I. The end of August was supposed to bring the Brothers Star Party with it, but things didn’t quite work out that way. Instead, the weather forecast seemed to be telling us to find alternative vacation plans, and we did: two nights in Portland (for Mrs. Caveman and Cave-Offspring to see Malala Yusufzai, and to attend the superb production of The Lion King as it swung through the Pacific Northwest), then two in Seattle spending time with two of our best friends from our Illinois days. Even as the forecast for Brothers improved, I ended up not having any regrets about skipping it.
The previous week saw a number of us in EAS heading out to Eureka Ridge for a few clear nights, dodging the Moonrise as best as we could. These nights gave me a chance to make some more headway catching the few NGC globulars I hadn’t taken notes on, as well as digging further into the Astronomical League’s Planetary Nebula observing program. The skies both nights I went out weren’t perfect, but they were certainly good enough. I had knocked together a list of objects (five per constellation) for Brothers, but that would mostly have to wait, minus the objects I scavenged off of it.
I still haven’t gotten the EAS 18″ scope fixed, but Bob the (12.5″) Dob works pretty damned well by itself.
8/24-8/25/16
EUREKA RIDGE
MOON: 22 days (Last Quarter), rose at 12:07 AM
SEEING: 6
TRANSPARENCY: 7
SQM: not checked
NELM: not checked
WEATHER CONDITIONS: temps in low 60s, little dew; strong winds above, occasional gusts at ground level
Others present: JO, OG, FS
All observations: 12.5″f/5 Discovery truss-tube Dobsonian, 14mm ES 82˚ eyepiece (112x, 0.7˚ TFOV) unless otherwise noted
9:36
NGC 6342 (Oph): small, about 2.0′ across—slightly granular—middle 1.5′ is brighter core—comes to fairly abrupt edge—two main brightness gradients—just S is a 12th mag star just off edge of halo—with cluster centered, to NP and SP sides there are bright stars—one to NP is brightest, 6th mag—bright SP star is a pair, brighter of which is 8th mag, dimmer is 10th—due following cluster is another brighter star, 8th mag star which has a 12.5-mag companion star preceding it by 1.5’—closer in are two more stars preceding cluster by 10′ NP and SP—star to SP is 11th mag, star to NP is 11.5 mag—really bright star is on edge of field, much closer is the other pair NP and SP—NF cluster is a squiggle-pattern of stars—[satellite through field]—cluster is about 6 CC [actually 4]—medium concentration—doesn’t resolve—in averted there are a couple of brighter stars on edge of core, but they don’t “pop”—cluster could be mistaken for elliptical galaxy aside from granulation—in averted, on NF side, between edge of core and edge of halo is one distinct threshold star
9:49
NGC 6356 (Oph): hop skip and jump N of 6342—much larger—3′ core, halo extends to about 3.5’—to P side and slightly N by 18′ is an 8th mag star—due S by 10′ is a 10th mag star—these are brightest stars in field—attractive field in Milky Way—cluster not quite granular, more powdery around edges—to P side, especially in averted, looks like a few stars on edge of halo outside resolution—pretty tight globular, maybe CC 4 [actually 2]—considerably brighter than 6342, maybe 9th mag—easy-to-look-at object—in middle of smattering of stars on N side running almost all the way across field from brightest star, a string of mostly 10th/11th stars that run most of way across field, not quite straight—overlooked object!
10:29
IC 4593 (Her): White-Eyed Pea—found w/14mm, walked over it—in field of very interesting double star which caught my attention—very very small planetary, a couple of ” across—in 10mm a little fuzzier, easier to see—looks like central star is visible, with a fringe of nebulosity around it—to NP side by 7′ is a 9th mag star—double star is SF nebula by 12’—double has 11th and 13th mag components, separated by 15″, about size of nebula—couple of other brightish stars (11th/12th mag) in field, about 12′ and 15′ SF nebula—w/UHC: definitely brightens nebula, which becomes considerably larger, outer fringe much more visible—about 18″ across with 10mm—no real discernable shape beyond roundish—nebula now brightest object in field with UHC—definitely non-stellar, fuzzy—w/OIII: very similar to UHC view, hard to tell difference other than sky darker in OIII—seeing too poor for 6mm Radian view
10:50
NGC 6814 (Aql): face-on spiral, and looks like one (14mm)—galaxy is 2.25′ diameter—no stellar nucleus even in averted—dim core that’s quite small—on NP edge of halo is a 13th mag star—to SF edge of halo, off by about 1′ from halo is 14th mag star—to NF edge is threshold star that comes and goes with seeing—galaxy in middle of diamond pattern of 13th mag and dimmer stars that’s 5.5′ on its major axis, which is extended NP-SF—galaxy in rich field—NP galaxy by 9′ is a 9th mag star—galaxy has “face-on” brightness profile—halo slightly extended to N, but not S, so doesn’t look symmetrical—core seems off-center to S because of extension—may be star involved in halo just N of core, probably not nucleus—in averted, star on F side of halo makes galaxy look “stretched” in that direction
11:17
NGC 6772 (Aql): found in 14mm with no filter—not a hint of central star—due F nebula by 18′ is 8th mag star—P and slightly N by 9′ is 10th mag star—planetary dim but obvious w/no filter—1.5-2′ across—averted hints at some annularity—in averted, P side slightly brighter than F side—w/OIII: nebula definitely brighter on P edge—not quite round, extended to N—a little flatter on F edge—definitely a darker void in middle, a bit toward S side—not circular, but hard to define shape—has brighter structure that doesn’t go all the way to edge, and faint edge that drops away into background—inner region is brighter but not well defined—w/UHC: nebula not as bright as in OIII, and structure is more subtle—dark region in nebula still visible, but inner structure not as detailed—still getting idea that nebula extended to N—less-detailed view, but better than unfiltered view—nebula better defined on edge of inner region, but not as much as in OIII—(11:36) in 10mm, not much more detail than in 14mm—w/UHC: a bit more pronounced annularity, ring itself may be thick—still seeing extension to N slightly P edge of nebula—in averted annularity a little bit more prominent, but irregular—darkness in interior irregular-shaped—w/OIII: brighter but view is otherwise quite similar—definitely some sort of irregular annularity
12:01
NGC 7013 (Cyg): galaxy near Veil Nebula—fairly bright—small, just over 1.0′ x 0.75’—to N edge is 10th mag star, 2′ from edge of galaxy—to P edge of galaxy by 1.5′ is 13th mag star—to SF edge of galaxy by 2′ is 13th mag star—w/averted has almost stellar nucleus—bright core—elongated N-S—fairly rich Cygnus field—lots of 10th/11th mag stars—galaxy in little triangle—not an overly impressive galaxy, but brightest in Cygnus Milky Way
II. The next night was a continuation, with the Moon rising slightly later in the morning:
8/25-8/26/16
EUREKA RIDGE
MOON: 23 days (43%), rose at 12:54 AM
SEEING: 6
TRANSPARENCY: 6
SQM: not checked
NELM: not checked
WEATHER CONDITIONS: temps in low 60s, little dew; strong winds above, occasional gusts at ground level
OTHERS PRESENT: JO, OG, BH
All observations: 12.5″f/5 Discovery truss-tube Dobsonian, 14mm ES 82˚ eyepiece (112x, 0.7˚ TFOV) unless otherwise noted
9:47
NGC 6366 (Oph): very large, very diffuse globular—in field with 5th-mag star—globular is 5-6′ diameter—very loose—CC 10, maybe 11—on P side, a pair of bright stars separated by 4’—N-most of pair is 10th mag, S-most 11th mag—on S edge of cluster’s halo, separated by 1′, is pair of 12th mag stars—to NF side by 2′ outside of halo is another 12th mag star—cluster has just a slight bit of central brightening, need to get naked-eye star out of field to see—in averted, cluster is granular—couple of cluster stars just on threshold of vision—line of brighter cluster stars is elongated NF-SP—huge cluster, very difficult and faint—almost like NGC 5897 but dimmer—impressive in size—due F on edge of outer periphery is a 14th mag star
10:07
NGC 6235 (Oph): result of long search w/o finder—3.5′ diameter, not round—elongated PNP-FSF—almost triangular shape—inside isosceles triangle of 12th mag stars—long side of triangle is 8′, two other sides 6’—long side oriented almost due P-F—other star is almost due N of cluster—cluster is diffuse—core makes up about 90%, so halo is just fringe—inner 1.0′ has scattering of threshold stars across it—CC 8 [actually 10]?—just on P and F edges of field are two brightest stars—star on P edge is 9th mag, star on F edge is 8th mag—core is irregular shaped, stretched N-S a bit inside halo—in averted, one brighter star in middle of core
10:54
NGC 6544 (Sgr): moderately-bright, loose globular—oblong—satellite tumbling through it—elongated NP-SF across core—about 3′ across in m.a.—core about 2.5′ x 2.0’—in loop of 11th-14th mag stars—to SF by 9′ is 10th mag star—granular, especially in averted—has a smattering of stars across middle, maybe 10 stars in averted—just on verge of resolution—CC 8 [actually 5; all over the map with these]?—pretty loose, pretty diffuse—overall catchy globular—SF by 20′ is big double star of 11th mag components separated by about 1’—very faint satellite moving very slowly N-S through field
11:02
NGC 6553 (Sgr): super-diffuse globular—powdery looking—4.5′ across—on SF side of field is 9th mag star—globular very powdery, very fine—on NP edge of cluster is a 12th mag star just on edge, maybe just inside halo—fairly loose concentration, CC 8 [actually 11]—in averted, looks like trying to break up into resolution—more spacious “feel” to concentration, like space between stars almost visible—pretty round cluster, maybe slightly elongated NP-SF a tiny bit
11:29
NGC 6781 (Aql): large planetary—2.0′ across—no central star—looks somewhat annular, S edge is brighter—central “hole” seems to be to N slightly F edge, off center—pretty round, one of rounder planetaries—almost due S by 18′ is 9th mag star—almost due F by 20′ is 10th mag star, these are two brightest in field—a number of other fainter stars in field—w/UHC: impression of annularity still valid—S edge is brighter, N edge more diffuse—annularity more concentrated toward N side—w/OIII: aside from having more contrast, not doing much better than UHC—annularity harder to detect in OIII than in UHC (11:48): in 10mm: nebula has threshold star just on N edge that wasn’t visible in 14mm—star really comes and goes—circular shape has well-defined edge, but has a few-arcsec thick halo around outside that’s diffuse/fuzzy–w/UHC: threshold star dissapeared—annularity more obvious than in 14mm—nebula seems more circular, although annularity still off-center
As with the previous night, the rise of the Moon cut our observing short.
This ended August’s observing–I had begun the month at OSP and ended it back where I really belonged. It also ended the summer’s observing; with New Moon week already over as I write this, and a busy work schedule for September, it will be near the month’s end before I can do any serious deep-sky work again. By that point, Scorpius, Ophiuchus, and the early-summer constellations will be well on their way out, and the rich galaxy fields of the autumn will be working their way west toward the meridian. This was always my favorite time to observe in the Midwest. It remains to be seen how autumn’s stargazing will turn out here in the Pacific Northwest.
The Unfrozen Caveman Astronomer 