No one else was at Oak Park and there were no cars passing the whole night; I'm sure I was alone for many dozens of square miles. I arrived with plenty of light left to set-up and eat dinner. The air was clear enough so that terrestrial views were clear and sharp, but I knew from satellite images there was a lot of water vapor in the upper atmoshere, making the sky a milky light blue. Seeing was poor at the start of the night but improved later on. Still and all, in spite of the conditions, I was bowled over by what I was able to see. Really quite amazing, and showing to me that even imperfect sky conditions (and observing sites) are still ok for this night vision observing. I used my 4-/8-inch combo refractor with the PVS-14 with the 67mm plossl+ throughout, giving a magnification of 9x with the 4-inch and 18x with the 8-inch. There were a few objects I could have tried higher magnification, but I didn't bother. I also used an ED60 I picked up to try for very wide fields, with a magnification of around 5x. These scopes gave me a range of 2-, 4-, and 9- degrees to view various targets. I continued my run through the Sharpless catalog and added a few extra objects for variety. I observed until 2:30am, and without any other distractions got a lot done.
Sh2-92: 19 46 38.7 +28 14 44, 50': Vague, fairly faint, very large beetle shaped structure, with a large mottled and bifucated body running through two brighter stars and with wispy "arms" to the north and even fainter "legs" to the south. Best seen with 8-inch and OIII. Vogel: Distance: 4400 pc, Size: 64.0 pc. Sh 2-92 is ionised by the Wolf-Rayet star WR 127, a binary star with an O9V companion"
Sh2-52: 19 47 46.3 -23 05 15, 2' = PNe Abell 65: Small, fairly faint cloud with diffuse edges, not as bright in the middle, oval shaped NE-SW, several stars noticed inside, with the brightest of these in the middle. It lies just to the east of a nearly square asterism of stars of equal magnitude. Did not see any color, though visually it might appear blue. Vogel: "It is highly unusual for a planetary nebula because it contains an eclipsing binary central star. See Sh 2-313 for another example of such a blue planetary nebula with a binary central star."
Sh2-91, -94, -96: These are the brighter filaments of the supernova remnant SNR 65.2+5.7: I only realized later that these were all part of the same very large object, and didn't have the presence of mind to try to connect all these wisps together by panning the telescope. Maybe next time:
Sh2-94: 19 27 50.8 +31 28 14, 25': Long, thin strand of nebula with some loose threads lifting off it, especially one to the NE from the middle part of long strand. Some very faint wisps noticed to the east, inside the curve of this strand. Best with 8-inch & dual band Ha+OIII, and noticed after matching the star pattern (elongated triangle of stars pointed NE) with the photo.
Sh2-96: 19 28 42.0 +32 41 21, 25': Very faint, but obvious large wishbone shaped nebula, brightest where the two "bones" join. Seen with 4-inch, brighter in 8-inch, Ha+OIII dual band.
Sh2-95: 19 55 00.9 +29 17 49, 1'. = NGC 6842. Faint star with a very small round glow around it, seen with no filter, verified position from Vogel's finder charts. Too little magnification used to see any more detail.
Sh2-97: 19 56 04.6 +30 15 57, 10': Fairly small, fairly faint, nearly round with a fairly well-defined edge, mottled inside. Detail best with 8-inch and Ha, but with 4-inch I notice nebula trailing off the eastern rim of the nebula then diffusing into a very large cloud to the north and south; this may or may not be part of this planetary nebula. Vogel: "Distance: 3900 pc, Size: 11.3 pc. Sh 2-97 is ionised by at least four stars - two B1V, one B0.5V and one with a spectral type between O9V and B0V."
Sh2-98: 19 58 44.3 +31 25 18, 15': Extremely faint, seen as a contrast change vs. the rest of the sky, fairly large, thick "C" shape almost joined in a circle and seems centered on one of the very faint stars inside. 8-inch and Ha+OIII dual band. Vogel: "Distance: 3600 pc, Size: 15.7 pc. This is a ring nebula associated with a 3000 solar mass molecular cloud and the Wolf-Rayet star WR 130."
Sh2-101: 19 59 56.8 +35 17 27, 20': = Tulip Nebula. Very dramatic nebula. Surrounding two stars, the nebula is bright, pretty large, flower shaped, and fractured by two prominent dark lanes making a "V" shape. The southern edge is very bright, and the rest of the nebula is heavily mottled, diffusing slowly to the NE, far beyond the 20' size in the catalog. With the 4-inch I can see a very large river of nebula flowing SE to NW to the east of -101. Vogel: "Distance: 2683 pc, Size: 2.7 pc, The exciting star for the Tulip nebula is believed to be the O6.5III star HD 227018, which Humphreys places in the Cygnus OB3 association."
Sh2-102: 20 31 46.6 +30 36 19, 40': Long, rather thick, like a broken up contrail, seen with Ha and OIII, best with dual band Ha+OIII in the 4-inch. It stretches nearly the full 4-degree field, and I can fit the Western Veil at the edge of the FOV for an interesting contrast (-102 is much larger and fainter). Runs nearly E-W with a narrower, pointed end to the east and a wider, more diffuse end overlapping with the bright star 41 Cygni, and a very faint, thicker middle bulging to the south.
Sh2-103: Veil nebula. What didn't I see? I used these as finders and saw every designation no problem. In fact all the un-designated wisps were visible, most dramatically the waterfall of nebula to the east of Flemming's triangle, which flowed into the far southern part before hooking to the west. The 8-inch fit about half the total structure and the 4-inch was nearly complete. After noticing I was catching all the fainter designations easily I stopped taking notes and just enjoyed the view for a while.
Sh2-104: 20 17 44.6 +36 44 40, 7': Seen only with the 8-inch with Ha, relatively small, irregularly round shell with slightly fuzzy edges, slightly brighter along the southern rim, centered over a cluster of stars with one brighter star in the middle. It appears connected with a large, faint cloud running NE-SW to the east. Vogel: Distance: 4400 pc, Size: 9.0 pc. About 450 solar masses of gas form a shell around the ionising O6V star in this HII region located in the outer galaxy."
At this point I took a break from the combination scope and attached the PVS-14 to a 60mm ED scope. Commonly used for astrophotography, the scope gave me a 9-degree TFOV. Using a Ha 7nm filter, I tried it on various nebula:
Siv 2: 00:14:36 +50:45:00, 5.5x3-degrees. I wanted to try this very difficult nebula again with a wider field instrument than my NP-101. I found M31 the star hopped over 1 field to a widely spread group of stars surrounding where the nebula is centered. I saw a very vague contrast change from the star background, exceptionally faint, mostly round, with a ragged edge away from M31. It was the right size for the nebula, so I believe I saw it, but only knowing there should be something there.
NGC 1499 & Siv 4: 03:52:24 +32:36:00 9x7 degrees. Siv 4 is the large, very faint nebulous cloud between the Californa Nebula and the Pleidies. I found the California Nebula first. I've seen this object many times before, but holy cow, I'd never seen it so bright and huge. The main body of the nebula, which everyone refers to as NGC 1499, was heavily mottled and with bright streaks, much subtle detail. What surprised me was the faint filimants trailing from it and hooking south were quite obvious and took up half the field. These transitioned to the larger, fainter general glow which extended beyond the FOV and is Siv 4.
Siv 3: 04:57:30 +65:29:00 7.5x4-degrees. Extremely faint, seen as a contrast change with the background sky, bean shaped, fills most of the field.
Sh2-106: 20 27 26.9 +37 23 49, 3': With 8-inch and dual band, small, bright, comma-shaped nebulosity around a star. Seen unfiltered as a hazy elongated glow. Vogel: Distance: 600 pc, Size: 0.5 pc. Despite its appearance, this is not a planetary nebula, but a giant molecular cloud and star formation region ionised by an O8 star, S106IR."
Sh2-107: 20 42 46.4 +36 20 34, 5': Very subtle small faint nebula fanning out to the south from a relatively bright star. 8-inch and Ha. Vogel: "Distance: 2800 pc, Size: 4.1 pc. The bright star in the foreground of this very faint nebula is the B0.5Ib class star HD 197460."
Sh2-108 &-109: 20 22 34.8 +40 15 15, 180': Butterfuly nebula. Large and full of detail. -109 is a channel of large nebula further away from Gamma Cygni, not pictured in Vogel's guide.
Sh2-110: 21 20 48.5 +32 27 28, 50': Large, fairly faint stream of layered and mottled nebulosity, flowing NE-SW between and through two bright stars toward a third farther away. 4-inch and dual band. 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."
Sh2-111: 21 41 52.7 +30 06 20, 90': Very large, very faint, layered cloud of nebulosity between two brighter wisps. Vogel: "The appearance and direction of this object suggests a nearby dust cloud but there seems to be no significant references to Sh 2-111 in the scientific literature."
Sh2-112: 20 33 50.2 +45 39 35, 15': Spectacular. It's on the other side of Deneb from the North America Nebula and therefore is neglected? Bright central region with prominent dark nebula running through it, the nebula is very bright next to the dark nebula suggesting bow shock accumulation. The rest of the nebula is a complex, mottled fan which fades very slowly into the background and is much larger than the 15' listed in the catalog. The whole rest of the field is filled with faint nebulosity. 8-inch and Ha. Vogel: "Distance: 1740 pc, Size: 7.6 pc. The exciting star for this nebula is the O8V class star BD+45 3216 (SAO 49801). The average distance of the stars associated with this nebula is 1740 pc."
Just after this observation, at 11:43pm, a very bright meteorite flashed just west of Cetus' tail, lighting up the ground around me. It flashed brighter in the middle so when it faded it looked like a double tipped spear. There was even rainbow colors in the bright part. The glow held for a second or two before fading. There were a couple other times when a similarly bright meteor must have lit up the sky, but I was looking away from it. Once I was observing and I felt a bright white flash behind me; I turned to look thinking someone had crept up on me and shone a flashlight.
Sh 2-113: 21 20 48.2 +38 05 29, 15': Large looping nebula, looks like a ring of thin faint arms pinched at the southern and northern ends, brighter & thicker near a group of bright stars to the west. Sh2-114 (9') forms the northern apex of the ring, very subtly "X" shaped and seen with the 8-inch only, Ha. Vogel: "Sh 2-113 and Sh 2-114 form, respectively, the southern and northern portions of a filamentary circle that resembles a supernova remnant. However, no supernova remnant appears to be recorded for this location."
Sh2-117: North America Nebula. Like the Veil, what didn't I see? I spent a while looking at the west coast of "Mexico" and noticed the bright edge nibbled by dark nebula, which in astrophotos show pillar structure. All the intervening drapes of faint nebula between the main actors appeared clearly. Something too hard to describe and almost better to just experience.
Sh2-118: 21 37 00.7 +40 12 57, 480': In the 4-inch and Ha, very faint nebulous "atmosphere" in the general area. There is a brighter, smaller long oval island of nebulosity near a distintive triple star / triangle and slanted NE-SW. Vogel: Sh 2-118 is one of the largest nebulae in apparent size in the Sharpless catalog, but essentially nothing about it has been published in the scientific literature. 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."
CTB 1: Supernova remnant. = Abell 85. When I observed this a couple years ago, using my 10-inch f/3.7 with OIII and then unfiltered, I saw the brightest arc along the south/southwestern edge of the SNR as an extremely faint wisp with ragged ends. I tried it again tonight with 8-inch and with the PVS-14 and Ha. It did not jump out right away, but with several minutes' observing emerged from the darkness, and I could see more detail the longer I looked. I saw a large (almost 1-degree), very faint but obvious and moderately thick cloudy arc stretching from the south around to the west and to the north, nearly completing a ring before becoming too diffuse to fully join. This arc is punctuated by three relatively bright stars at nearly equidistant points around it. The middle was filled with extremely faint gauzy nebulosity, which was more a contrast change with the larger sky background, and which partly flowed beyond where the ring would be if it had completed the circle. This is the breakout area one sees in astrophotos, of which there are many, so I share one by "Moorefield" which was posted on S&T's website. (South is up)
Sh2-175: 00 27 18.6 +64 42 13, 2': 8-inch Ha, a small, irregularly round, fairly bright nebula, with a distinctive arc of three varying brightness stars running through it, a bright central star and two fainter on either end. The edges are diffuse but the northeastern edge is comparitively bright, and the southwestern edge is diffuse and fans out from the main round shape. Vogel: "Distance: 1700 pc, Size: 1.0 pc, This is in Cas OB5"
At this point, with the winter constellations higher in the sky, I put the PVS-14 back into the 60ED. I didn't take detailed notes or sketches, but my impressions:
M42: Super wide view. Layers of bright and dark nebulosity giving a three dimensional view, can tell easily the trapezium is lighting up a cloud from within.
The Flame Nebula, the dark nebula looks like a complex tree prominence, rather than blunt tank tracks.
Barnard's Loop: I can trace the entire length, and notice variations in brightness in different sections, and can also see the faint fork near the Meissa nebula
Meissa Nebula (Sh2-264), very large, not fitting in the field, can see the bright rim along the front, and then the tapering tails in the back.
Rosette Nebula: Pillars of dark nebula. Followed the haze from Rosette back toward Barnard's Loop, and did see sections of the drapery of nebula which I notice in Finkbeiner's Ha Map.
Sh2-150: 22 31 11.1 +65 06 51, 40': 4-inch and Ha, very large, broken up circular shape of differeing thickness and brightness, mostly fairly faint but a brigher N-S dagger of nebula in the NE quadrant. Vogel: "Distance: 900 pc, Size: 10.5 pc. Sh 2-150 appears to be part of the Cepheus bubble, the expanding ring of gas and dust surrounding the star cluster NGC 7160 and the Cep OB2 association. The much brighter nebula Sh 2-131 is part of the same structure. Avedisova identifies two B-class ionising stars, HD 213087 and HD 213405."
Sh2-151: 23 03 03.0 +57 04 18, 20': With Ha, faint in the 4-inch but brighter with 8-inch, a wedge shaped wing of nebula near two bright stars, with a brighter edge to the east and the west diffusing slowly into the background. Vogel: "The only thorough paper that analyses Sh 2-151 adopts a kinematic distance of 5800 pc. Five molecular clouds are part of the Sh 2-151 complex and have a total of 29 thousand solar masses. About 700 solar masses has been ionised by an unseen star that is likely obscured by dust in one of the molecular clouds."
Sh2-154: 22 51 24.6 +61 10 50, 60': Seen both 4-inch and 8-inch, Ha, appears as a bright layered & mottled cloud, pretty large and elongated E-W, with many stars involved. Vogel: "Distance: 1000 pc, Size: 17.5 pc."
Sh2-155: Cave Nebula, 22 56 43.2 +62 37 04, 60': Dramatic view! The first thing I noiced was the dark nebula transecting the bright nebula, and the bright nebula rim boardaring the dark nebula, suggesting a bow shock structure. From there the bright nebula fanned out with complex streamers and cloudlets, mixed with many stars, and fading slowly into the rest of the sky. 4-inch for perspective, 8-inch for detail, Ha. Vogel: "Distance: 730 pc, Size: 12.7 pc, The Cave Nebula interacts with the Cepheus B molecular cloud."
Sh2-156: IC 1470, 23 05 09.6 +60 15 23, 2': Very small glow, seen with 8-inch and only when changing filters and noticing the non-stellar round glow vs. the other stars. Confirmed by referring to a finder chart. It is at the tip of the hook of a coathanger asterism. Vogel: "Distance: 4891 pc, Size: 5.1 pc, this HII region is part of the star cluster NGC 7510. It appears to be ionised by a single O7 class star. The bright core is only one of five distinct and apparently independent emission sources within a giant molecular cloud. The distance is estimated to be about 3500 to 4000 parsecs."
Sh2-157, -158, -159: 23 16 03.2 +60 02 44, 90': WOW! Beautiful! Very large lobster claw shaped nebula, with a cluster of stars at the wrist surrounded by a large turbulent cloud, from which two prominant and bright clouds eminate to the north, joining on the other side of the FOV. Each of these "fingers" have nebula clouds beyond them like thick parenthesis. Further to the north are three bright irregular clouds, two of which are Sh2-158 & -159, which fit in my 4-inch field (and which Vogel identifies as NGC 7538, "a major star formation region in Cas OB2. It is surrounded by the much larger diffuse nebula Sh2-161B"). All features are bright and amazing to see, as good as any nebula in the sky. Vogel: "Distance: 2500 pc, Size: 65.5 pc, This is a ring nebula around WR 157, in the Basel 3 (Markarian 50) cluster that is in turn part of Cas OB2."
Sh2-160: 23 05 47.2 +64 40 24, 80': 4-inch and Ha, Very large, long nebula, appears as a thick mottled ribbon twisted in the middle. Vogel: "Distance: 900 pc, Size: 20.9 pc. The HII region Sh 2-160 is located near or within the Cep OB3 association, which is part of the relatively nearby Cepheus molecular clouds, as can be seen on this face-on map. Sharpless lists three possible ionising stars including the B0 III giant HD 218323, which Humphreys assigns to Cep OB3."
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