Sunday, November 27, 2022

pinnacles thanksgiving night

It's been a poor season for observing, with hazy skies and bad seeing.  This new moon week had only one opening, Thanksgiving Day.  Usually I'd be home enjoying the holiday with family, but various scheduling conflicts meant we'd celebrate on Friday.  The GOES satellite still showed gauzy white upper-level water vapor, but with night vision I thought the trip would still be worth it.  I went to Pinnacles because it was slightly closer.  I arrived past dusk and set-up my 4-/8-inch combo refractor quickly, and ate dinner.  There was one family there trying out their telescope, but they left around 7:30pm.  Otherwise I had the place to myself.  It did not get very cold, and there was no dew.  Transparency was definitely off, my SQML did not get above 21.00.  Had the night been better the fainter nebula would have been brighter, and the more difficult less so, it was still a worthwhile night. 

I continued my journey through the Sharpless Catalog using the PVS-14, 67mm Plossl+, and various filters.  I tried out some different eyepiece combinations and found the 67mm is still ideal.  The 11mm Delite starved the PVS of light and the view too grainy, and spread the nebula out too thinly.  The 95mm gave a slightly brighter image but has a narrower field of view, and too much of its inner barrel can be seen.  The 40mm Plossl was ok, a little more image scale, but I could see more detail with the 67mm on the Horsehead than I could with the 40mm because the nebula was not too spread out.

I observed until 1:30 am and made more than 50 observations.

Sh2-93: 19 55 00.6, +27 12 48, 1': Very small, non-stellar haze, seen with the 8-inch unfiltered and only by confirming the star pattern in the field to the DSS image.  Vogel: "Ionised by the O9V star [F89b] S93 1 and appears to contain the infrared star cluster [BDS2003] 16."

Sh2-110:  21 20 48.5 +32 27 28, 50': Considerably faint region of mixed bright and dark nebula centered around two bright stars, generally humped shaped with a bright stream along the northern edge and another along the southern.  Reminicent to the Californa Nebula, but much smaller.  4-inch, good in Ha but surprisingly better with OIII.  Vogel: "This is in the same direction as the high latitude HI shell Hu 8, which consists of about 1300 solar masses of gas, is about 900 thousand years old and lies at a distance of between 350-440 pc."

Sh2-119: 21 18 25.0 +43 56 16, 160': Large oval-shaped, Rosette-like cloud appears to be centered on a bright star.  The complex nebula has many dark crenillations and combed streaks.  There is a large, thick, and bright curved stream to the east with a fainter parenthesis to the west.  Vogel: "Distance: 700 pc, Size: 32.6 pc, This nebula is near the North American nebula (Sh 2-117, NGC 7000) and appears to be ionised by the O 7.5 III runaway star 68 Cygni (HD 203064), which was likely blasted out of the Cepheus OB2 association about 5.2 million years ago."

Sh2-120: 21 03 46.6 +49 52 51, 1': Very difficult, marginal, slightly non-stellar small glow where the object should be on the DSS image, 8-inch unfiltered.  Not really sure I have it.  Vogel: "Distance: 6300 pc, Size: 1.8 pc"  Galaxy Map: "A radio map of Sh 2-120 shows a shell-like structure around a central source. Very little information is available in the literature apart from this map.  According to a 1978 study, Sh 2-120, Sh 2-121, Sh 2-127 and Sh 2-128 are all at about the same distance of 7500 parsecs and are 'probably distant HII regions associated with a spiral feature more distant than the Perseus arm'.  Sh 2-120 appears behind the much closer dark nebula LDN 988, which has been informally called the Pincushion cloud."

Sh2-121: 21 05 12.4 +49 38 59, 1': Difficult, 8-inch Ha only, appears as a "C", with three stars in the open part of the "C".  Overall a small, round, broken up glow.  According to Galaxy Map, "The HII region Sh 2-121 is surrounded by an expanding shell containing about 39 solar masses of gas.  The shell is at least 650 thousand year old and is likely driven by stellar winds from an O8.5 class star.  A 2003 paper reduces the distance to Sh 2-121 to 4500 ± 1000 parsecs, which could make it part of the Perseus arm."

Sh2-122: 23 08 46.7 +14 55 30, 40': Large, very faint, loose and mottled cloud with many broken streams flowing in a disorganized way toward the bright star Markab on the edge of the FOV.  4-inch and Ha.  Vogel: "Distance: 3300 pc. Sh 2-122 is likely a reflection nebula illuminated by an embedded but unseen star and associated with the molecular cloud MBM 55, at a distance of 150 pc."

Sh2-123: 21 42 22.5 +44 32 25, 13': Not small, faint octopus-like cloud, with a looping oval head pointed north and two "legs" uncurling from the brighter southern edge of the loop to the east and west. Vogel: "Distance: 3800 pc, Size:14.4 pc.  Sh 2-113, Sh 2-114, Sh 2-118 and Sh 2-123 appear to be the brightest parts of a large hydrogen-alpha ridge that runs below the Cygnus complex."  Galaxy Map: "Examining this region in hydrogen-alpha suggests that Sh 2-123 is joined to the equally mysterious Sh 2-113, Sh 2-114 and Sh 2-118 in a long ridge of nebulosity south and south-east of Sh 2-117, the North American nebula. Sh 2-114, Sh 2-118 and Sh 2-123 have distance estimates of about 4000 parsecs. If this ridge is also at 4000 parsecs, it must be enormous."

Sh2-124: 21 38 20.9 +50 21 05, 70':  Bright round center to a very large cloud, 2 wings of which spread NE & SW.  The bright center is broken in several pieces, most prominently by a seagull shaped dark nebula E-W, and other sections like cotton puffs.  8-inch for detail but best with 4-inch for perspective, Ha.  Vogel: "Although very little appears in the scientific literature on the mysterious HII region Sh 2-124, located some distance to the west of the Cep OB1 association, recent detailed hydrogen-alpha imaging done for the IPHAS project reveals the structure of this violin-shaped nebula in spectacular detail. Chini and Wink identify two uncatalogued ionising stars, with classes O7V and B2V, and give a distance estimate of 3600 parsecs. Crampton, Georgelin and Georgelin give a kinematic distance (based on gas velocity) of 4400 parsecs. Felli and Harten give a list of 5 ionising stars, including the O7.5 class LS III +50 28, and support the BFS distance estimate of 2600 parsecs"

Sh2-125: 21 53 32.7 +47 16 18, 9': The Cocoon Nebula.  With 4-inch Ha it appears as a uniform round haze with irregular edges.  With the 8-inch there are dark lanes nibblling into the bright nebula, stars scattered throughout, and large faint streaks of nebula framing it to the east.  The dual band Ha+OIII reveals even more nebula to the west.  Interestinly, the star field and dark nebula are less prominent with NV+642 longpass, it remember it looked better visually without NV in a 6-inch f/5 refractor with a 31mm Nagler.  APOD 2009 March 5: "...15 light-years wide, located some 4,000 light years away toward the northern constellation Cygnus. Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by young, hot stars and blue, dust-reflected starlight at the edge of an otherwise invisible molecular cloud. In fact, the bright star near the center of this nebula is likely only a few hundred thousand years old, powering the nebular glow as it clears out a cavity in the molecular cloud's star forming dust and gas."

Sh2-126: 22 34 38 +40 40 00, 160': Very large river of faint nebulosity flowing out of the E & W edges of the field.  It appears as sheets and brighter and fainter nebula, almost combed.  The nebula proper is a bright wedge shape pointed south, with a long tail to the north then curving and diffusing to the east, all comingled with several bright stars.  4-inch and dual band.  Galaxy Map: "This relatively close HII region is also called the 10 Lacertae complex after its ionising star, the O9 V multiple star 10 Lacertae, which forms the core of the Lac OB1 association. The nebula also contains the young Orion type variable emission star LkHA 233."

Sh2-127: 21 28 41.0 +54 37 14, 2':  8-inch, Ha only.  Very small curved glow off the end of a lazy "L" shaped asterism, among two close stars.  Galaxy Map: "Radio analysis reveals that Sh 2-127 consists of two distinct components - a larger weaker and more diffuse source (WB89 85A) to the northeast, consistent with ionisation by an O7 class star, and a stronger but smaller source to the southwest (WB89 85B), consistent with ionisation by an O8.5 class star. (However, it is also possible that both components are ionised by a single star.) Both components are located near the northwestern edge of a molecular cloud and are embedded in the molecular gas.  According to a 1978 study, Sh 2-120, Sh 2-121, Sh 2-127 and Sh 2-128 are all at about the same distance of 7500 parsecs and are "probably distant HII regions associated with a spiral feature more distant than the Perseus arm"."

Sh2-136: = "Gespensternebel" = "Ghost Nebula".  21 16 29.5 +68 15 12, 5': 8-inch unfiltered.  Very small and very faint glow around a star (found by carefully studying the chart and finding the "L" shaped asterism), with long study I could detect extremely faint and small extensions to the east & west.   The DSS image is brigher and larger image scale than what I saw.  Vogel: "Distance: 450 pc, Size: 0.7 pc.  This is a Bok globule, not an HII region. Inside the glowing globule, CB 230, new stars are being born. Within the Lynds dark nebula LDN 1177."

Sh2-139: 22 34 59.4 +58 13 02, 10': Fairly large mottled cloud within a triangle of stars.  There's a brighter patch of nebula on the southern corner of the triangle.   Distance: 3300 pc, Size: 24.0 pc.

Sh2-161: 23 15 29.2 +61 51 43, 55': 4-inch Ha, very large glow with many stars intermingled, looks like a puffy cumulus cloud with a stream sprouting from it to the south which then curves east to the edge of the bright knot Sh2-158, which then combs back to the west, forming a very large, thick & diffuse ring.  Vogel: "Distance: 2800 pc, Size: 44.8 pc., Sh 2-161B is a large diffuse nebula surrounding the much smaller (and better studied) Sh 2-158, which is visible in the bottom right of this image."  

Sh2-162: = NGC7635, Bubble Nebula.  23 20 41.5 +61 11 52, 40': 4- & 8-inch Ha.  The complex nebular region is highlighted by a very bright & thin ring, brightest near a double star and thinnest over what appears to be a dark nebula.  There is a second, larger and fainter ring which has it's origin also near the double star but is about twice the diameter of the first and intersects two bright stars.  There are curtains of nebulosity draping to the south and the whole complex connects with other nebula in & beyond the field.  Vogel: "Distance: 3813 pc, Size: 5.8 pc.  This is the Bubble nebula, NGC 7635, a circular shell around the O6.5 IIIf star BD +60°2522."  APOD 2009 October 30: "Embedded in a complex of interstellar dust and gas and blown by the winds from a single, massive O-type star, the Bubble Nebula (aka NGC 7635) is a mere 10 light-years wide....distance estimates for the Bubble Nebula and associated cloud complex are around 11,000 light-years"

Sh2-163: 23 33 19.3 +60 47 09, 10': 8-inch and Ha, moderately large curving nebula, NE-SW, with a brightly defined NW edge and faint & diffuse nebula draped from it, broken up by dark nebula.  There is a large faint sheet of nebula drifting off to the NE out of the field.  Vogel: "Distance: 3839 pc, Size: 12.4 pc, Ionised by the O 9.5 V class star LSI +60 8 at 2800 parsecs and contains the infrared cluster [BDS2003] 45. A second distance estimate of 2500 parsecs."

Sh2-164: 23 38 25.3 +59 58 13, 3': 8-inch Ha, Very small comma shaped glow, faint, confirmed by identifying the star field in the DSS image.  Vogel: "Distance: 5000 pc, Size: 4.4 pc, Ionised by the B1 Ib supergiant LS I +59 10 with two distance estimates of 3500 +/- 1500 parsecs and 2820 parsecs." Galaxy Map: "Russeil combines Sh 2-163, Sh-164 and Sh 2-166 into a single star formation region."

Sh2-165: 23 39 48.1 +61 56 15, 10': Easily seen with 4-inch, much detail seen with 8-inch, Ha.  Fairly large, roundish mottled cloud with subtle variations in brightness, which resolves with very careful viewing to a very subtle, thin oval band running through the more diffuse nebula E-W.  Ring structure?  Diffuse edges, fades slowly, Sh2-166 on the edge of the FOV.  Vogel: "Distance: 1600 pc, Size: 4.7 pc, Excited by B0 V star BD 61 +2494, distance estimates of 2020 and 2400 parsecs. Contains the infrared cluster [BDS2003] 46"  

Sh2-166: 23 42 09.8 +60 58 17, 10': Easy with the 4-inch, viewed for detail with 8-inch, Ha.  Pretty bright round glow with soft edges, very subtly mottled within.  There is one brighter star offset to the north, making the nebula look like the coma of a comet.  More bulk to the nebula on the northern half.  Vogel: "Distance: 2400 pc, Size: 7.0 pc, This faint nebula forms part of the Cas Ob5 supershell."  Galaxy Map: "Avedisova places it in the star formation region SFR 114.63-0.79 along with a water maser, the radio source KR 82 and the young stellar object Mol 160....A recent Spitzer study concluded that Mol 160 is 3000 times more luminous than the sun, is accreting matter from a 220 solar mass dust cocoon and has not yet undergone hydrogen fusion."

Sh2-167: 23 35 21.8 +64 51 11, 2': 8-inch only, 642 longpass.  Very small, difficult, appears as a sunny-side-up egg, a star with a uniform round glow around it, soft edges.  Identified by following the star patterns in the DSS image.  Galaxy Map: "There is very little information in the scientific literature on this faint nebula.  Sh 2-167 was previously listed as a planetary nebula but is now believed to be an HII region. It appears in the direction of a large expanding shell around Cas OB5, but the available distance estimates suggest that it may lie much further away in the Outer/Norma arm."  

Sh2-168 & -169.  
-168: 23 53 03.5 +60 28 23 7' 
-169: 23 53 58.0 +60 22 23, 5':  4-inch & 8-inch, Ha & dual band.  
-168 is pretty bright round small, with a very bright central region and a bright round rim to the SE, and diffuse edges elsewhere.  Galaxy Map: "Avedisova concludes that the HII region Sh 2-168 is ionised by the O9 V star LS I +60 50. SIMBAD gives a slightly cooler B0 V spectral class. This is in the direction of an expanding shell surrounding Cas OB5.  Avedisova places Sh 2-168 in the star formation region SFR 115.80-1.60 along with the radio source KR 84. The nebula includes the loose infrared cluster [BDS2003] 47 and the Herbig-Haro object GM 2-44."  
-169 is slightly smaller but very much fainter, with very diffuse edges and a central star.  Galaxy Map: "A faint nebulosity near the direction of the much brighter Sh 2-168. Avedisova finds that it is ionised by the B0 III giant BD +59 2786."

Sh2-170: 00 01 42.0 +64 37 24, 20': 4- & 8-inch, Ha.  Very beautiful, large round glow, bright, mottled throughout with soft edges, with a central triple star.  Vogel: "Distance: 2300 pc, Size: 13.4 pc.  Sh 2-170 is in the vicinity of the Cassiopeia OB5 supershell. The sole exciting star of Sh 2-170 is DM+63 2093, an O8 V star of 31 solar masses."

Sh2-171: = NGC7822 + Ced214.  00 04 40.0 +67 09 24, 180': 4- & 8-inch Ha.  Incredible! Very dramatic riot of curved bright nebula with dark nebula chewing complex patterns and pillars into it, stars scattered throughout.  Impossible to describe.  An ominous smoke of layered nebula to the north stretches far beyond the FOV.  Vogel: "Distance: 840 pc, Size: 44.0 pc.  This expanding shell of gas and dust was created by the original star cluster at the heart of the Cep OB4 association, which has now dispersed. It is now lit and ionized by the young star cluster Berkeley 59, at its south end (Cederblad 214) and it is expanding into the dark nebula NGC 7822 at its north end. Berkeley 59 is surrounded by another dark region of disturbed gas and dust containing the radio source W1." 

Sh2-172: 00 15 32.2 +61 15 21, 1':  Pair of very small, very faint sunny-side up eggs, small, faint.  8-inch unfiltered, identified with aid of the DSS star field.  Galaxy Map: "Sh 2-172 contains the loose infrared cluster [BDS2003] 48.  Russeil combines Sh 2-172, Sh 2-173 and Sh 2-177 into one star formation region and comments that no stellar distance is known for Sh 2-172. All three nebulae lie in the direction of the expanding shell of gas and dust surrounding the Cas OB5 association."

Sh2-173: 00 21 51.8 +61 44 17, 30': 4- & 8-inch Ha.  Rather large, fairly bright nebula, brokenly round and seemingly centered on one of three similar magnitude stars.  It looks like an e-clip, with two dark pillars intruding into the nebula.  The brightest rim of the nebula runs through the northernmost star in the triangle, and looks like a bow shock.  Vogel: "Distance: 2700 pc, Size: 23.6 pc.  Sh 2-173 is part of the Cas OB5 super shell."

Sh2-174: 23 46 49.1 +80 56 20, 10': Extremely faint, moderately sized U-shaped glow, appears only as a contrast change.  Tough!  8-inch and Ha only.  Vogel: "The former central star of this old planetary nebula, the white dwarf GD 561 [the very faint star to the left of a brighter one, which I identify with blue hash marks in the below photo], has drifted to the outside of the nebula. Both are located about 300 pc away."

Sh2-175: 00 27 18.6 +64 42 13, 2': Identified only by referring to the DSS photo.  In the 8-inch with Ha, appears as a small non-stellar glow, larger than equivalent magnitude star bloating seen in the same field.  No detail seen.  Vogel: "Distance: 1700 pc, Size: 1.0 pc.  This is in Cas OB5.

Sh2-176: 00 31 38.3 +57 17 09, 10': Very faint wisps of curving nebulosity, many faint stars scattered within it--reminds me of a very small version of the Eastern Veil.  8-inch Ha.  I saw the southern half of the full ring, I did not see the northern and excessively faint ring.  Vogel: "This is a planetary nebula at a distance of about 140 pc. The central star is a blue subdwarf."

Sh2-177: 00 31 32.4 +62 28 09, 40': 4-inch and Ha.  Large, extremely faint stream of nebulosity, seen as a contrast change and moves with the scope.  It curves gently NE-SW, and has a fainter dorsal-like fin of nebulosity diffusing to the NW.  Vogel: "Distance: 2500 pc, Size: 1.5 pc.  This region of faint nebulosity may be part of the shell surrounding Cas OB5."

Sh2-179: = PNe BV 5-2. 00 40 24.6 +62 51 58, 1':  Very difficult at this image scale!  Very small non-stellar, extremely faint glow, with most of the glow on the north side of a star.  Identified only by comparing to the DSS image.  8-inch and Ha+OIII.  

Sh2-180: 00 48 46.3 +62 55 45, 15': Exceedingly faint, moderately sized, seen as a contrast change, vaguely a broken up oval, with one strip along the SE rim as the brightest part.  8-inch and Ha only.  Vogel: Distance: 6100 pc, Size: 26.6 pc.  Sh 2-180 is visible in the direction of the Perseus arm Cas OB7 association, but a distance estimate based on CO velocity places it much further away in the Outer arm. Avedisova also locates it at a large distance and concludes that it is ionised by the O7.5V star LS I +62 139 at a distance of 5150 +/- 1300 parsecs. The filaments visible in this image, more characteristic of a close supernova remnant than a distant HII region, suggests that this region may deserve deeper investigation." 

Sh2-181 / -183.  -181: 00 49 16.5 +65 12 44 15, 3'.  -183: 00 53 59.1 +65 42 35, 35'.  Sh2-181 is a pretty bright irregular arc of nebulosity orientated N-S, with a brighter & thicker base to the south.  In the same field to the NE is -183, with is large, faint, mostly round but mottled and broken up by dark lanes.  4- & 8-inch, Ha.
-181 Galaxy Map: "Radio observations and modelling suggest that Sh 2-181 is an HII region ionised by a B0 to B0.5 class star. A 1978 paper identifies the ionising star as the B1 V class LS I +64 47. The nebula is connected to the Cas OB7 association in the Perseus arm."  
-183 Galaxy Map: "This is an apparently large and distant HII region that is obscured by foreground dust. It consists of 44 thousand solar masses of ionised gas and is at least 3.9 million years old. The stars ionising the gas are unknown and are probably obscured by the foreground dust....If this object is really located at 7000 parsecs, then the size in the radio image suggests that it may be one of the largest star formation regions in the outer galaxy. Note, however, that streaming motions in the Perseus arm can result in exaggerated distance estimates if velocity data is used alone to determine an object's distance (and the current distance estimate is, indeed, based on gas velocity)."

Sh2-182: 00 50 16.4 +64 44 42, 2': Extremely difficult, marginal observation.  I identified the correct location using the DSS plate, and think I saw an excessively faint and small glow, but it could have been some bloating of the star image by the PVS-14 device.  8-inch unfiltered.

Sh2-184: = NGC 281, Pacman. 00 52 50.1 +56 36 37, 40': Showpiece.  Bright, wedge shaped, with loops and pillars of dark nebula intruding from the west, and a wind blown spray of neblulosity diffusing from the northern tip.  Many bright stars intermingled.  8-inch Ha.  Vogel: "this bright nebula located far below the galactic plane....IC 1590, the star cluster at the heart of the nebula, is about 3.5 million years old. The core of the star cluster IC 1590 is the O6 class trapezium system HD 5005, which ionises Sh 2-184."

Sh2-185: IC 59/63.  00 60 00.0 +60 59 23, 120': Seen easily with 4-inch, appear as seagull wings.  Connects to IC 59 with faint curtain of nebulosity.    

Sh2-186: 01 08 50.7 +63 08 02, 1'. Small and faint glow identified with the DSS plate, 8-inch unfiltered & Ha.

Sh2-187:  01 23 07.0 +61 51 24, 10': Difficult!  Faint nebulosity is mixed with dark nebula to make it nearly impossible to detect.  It appears as an extremely subtle contrast change with the sky.  Brightest parts are very small as compared to the 10' size.  8-inch and Ha only.  Vogel: "Distance: 1000 pc, Size: 2.9 pc.  This young (100-200 thousand years) star formation region is most likely ionised by a B0 star and is surrounded by a 4600 solar mass molecular cloud."

Sh2-188: = Simeis 22. 01 30 38.6 +58 22 01, 9': Easily seen with the 4-inch, used 8-inch for more detail, Ha+OIII.  Streaks of fairly bright nebula all layer to form the fairly bright curving body, with the brightest layer being the southeastern rim.  There are thin faint extensions coming from the western tip, and dense brush-like extensions from the northern tip, making it look like a shrimp.  In the DSS plate these extensions seem to join to form a complete ring but I did not see that.  Vogel: "This is planetary nebula Simeis 22 with a distance of 218 pc and an expansion age of 7500 years."

Sh2-189: = Abell 3, 02 12 07.6 +64 10 18, 2': With 8-inch unfiltered, I a very small, very faint non stellar round glow, difficult, identified by looking at the DSS plates.

Sh2-250: near NGC1633/1634 (galaxies) 04 40 10.8 +07 21 47, 10': There is a very faint sweep of nebula running parallel to two bright stars, N-S, brightest view with the 8-inch Ha.  In the 4-inch I see these sweeps extend further to the NE in much fainter wisps.  I did not notice the two NGC galaxies, which seemed stellar (at least I sketched them as stars in my notebook--they are the two close bright spots just to the north of center in the image, blue hash marks).

Sh2-251: 04 32 49.0 +05 51 46 35': Very weak wisps of cloud orientated N-S toward a triangle of bright stars, seen as a very faint contrast change which moves with the scope.  Galaxy Map: "Sh 2-250 and Sh 2-251 appear to be areas of nebulosity within the Orion-Eridanus superbubble, like Sh 2-245. The superbubble is ionised by ultraviolet radiation from the hot stars of the Ori OB1 association."

Sh2-252: = NGC2174/2175/IC 2159 "Monkey Head", 06 09 38.7 +20 30 01, 40': Very bright nebula, easy in the 4-inch Ha, best for detail in the 8-inch and Ha+OIII.  Many stars within the nebula, which sweeps in many combed layers from the westers wall (dark nebula cutoff) to the west then curves upward.  The interior is heavily mottled with dark and bright wisps.  The nebula evaporates from the northern end into thin streams half the length of the main nenula.  Vogel: "surrounds the NGC 2175 star cluster in the depths of the Gemini giant molecular clouds."

Sh2-253: 06 25 43.0 +20 01 41, 5' With 8-inch Ha, short, weak streak of nebulosity with ragged ends, intermingled with numerous stars.  Vogel: "Distance: 4400 pc, Size: 6.4 pc Sh 2-253 is probably ionised by stars in the Bochum 1 (C 0622+198, more or less centered in the image) star cluster, including the B 1.5 V class LS V +20 40."

Sh 2-254: 06 12 20.5 +18 02 37, 11'
Sh 2-255: 06 13 08.4 +17 58 31, 3'
Sh 2-256: 06 12 38.3 +17 56 35, 1'
Sh 2-257: IC 2162 06 12 50.4 +17 58 33, 3'
Sh 2-258: 06 13 32.3 +17 55 27, 1'
Really interesting!  First impression is of a snowman that's been toppled over.  Bright, nearly uniform round glows, each with a central star, in a row, with -254 the westernmost and largest, then -257 to the east with a slight gap, and -255 further east with a somewhat larger gap.  Each with soft edges.  -256 is a small but bright oval glow, and -258 is detatched from the group, a very small round glow around a faint star (which I would not have noticed if not for the label on the DSS plate).  8-inch Ha.  Vogel: "Distance: 2000 pc, A molecular cloud with 27 thousand solar masses surrounds the Sh 2-254 to Sh 2-258 HII and star formation region."

Sh2-259: 06 11 36.7 +17 26 44, 2': Unfiltered 8-inch, appears as a very small, fairly faint sunnyside-up egg, but with an incomplete circular glow around three stars.  Galaxy Map: "This HII region lies in the direction of the Gem OB1 molecular clouds but its distance seems to make it a background object in the outer Cygnus arm. It is centred around the B1 V star ALS 18669."

Sh2-260: 04 55 07.0 +05 39 43, 22' 4-inch Ha, Large, very vague and extremely faint, roughly triangular contrast change, but I can't detect any detail.  Vogel: "This red filamentary nebulosity is in the general direction of the Taurus dark cloud. It is most likely associated with the Lambda Orionis ring (Sh 2-264)."

Sh2-261: = Lower's Nebula, 06 08 56.6 +15 48 07, 45': 8-inch and Ha+OIII.  Large, bright, round, with a comma-shaped tail to the north.  Brighter section to the south.  Heavily mottled and broken-up nebula, with numerous stars inside.  Beautiful, a showpiece. Vogel: "appears to be ionised by the O7.5V runaway star HD 41997" -- so it may be a temporary illumination of this part of the sky.  Vogel indicates which parts of the nebula are seen best with visual filters, but I saw the whole thing together with PVS-14 and dual band Ha+OIII.

Sh2-262: 05 06 44.7 +06 10 04, 20' Seen with the 4-inch, brighter with the 8-inch Ha.  Fairly large nebula streams diagonally from a long "L" shaped asterism, very faint and scattered cloud.  Vogel: "Distance: 900 pc, Size: 5.2 pc, This nebula is most likely associated with the Lambda Orionis ring (Sh 2-264)."

Sh2-263: 05 21 44.4 +08 23 56, 22': Very soft round glow to the SW of a bright star, with a defined rounded edge / dark cut-off to the northwest and very faint extensions streaming south, with more extremely faint nebula in the general area around the star.  4- & 8-inch with Ha+OIII.  Galaxy Map: "This HII region and reflection nebula is ionised by the B0-B1 V star HD 34989. Avedisova places it in star formation region SFR 195.06-11.99 as part of the Lambda Orionis ring complex along with Sh 2-264, Sh 2-265 and the dark nebula LDN 1582 (Barnard 32)"


Monday, November 21, 2022

15 november 2022 perseus struves

With the 6-inch f/15 refractor again.  Some haze in the hair and imperfect seeing, but still good enough to continue Struves in Perseus.

STF 351 AB: 152; 125x: Near equal white pair, wide.  WDS says not physical, and there is no overlap of the parallax ranges, -90%, is it not binary.
03h 09m 02.75s +44° 15' 06.4" P.A. 115.00 sep 27.1 mag 9.18,9.87 Sp A0

STF 352 AB: 152; 250x: Very closely separated, 2 Dm, B seen with averted vision only.  WDS says physical, and there is 64% overlap of the parallax ranges, only 514 AU weighted separation, 1.9+1.1 Msol, and the radial velocity delta 1.6 is less than the escape velocity 3.2, it is very likely binary and needs an orbit.
03h 08m 45.91s +35° 27' 31.1" sep 3.9 mag 7.80,9.65 Sp A0 dist. 155.52 pc (507.31 l.y.)

STF 360 AB: 152; 125x: Closely separated yellow-white pair, slight magnitude difference, pretty nice.  WDS grade 4 orbit 1500-year period.  But, there is no overlap of the parallax ranges, -9%, so in spite of the close weighted separation of 130 AU and 1.1+1.0 Msol, it probably is not binary.
03h 12m 09.59s +37° 13' 03.3" P.A. 124.70 sep 3.0 mag 8.02,8.29 Sp G0 dist. 39.92 pc (130.22 l.y.)

STF 361 AB: 152; 125x: B is seen just barely with direct vision, brighter with averted vision, well split, with STF360 on the edge of the FOV.  WDS says proper motion indicates physical, and there is 54% overlap of the parallax ranges, 3,931 AU weighted separation, 2.4+1.7 Msol, but the radial velocity delta 1.5 is slightly above the escape velocty 1.4, so needs an orbit to check.
03h 12m 19.25s +36° 59' 47.2" P.A. 15.00 sep 10.6 mag 8.98,11.02 Sp A0

STF 364 AB: 152; 125x: Near equa, well separated pair.  WDS says parallax indicates physical, and there is 33% overlap of the parallax ranges, 1,602 AU weighted separation, 1.5+1.5 Msol, and the radial velocity delta 0.2 is less than the escape velocity 1.8, so it is likely binary and needs an orbit.
03h 13m 35.34s +39° 08' 41.5" P.A. 311.00 sep 11.7 mag 8.73,8.92 Sp F0 dist. 178.89 pc (583.54 l.y.)

STF 369 AB: 152; 125x: Brilliant white stars, fairly close, 1 Dm, nice.  WDS uncertain, and there is no overlap of the parallax ranges, -40%, it is not binary.
03h 17m 11.45s +40° 28' 58.6" P.A. 29.00 sep 3.6 mag 6.83,7.72 Sp B9VpSi dist. 197.63 pc (644.67 l.y.)

STF 370 AB: 152; 125x: Light orange A, 3 Dm B seen with averted vision only, wide.  WDS says not physical, and there is no overlap of the parallax ranges, -95%, not binary.
03h 16m 35.60s +32° 38' 14.4" P.A. 320.00 sep 16.9 mag 8.88,11.00 Sp K0

STF 371 AB: 152; 200x: Pretty difficult in poor seeing, light yellow-orange A and much fainter, 3 Dm B seen averted vision only, very closely split with seeing.  WDS says it is physical, and there is 57% overlap of the parallax ranges, only 631 AU weighted separation, 1.9+1.3 Msol, and the radial velocity delta 1.5 is less than the escape velocity 3.0, so it is likley binary and needs an orbit.
03h 18m 40.61s +47° 01' 31.6" P.A. 89.00 sep 3.2 mag 8.50,10.55 Sp F0 dist. 179.21 pc (584.58 l.y.)

STF 372 AB: 152; 125x: Faint, near equal, wide, in a steream of similar stars.  WDS says proper motion indicates not physical, but there is 46% overlap of the parallax ranges, 2,682 AU weighted separation, 1.7+1.6 Msol, so it might be binary.
03h 19m 18.52s +45° 57' 04.7" P.A. 292.00 sep 7.7 mag 10.19,10.58 Sp A9V dist. 500 pc (1631 l.y.)

STF 382 AB: 152; 200x: Bright white A, tremulous in poor seeing, can see closely separated B with foveal coaxing only.  WDS says it is physical, but there is no overlap of the parallax ranges, -25%, it is not likely binary.
03h 24m 29.68s +33° 32' 09.7" P.A. 153.00 sep 4.7 mag 5.80,9.25 Sp A0V dist. 133.51 pc (435.51 l.y.)

STF 386 AB: 152; 200x: Very closely separated near equal pair, with seeing.  WDS says proper motion indicates physical, and there is 74% overlap of the parallax ranges, only 783 AU weighted separation, 1.9+1.9 Msol, and the radial velocity delta 0.1 is less than the escape velocity 2.9, so it is likely binary and needs an orbit.
03h 28m 02.19s +55° 10' 29.2" P.A. 59.00 sep 2.7 mag 9.46,9.60 Sp A2

STF 388 AB: 152; 125x: Pretty light yellow A and blue B, 1 Dm, closely separated, field has many faint stars wanting to show more. Near Mirfak.  WDS uncertain, but there is 77% overlap of the parallax ranges, only 491 AU weighted separation, 2.1+1.7 Msol, so it is likely binary and needs an orbit.
03h 28m 40.39s +50° 26' 10.8" P.A. 214.00 sep 2.8 mag 8.04,9.01 Sp F0 dist. 130.04 pc (424.19 l.y.)

STF 391 AB: 152; 125x: Stunning ice blue A and pale gold B, closely separated, 1 Dm.  WDS uncertain, and there is -26% overlap of the parallax ranges, surprisingly it is not likely binary.
03h 29m 13.74s +45° 02' 57.5" P.A. 96.00 sep 3.9 mag 7.60,8.32 Sp B2IV dist. 1111.11 pc (3624.44 l.y.)

STF 392 AB: 152; 125x: Light orange A and faint blue B, wide.  WDS says proper motion indicates it is physical, and there is 6% overlap of the parallax ranges, 6,067 AU weighted separation, 3.1+1.4 Msol, but the radial velocity delta 3.9 is greater than the escape velocity 1.1, so it is likely not binary.
03h 30m 17.71s +52° 53' 41.3" P.A. 347.00 sep 25.8 mag 7.45,10.34 Sp K0 dist. 212.31 pc (692.56 l.y.)

STF 410 AB: 152; 125x: Very faint B seen with averted vision only, wide.  WDS uncertain, but there is no overlap of the parallax ranges, -23%, it is not binary
03h 35m 01.16s +32° 01' 00.7" P.A. 213.00 sep 5.1 mag 6.71,10.70 Sp F5V dist. 75.24 pc (245.43 l.y.)

STF 413 AB: 152; 200x: Faint near equal pair, split with seeing only.  WDS uncertain, but there is 64% overlap of the parallax ranges, only 410 AU weighted separation, 1.5+1.5 Msol, and the radial velocity delta 0.1 is less than the escape velocity 3.6, it is likely binary and needs an orbit.
03h 35m 23.04s +33° 40' 33.4" P.A. 126.00 sep 2.4 mag 9.29,9.30 Sp F0 dist. 167.22 pc (545.47 l.y.)

STF 425 AB: 152; 200x: Light yellow stars, significant delta, split with seeing.  WDS grade 4 orbit, 947-year period.  There is 69% overlap of the parallax ranges, only 91 AU weighted separation, 1.2+1.2 Msol, so it is certainly binary.
03h 40m 07.24s +34° 06' 59.3" P.A. 59.30 sep 1.7 mag 7.52,7.60 Sp F9V dist. 46.02 pc (150.12 l.y.)
STF 426 AB: 152; 125x: Wide 1 delta white stars.  WDS says proper motion indicates physical, but there is no overlap of the parallax ranges, -47%, so it is not binary
03h 40m 50.17s +39° 07' 01.7" P.A. 341.00 sep 19.6 mag 8.68,9.39 Sp A7IV dist. 266.67 pc (869.88 l.y.)

STF 431 AB: 152; 125x: Bright yellow-orange A with a wide faint companion, 4 Dm.  WDS uncertain, but there is 78% overlap of the parallax ranges, 7,335 AU weighted separation, 6.0+1.8 Msol.  The secondary is a little far from the primary but there's a lot of mass in the system, so it could be binary and needs an orbit.
03h 42m 22.64s +33° 57' 54.1" P.A. 239.00 sep 19.9 mag 4.97,10.04 Sp B1.5IV dist. 323.62 pc (1055.65 l.y.)