s dad), who was at Eureka Ridge the first night of the run, and Janet W, on her first observing session with us. Janet drove an electric Fiat 500 with a 90-mile range, but was worried about the last half-mile up to the Ridge and its effect on her battery (understandably so). So she parked at the beginning of the gravel stretch and got a ride from Jerry the rest of the way up the mountain.
One of my primary targets this night—missed the night before—was the globular cluster pair NGC 6558 and NGC 6569. I’d observed them numerous times before, often in the same eyepiece field, but I had somehow never taken notes on them. This was a mystery to me, because I (mistakenly) believed they were both Herschel objects. (As it turned out, only 6569 was a Herschel; in any case, they were globulars within range of my scope that I’d never done notes for.) I would again fail to get these two; they’re in the middle of Sagittarius’ “teapot spout,” and this part of the constellation only spends a short amount of time above the mountain ridge to the south of Eagle’s Ridge. By the time they cleared both the ridge and the couple of trees that just happened to be in my way this particular night, I was too preoccupied to swing back to pick them up.
My first target of the night was another that I was sure was a Herschel and turned out not to be. This too would be a continuing theme during the run.
EAGLE’S RIDGE SPUR ROAD (43° 48′ 17.9496” N, 122° 42′ 45.6912” W)
MOON: 26 days (16% illumination); rose at 2:45 AM
NELM: not checked
WEATHER CONDITIONS: some smoke from forest fires; occasional hazy clouds low in E/SE; temps falling to mid 40s; air still, considerable dew (secondary dewed over completely)
Others present: JO, RA, JA (John, RA’s father), JW (Janet)
NGC 6210 (Her): I’ve observed this PN several times over the years, starting with my C-8 from my Cincinnati backyard, but only on that occasion did I take notes on it—I’m mystified why I haven’t seriously gotten to it before. It’s a decent-sized, very bright planetary, with a 20″ inner region and a few arcsec of “fringe” around it (for a total of about 26″). Without a filter, the nebula has a very pale bluish cast to it. The brightness of the inner region makes it difficult to pick out the central star, and I can’t say with certainty that I’m seeing it. 9′ SF the nebula is one of three 7th-magnitude stars in the vicinity; the other two are S very slightly P the nebula by 18′ and P slightly S of the nebula by 23′ (so just outside the P edge of the field with the nebula centered). NF to F very slightly N of the nebula is a small triangle consisting of a 9.5-magnitude star and two 12th-magnitude stars; the S-most 12th-magnitude star is the closest of the three to the nebula, at 2.5′ distance NF the nebula, while the 9.5-magnitude star is 4.75′ F somewhat N and the other 12th-magnitude star is about 6′ NF. The longest side of the triangle (with both 12th-magnitude stars) faces NP.
NGC 6240 (Oph): This odd little galaxy is also known as VV 617; it’s actually a merger of two galaxies, appearing as one object. A super-bright infrared source, this galaxy was featured on the Astronomy Picture of the Day site in June 2009 (https://apod.nasa.gov/apod/ap090618.html) and was the Object of the Week on the Deep Sky Forum for May 11, 2014. I first observed it and took notes on it in late June 2016. It’s a difficult but fairly obvious streak not really well-served by this aperture and magnification, but still well within the grasp of the 12.5″ scope. The galaxy is 1.0′ x 0.67′ (at its widest, e.g. the S end) and oriented S very slightly P-N very slightly F. Greg Crinklaw nicknamed this galaxy “The Rumpled Starfish,” but it doesn’t really give any but a vaguely-triangular shape. The halo is moderately-well defined, and there’s a slight bit of central brightening along its length. There’s no visible nucleus (not surprising, given the disruption occurring within the galaxy). Faint stars imeediately surround the galaxy: there’s a 14th-magnitude star to the N and a 14.5-magnitude star to the south, each 1.75′ from the galaxy; a 14th-magnitude star is also just outside the halo to the F side. 7′ due S of the galaxy is a 9.5-magnitude star, while a 10.5-magnitude star lies 10′ F the galaxy. SP that 10.5-magnitude star is a pair of stars, 11.5- and 12th-magnitude; the brighter of the two is S of the fainter by 1′. P and somewhat S of the galaxy by 6.5′ is the brightest (11.5-magnitude) vertex of a very small triangle; this is the closest of the vertices to the galaxy, with the other two (both 14th-magnitude) P and SP the 11.5-magnitude star.
Abell 55 (Aql): This quite-difficult planetary is completely invisible without a filter, and very faint even with my old Lumicon O-III. Jerry’s NPB filter does a much better job, revealing a 45″ x 30″ glow, elongated P-F. No central star is visible, and the nebula appears to have no real annularity to it, just a largely-even glow; the P side of the nebula seems slightly brighter than the F side [this is perhaps due to the two stars embedded in the P side of the nebula, which were not otherwise seen ]. A 10th-magnitude star lies 6′ S of the nebula. 9′ N v slightly F the nebula is a 10.5-magnitude star that has a 12th-magnitude star F slightly S of it by 3.25′. On the SF edge of the field is an 8th-magnitude star. Outide the field, 25′ P very slightly N of the nebula, is a 6th-magnitude star.
It was about this point that Jerry tracked down the asteroid 4/Vesta, which had just given a terrific apparition during its June opposition. Still slightly visible to the naked eye, the asteroid lurked near the globular cluster M9 in Ophiuchus, and presented an impressively-bright image in Jerry’s trackball scope. Not having seen many asteroids (of which I was aware, anyway), I made sure to get a good look at this one. Then it was back to the deep sky:
Palomar 10 (Sge): After years of talking about hunting this globular, and a few half-hearted attempts, my first serious attempt at Palomar 10 is a success. (I have to admit I was a bit surprised to see it; Jerry confirmed that it was there, however.) The cluster is difficult but definite, just on the line between direct vision and needing averted to catch it. Averted vision does considerably improve the view. It’s a very diffuse, misty 2′ glow, much too faint to derive any value for concentration class and otherwise devoid of any real detail in a crowded Milky Way field. On the cluster’s F edge is a 13.5-magnitude star. S of the cluster and running roughly P-F is a long train of stars: SF the cluster by 8.5′ is a 10.5-magnitude star; an 11th-magnitude star is 7.5′ S very slightly F the cluster; this 11th-mag star has a 13th-magnitude star SP it by 0.5′. Also in this train is a very small isosceles triangle, SP the cluster by 12′; the N-most vertex of the triangle is 10th-magnitude; P very slightly S of this 10th-magnitude is another of the same brightness, and from this second star 0.75′ S very slightly F is a 13th-magnitude star. Still in this train: SP the cluster by 5′ is the brightest (at 12th-magnitude) and S-most vertex of another long, thin triangle; the other two stars are 13.5-magnitude. The brightest star in the field is an 8th-magnitude star 17′ N of the cluster. There’s also a 9th-magnitude star 18′ N somewhat F the cluster.
I don’t recall why I stepped away from my scope; it might have been to check a chart, to put something on my observing table, or simply to stretch. In any event, I looked over toward the Scorpius/Ophiuchus/Sagittarius boundary region just in time to catch a spectacular meteor fireball streaking through that part of the sky, perfectly parallel with the mountain ridge to the south. Even though it lasted for several seconds, I didn’t have the brainpower to process what it was and shout an alert to my fellow observers before it disappeared. Having seen the great Leonid storm of 1998, I can still rank this as one of the best meteors I’ve ever seen.
(H) NGC 6818 (Sgr): From a difficult object to a really easy one. The Little Gem Nebula was also a DSF Object of the Week (just this July 1st), and is another object I’d seen numerous times (usually in conjunction with observing Barnard’s Galaxy, NGC 6822, just to the S). Having returned Jerry’s NPB filter and still grumbling about my O-III, I’ve decided to use my UHC on this nebula instead. It doesn’t need much of a filter; it’s very bright and obvious, with a distinctive pale blue color. The nebula is 0.3′ and roundish; other, better observers have noted it to be slightly elongated, although the DSF thread notes that this might be more obvious in an O-III (which I’m not using). With the UHC, there’s not much change from the unfiltered view aside form an increase in contrast; there’s perhaps a bit of outer halo better visible in the filter than without, maybe a bit of irregularity in the overall surface brightness, and the F side might be a tiny bit brighter than the rest of the nebula with the filter. No annularity is visible in either view. The nebula is bounded to the NP, F, and SP sides by faint stars: 0.3′ NP is a 13.5-magnitude stars, and the other two stars are of 14th magnitude. SF the nebula is the brightest (9.5 magnitude) of a faint diamond of stars whose major axis is 2.5′ and whose minor axis is 1.75′; this 9.5-magnitude star is 9′ SF the nebula, and is the farthest of the four stars from the nebula. P the nebula by 15′ is the brightest star in the field, a 7.5-magnitude beacon. S of the nebula by 22′ is a 9th-magnitude star; also S of the nebula, by 16′, is a faint line of stars stretching roughly P-F; the star at the F end is the brightest of this group at 13th-magnitude; the other two are 13.5-magnitude, and all are spaced about 0.5′ apart.
Abell 65 (Sgr): Another DSF Object of the Week, this one from June 3rd. This one is quite low in the sky and pretty difficult; it’s not visible without the UHC filter. It’s a diffuse, almost featureless 3.0′ x 1.5′ glow, elongated NP-SF, with no central star visible. At each end of the major axis is a 13th-magnitude star. Two asterisms dominate the field: a miniature Big Dipper P the nebula and a capital ‘Y’ pattern F the nebula. The mini-Dipper consists of five stars (mostly 10th-magnitude), with the bowl of the Dipper closest to the nebula and pointing S; the Dipper’s handle arcs away N slightly P. A long trail of much fainter stars runs N-ward from the end of the Dipper’s handle, and this extends the length of the Dipper out to about 20′. P the star at the end of the handle by 6′ is a 9th-magnitude star. The ‘Y’ asterism is also made mostly of 10th/10.5-magnitude stars, although the star in the middle of the ‘Y’ is 11.5 magnitude. The ‘Y’ runs roughly parallel to the Dipper, with the stem pointing NP and the two forks facing S and SF. The brightest star in the field lies 17′ S slightly F the nebula, and is 9th magnitude; there’s an 8.5-magnitude star just outside the NF edge of the field (23′ from the nebula).
(H) NGC 6804 (Aql): This is quite an impressive planetary nebula, especially after several really faint objects. It actually looks a bit like a small spiral galaxy, in terms of brightness profile. It’s 1.0′ x 0.75′, elongated SP-NF, with well-defined edges. With the UHC filter, there looks to be a slightly-brighter inner rim inside the edge of the nebula’s smooth disk. There are several stars across the nebula’s face—at least three—and one of them is likely the central star, but it’s hard to tell and none looks perfectly centered. [A bright satellite cuts through the field here.] The brightest star amid the nebula is a 13-magnitude star on the NF edge of the disk. The nebula sits at the intersection of a ‘T’-shaped pattern (or the P-most edge of a triangle, if you prefer); 6′ SF is an 8.5-magnitude star, and this has another 8.5-mag star due N by 5′; this second star has a 10th-magnitude star to the NP side. 5′ NP the nebula is a 9th-magnitude star, while there’s a 9.5-magnitude star SP the nebula by 13′. The brightest star in the field is 7th magnitude and sits 11′ NF the nebula.
The mountainside gave us a short reprieve from the Moonrise, during which I caught my last two objects. Even with moonglow taking over the eastern sky, I’d managed an Abell planetary down low in the sky. Eventually, though, the Moon cleared the mountainside and the Milky Way began to lose its sharpness. With clear skies scheduled for the rest of the week, there was no regret in leaving after six hours, no worry that objects missed would have to wait until next year.
IV. The fourth night of the run found the Caveman-Mobile in the shop, and we’d already been given the bad news. Mrs. Caveman was rather despondent, as she had been looking forward to having the van paid off and being free of a car payment after November. It would all work to our benefit, of course, but at this point we didn’t yet know that; as it turned out, we were able to buy the van back with the understanding that it was considered salvage. This would give us an opportunity to get a new, smaller and more fuel-efficient vehicle for town driving while retaining the Caveman-Mobile for telescope hauling.
Without available wheels for the 9th, however, I hitched a ride with Dan B up to Eureka Ridge. Although Dan had plenty of room for another telescope in his truck, I took only my trusty old 11 x 80 Celestron binoculars, which I hadn’t used in years. The opportunity to work up and down the Milky Way with binos was one I’d been neglecting for a while; I’d planned to use them at Brothers in 2017, and got hooked instead on using the scopes I took with me. (I had used them at the Oregon Star Party in 2016, but only as a warm-up to a night with the 18″ scope.) Tonight, Dan had his 11″ SCT and Jerry (with Kathy and Dan R on board) would be bringing the 20″ TriDob, so I felt comfortable not bringing along a scope—a telescope also necessitates bringing along an eyepiece case, charts, a chair, a table, etc. etc. etc. Going light once in a while was a very good thing.
Tonight, it was a Very Good Thing. Although the Milky Way seemed to be “softer” and less-glittery than at Eagle’s Ridge (or even on other occasions at Eureka), the Milky Way’s dark dust clouds seemed to be a tangible entity of their own, one with more detail than I’d ever seen, even on superior nights. The Great Galactic Dark Horse in southern Ophiuchus wasn’t just something in pictures; it was actually something there in the sky in its entirety. Barnard’s ‘E’ in Aquila could be easily picked out as a small black spot near Tarazed (Gamma Aquilae), and Le Gentil 3 (near Deneb) was an inky, starless blot amid the dazzling Cygnus star-clouds. The Great Rift itself, stretching from Cygnus down into Ophiuchus, looked like the galaxy had been ripped asunder to reveal the blackest of voids beyond. Even the veins of darkness that led toward Antares from Ophiuchus, so striking in photographs, were faintly traceable on the sky and obvious in the binoculars. With the binoculars, too, dozens (if not more than a hundred) of other, smaller dark nebulae burst into view like hatching Cthulhu-spawn: The Snake Nebula, the Coalminer’s Lungs (in the Small Sagittarius Starcloud), those dark squiggles that wrap around the Scutum Starcloud… I lost track of them all, but swept back and forth throughout the Milky Way, oblivious to what the other observers were looking at. (I did eventually use the TriDob to explore the NGC 6723/Corona Australis region of light and dark nebulae, and for a peek at Minkowski’s Butterfly, a target on my own list.) It was as fulfilling a night as any with a full-fledged telescope, and one much-needed after spending the year tracking down smaller quarry.
MOON: 27 days (8% illumination); rose at 1:40 AM
NELM: not checked
WEATHER CONDITIONS: temps falling to mid 50s; air still, considerable dew
Others present: JO, KO, Dan B, Dan R
V. I had to have a break from observing at some point during the run, and others evidently felt the same way; we all stayed home the night of the 10th/11th. When we reconvened, it was at the Eagle’s Ridge spur road. I had both the Caveman-Mobile and considerable energy back, and Jerry would also have my Powertank back (having fixed the broken switch that had caused all of the problems).
I opened the night with Minkowski’s Butterfly, which we’d looked at during the last Eureka trip, but I also had an alarm set for the NGC 6558/6569 pair, to catch them at transit. I wasn’t going to miss them again. Many of my other targets ended up being open clusters, a class of object of which I’d only scratched the surface.
EAGLE’S RIDGE SPUR ROAD (43° 48′ 17.9496” N, 122° 42′ 45.6912” W)
NELM: not checked
WEATHER CONDITIONS: temps falling to mid 40s; air still, moderate dew
Others present: JO
Minkowski 2-9 (Oph): This is Minkowski’s Butterfly, a tiny but obviously bilobed planetary; in the 14mm ES, it’s a very thin streak with a brighter middle (but no visible central star). The nebula is elongated N-S and is no larger than 0.3′ x 0.125′. Even using the 6mm Radian (262x, 0.2˚ TFOV) and the UHC doesn’t do much more than make the middle of the nebula (where the central star would be) seem a little bit wider and enhance the overall contrast. As with Palomar 10, I’m actually a little bit surprised the nebula is this… easy in the 12.5″ scope; we’d observed it the night before in the 20″ TriDob and it didn’t look that much more impressive than it does here. To the S slightly P the nebula is a 10.5-magnitude star that’s the N-most vertex of a small, thin parallelogram: S very slightly F that vertex by 0.67′ is a 13.5-magnitude star; SP the first star by 1.75′ is a 12th-magnitude star; S very slightly P this last star by 0.25′ is a 14th-magnitude star. NP the nebula by 8′ is an 11th-magnitude star. N of the nebula by 3.5′ is a 13.5-magnitude star, and there’s another 13.5-magnitude star SP the nebula by 2′. 2.75′ NP the nebula is a 15th-magnitude star, and N very very slightly P the nebula by 15′ is a 10th-magnitude star. The brightest star in the field is 10th magnitude and is P the nebula by 15′.
(-, H) NGCs 6558, 6569 (Sgr): These two globulars have somehow eluded my taking notes on them (and thus counting them as “seen,” despite my having observed them multiple times before) since I began the two AL Herschel lists four years ago. NGC 6558 is pretty unconcentrated, its central region not that much brighter than its halo; the overall brightness contour of the cluster is pretty smooth, and it doesn’t quite reach granularity. The cluster is about 1.5′, although it might be slightly elongated N-S (or there may be some cluster stars on the verge of resolution on those ends that make the cluster appear elongated). There are certainly several faint field stars (or cluster members) to the S, just on or slightly beyond the edge of the halo. The cluster itself is inside a small trapezoid of 13th-magnitude stars: one due P, one NF, one N, and one S slightly P the cluster. Due N of the cluster by 14′ is an 8th-magnitude star; with that star on the edge of the field, another 8th-magnitude star can be seen 23′ due S of the cluster (this star is beyond the edge of the field when the cluster is centered). 4′ NP the cluster is a pair of 11th-magnitude stars separated by 1′ and oriented NF-SP each other. NGC 6569 is just outside the edge of the 42˚ field with 6558 on the opposite (F) edge (so about 43′ from 6558). It’s considerably brighter, slightly larger, but only slightly more concentrated than 6558. As with its neighbor to the P side, it’s stubbornly unresolved, although it seems closer to being resolved than does 6558. The halo seems more “ragged” on the NF and slightly more extended toward the SF. One cluster star (could be a field star) lies F slightly S of center on the periphery. S and SF the cluster is a small triangle of brighter stars, including the brightest in the field (7.5 magnitude, S of the cluster by 8.5′); N slightly F that star by 4′ is a 10.5-magnitude star, and 5.25′ F very slightly N of the 7.5-magnitude star is an 11th-magnitude star. SF the cluster by 2.5′ is a 12th-magnitude star. SP the cluster by 1.5′ is a 12th-magnitude star, and further SP is an 8.5-magnitude star 17′ from the cluster.
(H) NGC 6568 (Sgr): This open cluster requires sitting on the ground to observe. It’s a pretty large cluster of about 60 stars, fairly detached from the Milky Way; there’s not much doubt that it’s a cohesive entity. The majority of the stars are in the 11th/12th-magnitude range, with some stars fainter but almost none brighter than that. The whole spans about 12′ x 8′, but the dominant feature of the cluster is an 8′ x 4′ ‘S’-shaped pattern at the N end of the cluster and oriented P-F. This ‘S’ is unmistakable once seen. The majority of the cluster’s faintest stars seem gathered along the middle of the ‘S’. There’s also a N-S running line of 12th/14th-magnitude stars on the P side of the cluster; this line is about 15′ long, and is separated from the cluster by an 18′ x 5′ strip of dark nebulosity that runs parallel to the line of stars. With the ‘S’ centered in the field, the brightest star in the field (6th-magnitude 14 Sgr) lies 21′ to the F slightly S edge of the field; this star is slightly yellowish and has a 12th-magnitude star P very very slightly N by 1.25′. N slightly F the ‘S’ by 20′ is an 8.5-magnitude star [at the moment, there’s also a very slowly moving satellite crossing the cluster from P to F]. Between the ‘S’ and 14 Sgr, 8.5′ from the center of the ‘S’ is a small knot of stars just on the edge of visibility with an unresolved appearance; this knot is 0.67′ in diameter and has several faint stars resolved in it.
(H) NGC 6604 (SerCau): Asterism? Cluster? It looks like the former, although it’s been proven to be the latter. This cluster is a grouping of 5 or 6 main stars no more than about 2.75′ across. The Milky Way is quite thick in this area, and the cluster isn’t that well detached from it. Also detracting from the cluster’s identity is the fact that the member stars are of quite mixed magnitudes: the brightest of the cluster’s stars is 8th magnitude; this star is flanked to the N very slightly F (by 0.67′) and the P very slightly N (by 1′) by two 9.5-magnitude stars; the star to the P very slightly N of the lucida has an 11th-magnitude star to the NP, and this 11th-magnitude star itself has a 12th-magnitude star to the NP by 0.25′. These five make up the main body of the cluster, although there is some unresolved starglow among the five that might be part of the cluster or could be general Milky Way glow. The cluster is bounded by two 8.5-magnitude stars: one to the NF by 12′ and one to the S v slightly P by 17′. 5′ S of the cluster and stretching 5′ to the SP is an arc of dark nebulosity that is quite opaque but best observed in averted vision. NP the cluster by 12′ is an interesting double star; the 9.5-magnitude primary is 9″ NP the 12th-magnitude secondary.
(H) NGC 6633 (Oph): Certainly one of the brighter open clusters I’m liable to run across doing the Herschel lists. This one counts perhaps a hundred stars in a 35′ circle; most of these are 7th/8th magnitude, although a number of scattered fainter stars in the field may also belong to the cluster. The main body of the cluster forms an Eiffel Tower-shape that stretches from the SP to the NF of the field. This Eiffel pattern has an “arm” of ten stars that arcs off from near the middle of the F side to the NF and then to the SF of the main pattern. A third portion of the cluster lies P very slightly S of the Eiffel pattern, containing 13 stars of which the brightest is 8th magnitude and lies in the NF of that separate clump; a line of five fainter stars trails from this clump toward the SP, giving this part of the cluster the appearance of a lacrosse stick (with the fainter stars being the handle and the brighter clump being the netting). In the central and northern parts of the cluster, along the Eiffel Tower, are two blobs of dark nebulosity: an 8′ x 4.5′ chunk toward the cluster’s middle, elongated SP-NF, and a larger, bowling pin shaped one (15′ x 5.75′ at widest, e.g. on the NF end) that runs parallel to the first. The larger of these dust blobs is not quite as opaque as the smaller. There’s also a separate chunk of dark nebulosity between the P edge of the Eiffel Tower and the “lacrosse stick”, most visible near the handle of the stick. There’s a 6th-magnitude star on the SF edge of the field that’s the brightest in the field, and there’s a double star on the F edge whose primary is NP the secondary by 20″ [magnitudes??].
(H) NGC 6645 (Sgr): This is a fantastic and underappreciated cluster! It’s immediately identifiable as a cluster, being pretty well detached from the surrounding Milky Way. The cluster is a large spray of stars, perhaps more than a hundred, most of them in the 11th/13th-magnitude range. The most obvious feature of the cluster is a circular void at its center, 3.5′ across, and ringed with a good number of 11th– and 12th-magnitude stars; the void itself is inside a “Hercules keystone”-type trapezoid of which all four corners are multiple stars: the star to the S is a triple; to the SF is a double; to the NF is a very unequal double (of a 13th-magnitude star and a threshold star); and to the NP is a dim double. There are also doubles on the P and F edges of the central void. The cluster branches N, SP, and NF from the void. The NF branch is dominated by a trio of brighter stars, but otherwise this branch is the weakest of the three; it terminates near an 8.5-magnitude star. The SP branch contains most of the stars and much of the unresolved background glow; it’s also the longest arm at 10′. The N branch is 5.5′ long. The whole cluster looks like a Greek letter lambda (λ), with the top of the letter being the SP arm, or perhaps a distorted mantel clock. Off to the NF end there is a large trapezoid of 7th/8th/10th-magnitude stars. N very slightly F the cluster by 19′ from the central void is the brightest star in the field, which is 7th magnitude and yellowish-white. Just on the F edge of the field (21′ from the cluster) is a 9th-magnitude star.
NGC 6649 (Sct): temps have definitely gotten cooler within the last half hour. This is a small compact cluster which I mistakenly thought to be a Herschel and had apparently thrown into my observing list under that mistaken assumption. Not a problem, though, as this is a very interesting little cluster. It’s a small (6′ x 5.5′) pentagon with 5′ extensions that stretch to the SF and SP; it looks for all the world like a starry, miniature state of Alaska. The cluster contains perhaps fifty stars and much unresolved starglow within the pentagon, and appears to be encircled by dark nebulosity given that there’s very little of note in the field beyond the cluster’s periphery (and we’re in Scutum, so the field should be very rich). The brightest star in the cluster is an 11th-magnitude star on the SP corner of the pentagon; the second-brightest is 12th magnitude and on the SF corner. Beyond the cluster, there’s an interesting double 17′ SP the cluster lucida; the 12th-magnitude secondary is 20″ P the 9th-magnitude primary. 20′ SF the cluster lucida is an 8.5-magnitude star.
VI. We were back at Eureka again the next night. Although the skies there are rarely as crisp as they are at Eagle’s Ridge (in part due to the latter’s higher elevation), the dew forecast at Eureka and the shorter drive had greater appeal than the more-difficult drive to Eagle’s Ridge. Having done the latter drive several times recently, it was no loss to avoid it this time.
And yet the skies were a bit murkier than the predicted forecast. It was hard not to second-guess the decision, although of the four of us present I think we all were leaning toward Eureka anyway. Amid the sky-haze, we did get a fine display of anti-crepuscular rays to start the evening off, and the conditions eventually ended up being pretty decent.
And so we “went to work.”
NELM: not checked
WEATHER CONDITIONS: temps falling to mid 50s; air still, considerable dew
Others present: JO, Dan B, Jeff P
NGC 6256 (Sco): It’s probably a bit too early in the evening for this one, as the sky isn’t 100% dark yet, but here we are. Another one of those unaccountably-missed NGC globulars I’ve been trying to catch up on. This one definitely doesn’t fit into JO’s “Big, Bold, Bright, & Beautiful” category—it’s quite difficult for an NGC globular, maybe among the top ten most difficult NGC globulars. It’s quite an odd one, too, elongated P-F, 1.75′ x 1.5′. There’s not even a hint of granularity possible, nor any particular central concentration to note (forget about getting a Shapley-Sawyer class!); it’s just an evenly-illuminated glow, somewhat akin to a Palomar cluster. The cluster is in the middle of the long side of a triangle of 12th-magnitude stars: one each 3.75′ from the N and S of the cluster, and one 4′ F very slightly N. P the cluster is a group of 12th/13th-magnitude stars, consisting of a small right triangle and a 7′-long N-S line of four stars. The hypotenuse of the right triangle is 3′ long and the triangle precedes the line of stars by 2.5-3′; triangle and line together look a bit like a miniature Coathanger. The right-angle vertex of the triangle is the farthest of the group from the cluster (10′ P slightly N). The brightest star in the field is 9th magnitude and is 19′ S of the cluster.
(H) NGC 6451 (Sco): The oddly-named Tom Thumb Cluster is pretty impressive, actually. Its basic pattern is diamond-shaped, with a 6′ major axis extending NP-SF and a 5′ minor axis running S very slightly P-N very slightly F. The majority of the stars and unresolved cluster glow run along the minor axis, especially from the star at the end of the minor axis S very slightly F to an 11th-magnitude star; the fainter stars and cluster glow run in a zig-zag between those two stars. The star at the SF end of the major axis is a very close double [details??]. NF the main body of the cluster is a group of four in a very tight triangle with an extra star SF the star at the S vertex. This is a very attractive cluster, quite well detached from the Milky Way, quite rich, with a magnitude range from 11th magnitude and fainter, down past the limit of resolution. The region around the cluster is somewhat barren of faint stars or Milky Way glow, with a few 11th-magnitude stars around but little else (certainly not much that’s fainter). 11′ S slightly P the cluster is either another cluster or a detached clump of Milky Way; it’s 2.5′ diameter and has a scatter of 13th/14th-magnitude stars over some unresolved background glow. A couple of more-obvious stars are on the P side of this clump and a few on the NF edge. SP this clump is a 7′-long line of seven stars ranging from 11th-14th magnitude and running NP-SF. A prominent double star lies just on the S edge of the field; this has a 7th-magnitude primary and a slightly-ornage 8.5-magnitude secondary S of the primary by 12″. This double star is the brightest star in the field.
(H) NGC 6624 (Sgr): Another globular that I missed during my survey, and a Herschel to boot. This cluster, unlike NGC 6256, is quite bright, reasonably large, and fairly concentrated—it’s not unlike a smaller, fainter M80. The cluster is 2.25′ diameter and perhaps a CC of 4. It has a small but bright core region, 0.5′ across, that isn’t resolved; and the halo is nicely granular. NGC 6624 is in the middle of a triangle of 11th/11.5-magnitude stars, the closest of which is due P the center of the cluster by 1.75′ (this star may actually be double). Another 11th-magnitude star is SP the cluster by 3.25′, and there’s an 11.5-magnitude star 2′ F very slightly S of the cluster. There are also two chains of stars that lead NF from the cluster: the first includes the cluster itself and has two 10th-magnitude stars in it (one 4.5′ NF the cluster and the other 3.25′ NF that star); 1.25′ N very slightly P the first of the 10th-magnitude stars is a 12.5-magnitude star. The other chain begins 7′ N slightly P the cluster, with a 10th-magnitude star; 2′ N very slightly F that star is an 11th-magnitude star, and N very slightly F that star by 5′ is another 11th-magnitude star which is 13′ N of the globular; this second 11th-magnitude star is also the brightest in a triple (or small group), with a 12.5-magnitude companion 0.3′ P very slightly N and a 13.5-magnitude star 0.67′ SF the 11th-magnitude star.
(H) NGC 6894 (Cyg): Having frittered away a long stretch unsuccessfully looking for the Sharpless nebulae in Sagitta (the TriAtlas has them in the wrong positions!), I’ve found this lovely and underappreciated planetary nebula quite easily. It’s very obvious even without a filter, a smoothish glow with hints of annularity but no central star visible. The N edge seems a bit brighter than the rest. The nebula is 0.75′ in diameter with the O-III filter in, and the filter really makes it pop, heightening the sense of annularity and making the edge of the nebula seem distinctly brighter than the interior. The nebula sits in the middle of a ‘Y’-shaped pattern of brightish stars with one due N, one to the SF, and a small triangle to the P somewhat S: the star to the N is 9th magnitude and 7.5′ from the nebula, the star to the SF is 10th magnitude and 6′ from the nebula. The small triangle that makes up the other point in the ‘Y’ consists of a 9.5-magnitude star 7.5′ SP the nebula, which is the closest to the nebula and the F-most vertex of the triangle); the other two vertices are a 9.5-magnitude star 2′ N slightly P the first 9.5-mag star and a 12th-magnitude star 3′ due P the first 9.5-magnitude star. There’s also a wedge- or ‘V’-pattern of five stars N slightly P the nebula; the brightest star in this smaller pattern is at the joint of the ‘V’ and is 14′ N slightly P the nebula. The ‘V’ points toward the P edge of the field, and its sides (angled SP-NF and N-S) are both 2.5′ long. Two 8th-magnitude stars are tied for brightest in field: one SF the nebula by 21′ and the other P very slightly N of the nebula by 17′.
VII. Friday night (the 13th, naturally) found us doing an outreach gig just outside Springfield, Eugene’s “twin city.” This took place at the Dorris Ranch, a historical site and nature park that’s on the National Register of Historic Places. We had done public star parties there the last several years; even Mrs. Caveman had been involved with these in the past, but she was too worn out from work to be goaded into it this year.
The star party went well—there were perhaps forty attendees and a half-dozen or so telescopes. Being just outside of the city, the skies weren’t very good, but they were enough to show the planets and a few of the showpiece summer objects (M13, M11, M57, M27, etc.). Driving home, though, I ended up on the wrong end of a police car’s flashers.
“Evening, sir. Have you been drinking?”
“No, officer–just doing astronomy.”
“Astronomy. That’s a new one.”
I thought I was toast. As it turned out, astronomy must’ve been a decent-enough excuse, as he handed me back my license and insurance card and drove off without waiting for me to go (I assume “late Friday night” + “not knowing where I was going” must’ve seemed a bit suspicious to start, but not very serious.)
I’d been waiting for Saturday night for a while—we had been planning an excursion to Champion Saddle, the club’s third, darkest, and most-distant observing site, for a few weeks. Mrs. Caveman and I had stumbled across the site early in our tenure in Oregon, but that was by day; I’d never been there at night. I planned and packed for this excursion as if it was the Oregon Star Party itself, despite it being a one-night session.
The first mistake I made was being too amped up for it. As with OSP and Brothers, I was building up an expectation that would somehow have to be a letdown; without enough sleep (mistake number two), the adrenaline crash of driving to such a dark site would mean getting tired really fast. And this is, of course, what happened.
Mistake number three was bringing the 18″ scope and not the workhorse Bob the Dob. The clunkier scope, much harder to wheel around and view through, proved to be too much for a tired caveman to work with, especially given the ridiculously-faint targets that I’d filled my evening’s observing list with (mistake number four). Many of the objects were flat galaxies, Arp peculiar galaxies, Palomar and Terzan globulars, and the like—a list designed for large apertures and dark skies.
We arrived just at sunset, having stopped in the nearest small town (Dorena) to visit a friend of Jerry’s who was offering his yard up as a potential observing site. The mosquitoes were a problem from the moment we got out of our vehicles; the sound of buzzing—sometimes in harmonic fifths—is pervasive throughout the one recording I made. So DEET it was.
The horizons at Champion Saddle were better than at Eagle’s Ridge, although the east and north/northwest were compromised by mountains. Yet as the sky began to darken, it was clear that this was an epic observing site, and should have been an epic observing session. The Milky Way became not just visible quickly, but detailed; stars almost seemed to turn on rather than gradually appear.
But I was tired already. Coming at the end of a long stretch of observing nights, and requiring a lot more concentration on the long, twisty drive out, the experience of preparing and getting here was already a bit too much. By midnight, I had struck out on almost all of the targets on my list that were post-meridian, and I was starting to lose parts of the Milky Way to the horizon as well. (I think the exception was UGC 9780, a flat galaxy in Boötes, although I didn’t take notes on it.) It was probably a good thing I was set up at the far end of the group, as I was grumbling and swearing enough to harsh the entire group’s mellow. (Shades of the run’s first night, at Eureka, with the 18″ scope.)
CHAMPION SADDLE (N43° 34.714, W 122° 38.026)
MOON: 2 days (4% illumination); set at 10:23 PM
NELM: not checked
WEATHER CONDITIONS: temps falling to mid 60s; air still, no dew; vicious mosquitoes
Others present: JO, RA, AG
Observation : 18″ f/5.5 Dobsonian, 14mm ES 82˚ and 10mm Delos eyepieces (178x, 0.5˚ TFOV; 250x, 0.3˚ TFOV)
I stopped what I was doing, settling onto my chair and taking a few minutes to stare at the Milky Way. Although the dark nebulae weren’t as spectacular as on that night at Eureka—the Dark Horse was still visible, but not quite as clearly here—the glimmer of countless stars along the Milky Way itself was simply breathtaking. It didn’t look real. Star clouds could’ve been real clouds, as tangible and close as they looked. I felt a shiver of awe. Not even OSP or Brothers had skies like this. With the exception of a light dome to the north-northwest, the sky looked the way it might’ve looked when my Australopithicene brethren stalked the East African Rift Valley. The visible planets shone with a cold, unflinching light, clearly foreground objects set against the stage tapestry of the galaxy’s spiral arms.
This momentary reset helped me to settle down, and I searched through my list for an object near the meridian on which to focus my energies. The one I chose had been a bête noire for years, and it took several checks against the entry in Alvin Huey’s superb globular-cluster guide to verify the field. And there it was:
Arp 2 (Sgr): Having failed to find any of the other difficult targets I’ve set myself for this occasion, I’ve managed to eke out a win here, in my four-millionth attempt at this nasty little globular. It’s way down to the limit of the 18″ scope’s altitude motion and exceedingly faint, but most definitely there (if mostly an averted-vision object). Not much more than a brutal 2′ haze that’s hard to hold steady. In the 10mm Delos, the cluster is harder to pick out but easier to hold once found. No concentration is discernable. There are several faint field stars near the cluster’s periphery and the field itself is crowded with stars of a wide range of magnitudes. On the S side of the field, stretching from the P side of the field to S of the cluster to the SF side of the field is a large arc of stars; the arc begins at a 10th-magnitude star 13′ P the cluster and sweeps S-ward, through many 11th/12th-magnitude stars, including a small “sub-arc” of five stars 12′ S very slightly F the cluster, the middle star of which has another of equal magnitude to the N slightly P by 0.75′. Another arc lies NP and N of the cluster; this one only has three stars, but it frames the cluster, and at its NF end is a small isosceles triangle of four 13th-magnitude stars (the extra star is in the middle of the long edge of the triangle, which is the N edge. [size of triangle?]
Although buoyed by conquering this particular demon, I stayed away from most of the rest of the fool’s list I’d made; instead, I turned the 18″ scope toward as many of the eye-candy objects of summer that I could. Each was stunning, no matter how many times I’d seen them. M8, M20, M13, M15, M16, M17, the Veil Nebula, M10/12/14/9 in Ophiuchus, even NGC 7479 in Pegasus… the dark skies and larger aperture made them each seem like new objects I’d never seen. M20 (the Trifid Nebula) in particular took on an added measure of brilliance beyond any of my previous observations, the dark lanes three-dimensional in front of the rose-flower shape of the hydrogen emission nebulosity, the multiple star at the nebula’s center shining brightly through and the reflection nebulosity to the north a cloud of easy cirrus.
Jerry packed up first, as he had a (highly-publicized!) solar star party to conduct at Alton Baker Park early Sunday afternoon—and just that quickly, the night at Champion Saddle was over. Robert (and Alan, who had hitched a ride with Robert) followed shortly after Jerry. Despite the cosmic splendor, I had no hesitation in packing up as well; Robert helped me wrangle the big scope’s heavy mirror/rocker box combo into the back of the Caveman-Mobile before leaving, and I stowed the rest of the gear around it with a semblance of order.
The drive home was the most uncomfortable 100 minutes I’ve ever spent at the wheel. I went through a can of Dr. Pepper in about ten minutes, trying to get enough caffeine in my system to not fall asleep on the treacherous and winding highway around Dorena Lake, with the sky brightening quickly and traffic increasing with the daylight. Much of the drive occurred somewhere on the knife-edge between sleep and primal survival instinct, threatening the former with every passing mile. But when I needed stroke of good luck, I got one—Isolda, my GPS, led me into an out-of-the-way neighborhood somewhere beyond Lowell, necessitating a lot of backtracking to get back to the highway; we had set the GPS preferences to “include backroads” during our geology expedition weeks earlier, and I hadn’t changed it back. The upshot was that I spent quite a lot of time cursing at the GPS, the roads, and traffic in general, and the adrenaline from this self-inflicted burst of road rage kept me just alert enough to finish the drive and swear I’d never do it again without sleeping for several hours beforehand.
VIII. I didn’t want to end the July run on a down note. Sunday was out; I was asleep Sunday night before 10:00, and had refused to entertain the notion of observing that night no matter what the forecast (or the cajoling of fellow observers) held. I promised Mrs. Caveman that I would be done with the July run Tuesday night, regardless, and the Moon would be an intrusive presence by that point anyway. So when Dan B suggested a trip to Eureka Monday night, I planned for it to be July’s last hurrah.
Moonset was scheduled for 11:35; I arrived at Eureka at about 8:30. Dan followed shortly, his daughter and her friend in tow. Although I still had my summer Herschel list to work from, I spent time with a number of other objects as well—including a couple of open clusters that I mistakenly had marked as Herschels on the laminated pages of Sky Atlas 2000.0. With a trip to Hawaii scheduled for two days later, Dan wasn’t planning to stay as long as usual, and having spent nine nights out of eleven doing astronomy, I understood perfectly well.
MOON: 4 days (18% illuminated); set at 11:35 PM
TRANSPARENCY: 6 (predicted 8); MW bulges into M9/Dark Horse region and toward Beta Lyrae
SQM: not checked
WEATHER CONDITIONS: temps falling to mid 60s; quite breezy, some dew
Others present: Dan B, Ruby, Jasmine
NGC 6337 (Sco): The Cheerio Nebula. Quite difficult at the moment, as it’s down really low in the sky—I’m sitting on the ground—and the transparency down here sucks. I found the nebula without a filter, catching it with averted vision as it swept into the field. Even with a UHC filter, the annulus is still difficult, as the center isn’t dark enough, although averted-plus-filter does reveal traces of annularity (especially along the N edge). The nebula is about 45″ across. I know that there are multiple stars across the center but they’re unresolved without the filter and invisible with it. There is a 12th-mag star visible 0.5′ from the outside S edge of the nebula’s halo; the nebula is inside a small diamond of stars that includes this star, a 10th-magnitude star SF the nebula by 3.5′, a 12th-magnitude star F slightly N of the nebula by 2′, and another 12th-magnitude star NP the nebula by 2.5′. P slightly N of the nebula by 9′ is the S-most of a pair of 10th-magnitude stars, with the second NP the first by 1.5′. S and P the nebula is an arc of three 10th-magnitude stars: one to the P slightly S of the nebula by 5′, one due SP the nebula by 6.5′, and one due S of the nebula by 9′. The field’s brightest star is the primary of a double/pair that is N of the nebula by 18′; it has a 10th-magnitude companion due S by 30″.
(H) NGC 6755 (Aql): This is quite a fascinating open cluster, full of smaller clumps of stars. It’s reasonably-well detached from the Aquila Milky Way, and quite rich; there are perhaps eighty stars here, plus a fair amount of unresolved starglow present. The brighter cluster stars are in the 10.5-magnitude range and range down past the edge of resolution. The cluster proper is bounded inside a triangle of 10th- and 10.5-mgnitude stars with a 10th-mag star to the P, a 10.5-magnitude star to the N and a 10.5-magnitude star F; the long side of the triangle runs P-F. Along the F side of the triangle is a line of brighter stars that connet the F and N vertices, but the other two sides of the triangle are less defined. The cluster consists of three individual clumps, each of which could have its own catalogue number. The N-most clump (#1) stretches 6.5′ x 2.5′ SP-NF and has an 11th-magnitude star on its N edge; this clump contains two smaller clumps: a 1′ diameter “sub-clump” (1A) on the SP end and a larger sub-clump (1B) on the NF end of the main clump, with a gap of about 1.25′ between the two sub-clumps. The smaller (SP) sub-clump has a 12th-magnitude star on the N slightly F end that is the N vertex of a very small triangle around which this sub-clump is visible; this sub-clump contains six stars and some unresolved glow. The larger (1B) sub-clump is pentagonal, with its major axis running SP-NF. South of clump #1 is another two-part clump, with one sub-clump to the P (2A) and one to the F (2B… or not). 2A is the brighter portion here and is trapezoidal in shape, with a 10.5-magnitude star at the P tip of the trapezoid; this sub-clump is 2.25′ in diameter and has seven visible and a host of unresolved stars. There’s a gap between 2A and 2B to the F very slightly N. 2B is also trapezoidal, about 2.25′ x 1.75′. The SP vertex of the trapezoid is actually a very small group in itself, while the NF vertex is a double star. Most of the other stars in 2B are in the 13th/14th-magnitude range. 4′ due S of the space between 2A and 2B is main clump 3, the smallest of the three clumps in NGC 6755 at 0.67′ diameter. This clump has a small square of 14th-magnitude stars superimposed over the top of it, and not much of this clump is resolvable. This clump is just outside of the cluster’s “bordering triangle,” to the S, while both parts of clump #2 are just on the S side of the triangle.
(H) NGC 6756 (Aql): This cluster is only 32′ NF NGC 6755, and is also a small unresolved clump of stars. My first thought was that I’d actually swept over NGC 6760, the brightest of Aquila’s three globular clusters, as NGC 6756 presents a globular-like face, with a brighter knot of stars on the NF side seeming rather like a core, and it’s highly detached from the Milky Way background. Averted vision brings out many background stars amid the starry haze. There are perhaps 30 stars tightly packed into this 3.5′ diameter cluster, representing a fairly-broad range of magnitudes. Aside from the knot on the NF side, the cluster’s most-prominent feature is an arc that runs S of the knot from SP-SF; the brightest star in this arc is 13th magnitude and is SF the knot by 1.75′. SF the cluster by 11′ is a 9th-magnitude star. NP the cluster by 14′ is the brighter of a pair, the brighter being 11th magnitude and the fainter (P the brighter by 0.5′) being 12th-magnitude; this pair forms the joint of a ‘V’-shaped asterism that branches N slightly F and NF from the brighter of the pair. 4′ N of the cluster is another double/pair, the primary of which is 12.5 magnitude and the secondary (due P by 0.3′)of which is 14th magnitude. NF the cluster is a large lowercase ‘y’ pattern of twelve stars, the majority of which are 10th/11th magnitude; the ‘y’ stretches from SF-NP in the field and also to due N, and with the SF-NP branch 15′ long and the N branch 6′ long. An 8.5-magnitude star—the brightest in the field—lies SP the cluster by 15′.
NGC 6738 (Aql): This is a large cluster amid what looks to be a tangle of dark nebulae, the most prominent of which runs parallel to the F side of the triangle. The cluster is pretty obviously an entity unto itself, with some sixty stars ranging from 7.5 magnitude down to magnitude 13. A 7.5-magnitude star on the SF end of the cluster is the lucida. The F side of the triangle is defined by eight stars in a 30′ line up to an 8th-magnitude star that is the N vertex of the triangle; P slightly S of that star by 17′ is a pair that forms the third vertex, with the pair consisting of a 10th-magnitude star and a 12.5-magnitude star that’s 0.67′ SF the brighter. Along the NP edge of the triangle is a pattern that consist of a small isosceles triangle with fainter stars bounding it to the P and SF. A jagged line of nine stars runs across the cluster’s middle from P to F; the P-most trio are outside the edge of the triangle, the remaining six inside (patterned 3-2-3-1, with the ‘1’ being a 9th-magnitude star on the F edge of the cluster).
NGC 6709 (Aql): Another triangular cluster; another one I mistakenly thought was a Herschel object. This one is smaller than 6738: 11′ on the S and P sides and 13′ on the F side (which runs NP-SF). It’s also quite obviously a singular entity, with 75 stars ranging from 9th magnitude to 14th. One 9th-magnitude star is the SP vertex of the triangle; another is paired with a 9.5-magnitude star (the brighter star 0.67′ SP the fainter. This pair is part of the SF vertex of the triangle, which is a triangle unto itself: the star on the SF tip of this tiny triangle is also a double/pair of 10th– and 12th-magnitude stars, with the fainter SP the brighter by 0.25′; the 9th/9.5-magnitude pair is due P this double by 1.25′. (This smaller triangle is the cluster’s most-obvious feature.) The NP vertex of the “main” triangle is 10.5 magnitude. Along the F edge of the triangle, 4′ from the 9th/9.5 magnitude pair, is a knot of stars running SP-NF; this is 5.5′ x 2.75′ and contains the largest concentration of unresolved stars in NGC 6709. On the SP and due P of the cluster are small knots of dark nebulosity that are pretty obvious. The cluster also has several chains of stars, including one that runs parallel with the P side of the triangle, on the inside of the triangle. There’s also a small knot of stars 16′ SF the cluster; this contains 8 stars.
(H) NGC 6824 (Cyg): Not the brightest of galaxies, but there aren’t that many in Cygnus anyway. This one is small but pretty obvious, 1.0′ x 0.67′ and elongated SP-NF. It has a diffuse halo with a slightly-brighter small core and a stellar nucleus that requires averted vision for a decent view. A 14th-magnitude star lies just outide the halo to the S, about 0.67′ S of the galaxy’s nucleus. There’s a bright double/pair 4′ due N, 9th– and 12th-magnitude companions separated by 15″. NF the galaxy by 2′ is a 14.5-magnitude star with a 12.5-magnitude star to the NP; these form an obvious triangle with the star just S of the galaxy’s halo. SP the galaxy by 13′ is a 9th-magnitude star, with another 9th-magnitude star S very slightly P by 3.5′. S slightly F the galaxy by 19′ is the brighter of a pair consisting of 7.5- and 10th-magnitude stars, with the fainter 0.67′ S very slightly P the brighter. F very very slightly N of the galaxy by 18′ is an 8th-magnitude star which is the NP vertex of a triangle; SF that star by 7.5′ is a 9th-magnitude star, and S of the 8th-magnitude star by 12′ is a 9th-magnitude star.
(H) NGC 6802 (Vul): A superb cluster that lies off the F end of the famous Coathanger. The bluish 6th-magnitude star at the F end of the Coathanger is in fact visible just on the P end of the field, 20′ P the cluster. NGC 6802 is one of the nicer NGC clusters, a well-detached and –defined 6′ x 2.5′ spray of no less than a hundred stars elongated N-S. The stars in NGC 6802 are mostly faint or just beyond resolution; the visible stars are mostly 13th-15th magnitude and the brighter ones seem to have congregated toward the N end of the cluster. The cluster is bounded to the NP and NF by double stars/pairs; 7′ NP the cluster’s NP corner is a 9.5-magnitude star with a 10th-magnitude star 1′ P very slightly S of it, and 6′ NF the NF corner of the cluster is a 10.5- and 11.5-magnitude duo with the fainter P very slightly S of the brighter by 0.67′. Due N of the cluster by 5′ is a 12th-magnitude star. S very very slightly F by 10′ from the cluster is a 10th-magnitude star. SF the cluster by 14′ is the brighter of a 9.5/12.5-magnitude pair with the fainter NF the brighter by 0.67′; there’s a 14th-magnitude star N very slightly P the 9.5-magnitude star by the same distance.
With NGC 6802, I closed the book on observing in July (at least as of this writing; with the Moon Full on the 27th, it’s unlikely I’d be coaxed back out until August). I did do two more nights of outreach during the month, both with my newly-refurbished 13.1″ Coulter Odyssey. My adjustable observing chair is in dire need of repair, and the Coulter still needs some work to make it as functional as it once was, so these projects will likely take up the rest of my astronomy time for the month (along with logging all of the July observations).
It had been an epic month of observing, easily the equivalent of a week at one of the major star parties where nothing but astronomy seemed possible. All but one or two nights this month had been clear (at least so far; the forecast shows nothing but sun and heat through early August). I hadn’t observed the huge numbers of objects that I’d done some past months, but the variety and quality of the observations made up for it, and some of the objects I’d seen had been on my list for years. And if August is as good as July, I’ll be out observing wherever the Caveman-Mobile takes me.