February 12th brought a pretty good forecast and a good opportunity to get out and do some more observing; my work shift for the next day had been canceled, so I could stay out as late as I wanted to. The below-freezing temperatures weren't really an issue. What became an issue were the gusty winds that rose up an hour or so into the session and made the cold a much more unwelcome experience. As a result, I ended up leaving earlier than I'd intended to.
As usual, I was working the Herschel 400/HII lists. I've made much more headway on the latter recently, and have 30 more objects there than on the H400. I'm amused at the thought of finishing the HII before the H400 for some reason--and at the thought of finishing the Herschels before formally finishing the Messiers (I've seen all the Messiers multiple times; I just haven't taken formal notes on all of them yet, and I don't count an object as "seen" until I've taken notes on it).
One for the "Tiny Blunders" thread, I suppose: I was aware of the supernova [SN2018gv] in NGC 2525, and as the galaxy was on my list, I'd intended to collect photons from the supernova. I usually sketch extragalactic supernovae to make a permanent record of these transitory events, but I wound up forgetting to pack my sketching gear with me (I even looked right at it as I was doing a final run-through in the garage). Even dumber, when observing the galaxy, I never thought to call up the February Supernova thread to check the photograph of the galaxy showing the supernova. So I tried to take notes that included every star in the galaxy's vicinity, and ended up thinking that I'd caught the supernova. However, after looking at the photos and comparing them with my notes, there was enough uncertainty that I eventually had to conclude that I couldn't be sure which star in my notes was the supernova, and therefore couldn't claim with certainty that I'd seen it. While I'm sure photons from supernova made their way into my primitive brain, I won't count this one as a sighting. (Hopefully, it'll still be bright when I next get clear skies and can remember the sketch kit.)
Although conditions were good at 45* altitude, they were much poorer down in the gunk where I spent much of the night; some of these objects barely cleared the mountain ridge that marks the southern limit of observability here. As a result, my magnitude estimates are way off on field stars around the more-southerly objects. And many were indeed southern; NGC 1532 was only a field-of-view above the edge of the ridge when I observed it.
NGC 1679 and the NGC 1532/1531 pair aren't Herschel objects, but 1532 had been on my target lists for some time; even diminished as it was by the low altitude, it was still impressive, which was why it was on my list in the first place. NGC 1679 was the only bright object of any sort in Caelum, and as I've had the strange goal of observing a galaxy in every constellation visible from my observing sites, it was one that had additional "value" beyond being a bright galaxy in desperate need of being observed. (Yes, I know observing a galaxy in every constellation is a weird goal. I never claimed to be normal.)
As usual, a full writeup of this session, along with Australopithicene philosophical musings, can be found at the blog address below. As a parting note, I'll throw in that it's now impossible to say "NGC 2525" without singing it as a parody of "In the Year 2525."
EAGLE’S RIDGE SPUR ROAD (43° 48' 17.9496'' N, 122° 42' 45.6912'' W)
MOON: 28 days; 4% illuminated, rose at 6:01 AM
TRANSPARENCY: 7, much worse at lower altitudes
SQM: not checked
WEATHER CONDITIONS: temps in low 30s/high 20s, considerable breeze starting from 8:30; frost on exposed gear by 7:30
Others present: none
All observations: 12.5″ f/5 Discovery truss-tube Dobsonian, 14mm ES 82˚ eyepiece (112x, 0.7˚ TFOV) unless otherwise noted
NGC 1187 (Eri)—not fully dark yet—big, diffuse, not particularly easy glow—forms a squashed pentagon with four stars—very poorly defined—has a measure of central brightening but no visible nucleus—brighter core region—inclined spiral?—elongated NP-SF—3.5' x 2.5'—poorly defined so hard to tell where halo ends—inner region is about 1.0' x 0.67' and comes gradually to halo—4.5' NP from center of galaxy is a 9th-mag star; S slightly P that star by 4' is a 12th-mag star; S of that star by 5' is an 11th-mag star; an 11.5-mag star F and very slightly S that star by 3.25'—galaxy is NF vertex of this pentagon—pentagon elongated major axis N-S—just outside edge of field, 26' SF galaxy, is a 10th-mag star—N of galaxy by 19' from galaxy's center is a 9.5-mag star
NGC 1679 (Cae)—a bit of a wish fulfillment—very low in sky, barely cleared top of the ridge—could easily overlook, but definitely noticeable—not a threshold object—elongated mostly N-S, maybe N very slightly P-S very slightly F—very diffuse and weakened by altitude—decent-sized—a little bit of irregular central brightening, an odd shape—maybe a very faint stellar nucleus flashes in averted—has a 14.5-mag star on NP edge of halo that makes it hard to see if there's a nucleus or not—threshold star on SP edge of halo—2.25' x 1.75'—[very bright satellite through NP edge of field]—difficult halo to define—P and a little bit N of galaxy by 6' is the more-southern of a pair of 11.5-mag stars; other in pair is NP the first; separated by 2'—NP galaxy by 5' is a 14th-mag star—galaxy seems a bit triangular pointing to N very slightly P edge
NGCs 1332, 1325, 1319, 1315 (Eri)—1332: very bright—kind of a miniature NGC 7331?—elongated NP-SF—has a bright core and an obvious substellar nucleus—2.25' x 0.75'—well-defined—hard to get good focus this low—galaxy has threshold star just S of nucleus off edge of halo; star difficult to hold—N of galaxy by 8' is a very faint fuzzy glow, no discernable size, just very small weak diffuse glow, another galaxy? [??] Mainly averted object—NP 1332 by 22' is a 9th-mag star—field immediately around galaxy is otherwise pretty barren of stars—SP 1332 by 29' is 1325: considerably more difficult, partly because it has a brightish (12.5-mag) star on NF edge—galaxy elongated SP-NF—due F by 1' from center of galaxy is a threshold star—more diffuse than 1332—hard to tell if there's a nucleus because of star on edge—has some moderate central brightening—2.0' x 0.67'—another star NF the star on galaxy's edge by 3.75'; that second star is 13th-mag—S of galaxy by 8' is an 10th-mag star—P galaxy by 16' is a line of three stars, of which brightest is in middle; brightest is 12th-mag, other two are 13.5-mag—S of galaxy by 17' is another group of stars—back to line of three, which is about 3' long; brightest star is NP star next to it by 0.75', while third star is 2.25' the brightest—halfway between that line and NGC 1325 is 1319: very difficult glow of indeterminate size and shape—elongated NF-SP?—hard to hold steady in direct vision—[fogged up eyepiece]—0.75' x 0.5'—may have very very faint stellar nucleus—threshold star just off NP end of galaxy—back to line of three stars: 10' NP the brightest star in the line is a 0.75' glow (1315): has a 14.5-mag star SF galaxy by 1.5'—stellar nucleus that pops in averted—very diffuse galaxy, but brighter than 1319—a little more concentration than 1319—not well defined—easy to miss 1315 and 1319 without knowing they were there
NGCs 1532, 1531 (Eri)—way down low, on edge of ridge—seeing is very poor—1532: a huge galaxy, even considering conditions—elongated SP-NF—4.5' x 0.75'—has an obvious substellar nucleus and bright core—well-defined halo—no traces of bend in arms—1531: P 1532, very slightly N of 1532's nucleus—elongated P-F—0.5' x 0.3'—a wide sliver of darkness between two galaxies—doesn't have a visible nucleus—slightly brighter core—NP 1531 by 3' is a 14th-mag star—these galaxies are in a long triangle of bright stars; brightest (8.5-mag) is to NF of the center of 1532 by 14'; SP of 1532's nucleus by 7' is an 11.5-mag star and P the nucleus by 8' is an 11th-mag star; stars separated by 7'—F 1532 is a pair of 13.5-mag stars, separated by 2.5'
NGC 1353 (Eri)—seeing is better here than at previous galaxies—elongated NP-SF—has an obvious nucleus—brighter core—pretty well-defined, can see all the way to the edge—2.25' x 0.75'—2.5' SF from nucleus is a 13th-mag star—a 14th-mag star SP galaxy by 6'—NF galaxy by 15' is a pair of stars; brighter NP fainter by 3.5'; mags 11.5 and 12—F slightly N of galaxy by 13' is an 11th-mag star—pretty nice galaxy
NGC 1114 (Eri)—one of most difficult Herschels I've looked at so far—getting windier—galaxy a bummer—very very faint glow—elongated N-S—very very diffuse—poorly defined—2.0' x 0.5'?—almost no central brightening—from SF to NP, galaxy is third element in a line of four (including three stars)—"elements" are roughly equally spaced—star at SF end is 8th-mag; next is 8.5-mag, then galaxy, then at NP end of line is an 8th-mag star; all four elements in line spaced 8-10' from the next; whole line about 30'—seeing poor down here—passed over galaxy at least once
NGC 1421 (Eri)—very impressive!—just S of "Zaurak bend"—elongated N-S—3.0' x 0.67'—fairly well defined, particularly on N end—N end a little wider than S end—not a lot of central brightening to galaxy—diffuse but well defined—2/3 of the way from S to N is a dark obscuration across galaxy's width—3' off S end F is a threshold star—P galaxy and a bit N by 3' is a 13th-mag star—N very slightly P galaxy's center by 7' is a 14th-mag star—S and SF the galaxy is an irregular grouping of 9th-12th-mag stars that takes up a big chunk of S and SF edges of field—NP galaxy by 20' is a diamond of stars whose major axis runs SP-NF and is composed of 10th/12th-mag stars; major axis 7' long
NGC 1762 (Ori)—tiny elliptical-ish—maybe 0.5' round—not overly dim, but quite small—has a brighter core region and substellar nucleus—pretty well-defined galaxy amid a rich field—ADS 3623 P galaxy by 23'—ADS 3623 is yellow-white primary, bluish secondary; primary 7th-mag, secondary 9.5; primary SP the secondary; separated by 0.3'—brightest star in galaxy's field is closest vertex of a triangle NP galaxy; brightest star (10th-mag) is 8.5' NP galaxy, and is F-most vertex of triangle; bottom of triangle runs P-F and is 6' long; P-most vertex is 11th-mag; third vertex is N of other two, NP brightest by 4' and is 13th-mag
NGC 1832 (Lep)—much brighter than 1762, not bad—smallish, 1.0' round—diffuse halo, brighter core, no visible nucleus—just outside halo on F side is a 12.5-mag star—N slightly F galaxy's nucleus by 5' is an 10.5-mag star; NF that star by 3.5' is a 12th-mag star—galaxy forms NF vertex of a triangle with an 11th-mag star P and very slightly S by 11'; S very slightly P by 12' is an 11.5-mag star—F galaxy by 18' is a double star; very unequal components; separated P very slightly S-F very slightly N; brighter component F; separated by 0.4'; 11th and 13th-mags—double star N very slightly P galaxy by 8'; aligned P very slightly S-F very slightly N; F star is brighter; 13th- and 14th- mags, separated by 0.5'—seeing really mushy now
NGC 2283 (CMa)—a lot of nothing—quite difficult—extremely diffuse, no central brightening—inside a close triangle of 14th/15th-mag stars, two to N, one to S—hard to gauge galaxy's dimensions, 1.5' round?— two "brighter" vertices of triangle are on N side of galaxy; 14th/14.5-mags, with 14th-mag star NP galaxy, 14.5-mag to NF; third vertex on S edge of galaxy—P galaxy by 10' is an 8th-mag star
NGC 2339 (Gem)—faint but obvious—1.75' round—some slight irregularly-bright central concentration, very faint nucleus or threshold star slightly to NF center of glow—not well defined—galaxy bracketed to P and N slightly F sides by 12th-mag stars; star to P is slightly brighter than other; star to NF about 3' from galaxy's center; star to P is 3.5' from center of galaxy; halfway between galaxy and star to P is a 14.5-mag star—15th-mag star 2.5' S slightly F galaxy—13th-mag star F and slightly S galaxy by 4.5'—brightest star in field is one of a trio along N and NF edges of field; N slightly F galaxy by 19' is a pair of 9th-mag stars separated by 3.5'; one is P slightly N the other; F and slightly N of galaxy by 20' is an 8.5-mag star
NGC 2525 (Pup)—Zager & Evans joke here—interesting galaxy—large, very diffuse glow—elongated P-F-ish—not much central concentration—2.5' x 2.0'—whole lot of faint stars scattered around it—off P edge is a 13.5-mag star; that star has a threshold-level star 0.25' due P—on S edge of the galaxy is a pair or trio of threshold-level stars about 1' from galaxy's halo; F and slightly S that group is another 15th-mag star—just on N edge of halo is a 14.5-mag star; another 14.5-mag star just beyond halo by 1' on F side of galaxy—galaxy between a squiggle of 4 stars to S and a 9.5-mag star N of galaxy; brightest in squiggle (11th-mag) is on NP end, 5' from center of galaxy; second-brightest star in squiggle on SF end—star to N of galaxy 6' from galaxy's edge; leading from N edge of galaxy up to SP side of that star is an arc of five 14.5/15th-mag stars
NGC 2613 (Pyx)—interesting galaxy—large edge-on spiral—elongated P slightly N-F slightly S—3.25' x 0.75'—irregular central brightening along length, very mottled—well-defined galaxy—a number of faint stars N and S of it—brightest of these is a 13.5-mag star P galaxy by 2.5' from galaxy's center—14th-mag star due N of galaxy's center by 1.5'—brightest in field are NP galaxy; one (10.5-mag) is NP galaxy by 8'; other (10th-mag) is NP that star by 5'; NF galaxy by 9' is an 11.5-mag star
Edited by KidOrion, 17 February 2018 - 02:41 PM.