This set of observations includes a review of mostly brighter planetary nebulae. I was hoping to draw out more internal structure in my 17.5-inchI also spent some time wandering around the dusty Rho Ophiuchi region and some of the brighter reflection nebulosities. Sharpless 2-68 is a huge, dim, structureless nebula (475"x330"), that may be an ancient PN or an HII region and the Crescent Nebula, NGC 6888, showed some much structure at 2:00 AM on Friday night from Bumpass that it was difficult to take notes! Additional observations with my old 13" and C-8 (some going back nearly 20 years!) are included.
Steve Gottlieb
17.5" (6/30/00): Stunning view at 100x (20mm Nagler) using an OIII filter. The outline appears as a huge, irregular cosmic egg sitting in a very rich Cygnus star field, ~18'x11', with the complete annulus easily visible. The brightest section is along the north side and passes through a mag 7.2 star at the north edge. This piece is shows a much structure with several knots and wispy tendrils. An isolated bright knot is within the weakly glowing interior which has an irregular surface brightness and is on a line with the mag 7.2 star and the mag 7.4 central star. There are interior wispy striations which appear to radiate from the central star towards the NW rim at the end of the bright arc. The rim is widest on the SW end with more nebulosity filling in towards the center. The fine texture and structure of the nebulosity creates a 3-dimensional feel and an "electric" affect.
17.5": the "Crescent Nebula" is one of my favorite large nebulosities at 100x with a OIII filter (excellent contrast gain). Appears as a bright, 16'x11' oval or egg-shaped annulus elongated SW-NE. The rim is virtually complete except for a small piece of the east side and exhibits a great deal of turbulent, wispy structure. Brightest just SW of mag 7.2 SAO 69597 (unequal pair 7.2/10.5 at 14") which is embedded in the rim at the north end. The nebula also passes through mag 8.2 SAO 69611 on the NE side. Just north of center in the interior is mag 7.4 SAO 69592. This is beautiful nebulosity set in a very rich milky way field.
13": bright, large, oval shell, nearly complete loop visible with UHC, striking unusual appearance!
8": faint, elongated arc of nebulosity connecting two mag 7.5/8.5 stars and extending SW of the brighter star. Set in a very rich star field. Only the brightest portion at the north end of the nebula is visible.
NGC 6026 = PK 341+13.1 = E389-PN7
16 01 20.9 -34 32 39
V = 12.9; Size 54"x36"
17.5" (6/30/00): at 220x this fairly faint PN appeared slightly elongated SW-NE, ~50"x35". The 14th magnitude central star is easily visible encased by an evenly lit disc. The edges of the halo appear somewhat ragged but the PN is crisp-edged at 280x using a UHC filter.
13": very faint, small, round. A very faint mag 14 central star is visible. The planetary is visible with direct vision using a UHC filter. Located 7.3' NW of mag 7.6 SAO 207243.
8": not found.
NGC 6072 = PK 342+10.1 = E389-PN15 = Hb 3
16 12 58.1 -36 13 48
V = 11.7; Size 70"
17.5" (6/30/00): at 280x using a UHC filter this southerly PN appeared fairly bright, round, 60" diameter. The surface brightness was uneven with an irregularly brighter rim and a slightly darker center.
13": moderately bright and large, roundish, 1.0' diameter, fairly prominent with a UHC filter at 166x. No structure at 332x although this planetary is far south for viewing from northern California.
8": faint, fairly small, round.
NGC 6302 = PK 349+1.1 = Bug Nebula
17 13 44.6 -37 06 12
V = 9.6; Size 83"x24"
17.5" (6/30/00): at 280x (unfiltered) the Bug Nebula is a remarkable, high surface brightness object, elongated 3:1 WSW-ENE, ~2.0x0.7'. The intensely bright 10" core appears elongated SW-NE and is offset to the east of center. A quasi-stellar nucleus sharpens to a stellar point when the seeing steadies. The western wing is longer and is nearly split at the midpoint by a dark slash oriented N-S with a brighter condensation at the west end. The shorter eastern wing is more pinched and just past its midpoint there is a kink and it angles towards the SE.
13": bright, fairly small, elongated E-W, very high surface brightness. Subtle structure but the western extension is notably longer, brighter and cut by a dark lane. The eastern extension bends slightly south just east of center.
NGC 6309 = PK 9+14.1 = Box Nebula
17 14 04.2 -12 54 39
V = 11.5; Size 52"
17.5" (6/30/00): at 280x using a UHC filter this bright but compact PN was elongated 2:1 in the direction of a mag 12 at the NNW edge, ~25"x12". There is a large, bright lobe or condensation at the north end with a smaller, fainter knot at the SSE end. At moments the lobes appear completely "resolved" with a darker gap in the center. The view at 500x was excellent! The fainter southern lobe appears elongated and slightly offset from the major axis of the PN. The lobes are bisected by a darker lane oriented SW-NE and oblique to the minor axis. The brighter knot at the north end has a mottled appearance and irregular shape.
13": moderately bright, small, elongated NNW-SSE. A mag 12 star is at the NNW edge 20" from the center. Appears slightly brighter or a condensation is at the SSE end.
NGC 6337 = PK 349-1.1 = E333-PN5
17 22 15.6 -38 29 01
V = 12.3; Size 49"x45"
17.5" (6/30/00): very pretty annular PN at 280x, ~45" and set in a rich star field. A mag 12 star is superimposed on the inner edge of the NE rim and an extremely faint star is symmetrically placed at the SW edge. The darker hole is 20"-25" diameter and perfectly circular. The outer rim appears irregularly lit.
13": at 166x with a UHC filter appears fairly faint, fairly small, roundish. Slightly darker center (annular) with averted vision although low contrast with rim. No central star seen.
NGC 6369 = PK 2+5.1 = Little Gem Nebula
17 29 20.1 -23 45 44
V = 11.4; Size 30"
17.5" (6/30/00): at 500x the "Little Gem Nebula" has a beautiful annular appearance with a 25-30" halo perforated by a 12" dark hole. The northern rim is noticeably brighter with a nearly stellar spot near its center.
17.5" (6/5/99): bright, beautiful annular planetary at 380x with a well-defined dark central hole. The rim is clearly brighter along the north edge and slightly weaker on the following edge.
17.5": bright, fairly small, about 30" diameter, green-blue color. Appears as a perfect annular ring at 286x with a 15" central "hole". No central star visible.
13": beautiful ring at 214x and UHC filter, small, slightly elongated. The N edge of the rim appears brighter.
NGC 6563 = PK 358-7.1 = E394-PN33
18 12 02.5 -33 52 06
V = 11.0; Size 50"x37"
17.5" (6/28/00): at 280x this moderately bright PN appears elongated 5:4 SW-NE, ~50"x40". The surface brightness is pretty smooth and no central star was visible. A UHC filter provides a moderate contrast gain. Set is a rich star field.
13": observation at 166x and 220x: fairly faint, moderately large, slightly elongated ~N-S, no annularity. Prominent using UHC filter, moderate surface brightness. Located in a rich star field 15' ESE of mag 6.2 SAO 209817.
8": faint, elongated N-S, fairly small.
Sh 2-68 = PK 30+6.1 = YM 15 = LBN 93 = Simeiz 291
18 24 58.5 +00 51 38
V = 11.2; Size 475"x330"
17.5" (7/1/00): at 100x using an OIII filter, Sh 2-68 appears a very large, round, low surface brightness glow, perhaps 5'-6' in diameter. Requires averted vision but can be seen readily. The halo has a fairly crisp edge and surface brightness is uniform. Not seen unfiltered.
17.5": at 83x and OIII filter appears as a very faint, very large, roundish glow, fairly sharp-edged. Can almost hold steadily with averted. Located 17' WNW of mag 6.9 SAO 123471. Recent 1983 discovery and possibly a HII region.
M1-64 = PK 64+15.1
18 50 02.1 +35 14 36
V = 13.3; Size 17"x17"
17.5" (6/28/00): picked up at 220x using a UHC filter. Appeared fairly faint but easily visible with direct vision as a small, round disc, ~15" diameter. Also viewed unfiltered and there is a 15th magnitude star at the north edge. At 280x, the surface brightness is irregular and the northern rim appears brighter. With the UHC filter the rim is crisp-edged. The appearance is similar at 380x.
13": at 166x with UHC filter appears fairly faint, small, round, about 15" diameter. At 220x unfiltered, a very faint mag 15 star is just visible on the N edge. No annularity seen at this magnification.
IC 1295 = PK 25-4.2
18 54 36.5 -08 49 49
V = 12.5; Size 102"x87"
17.5" (6/30/00): fairly bright at 220x using a UHC filter as a roundish disc, ~1.6'x1.4'. The surface brightness is irregular and it appears slightly brighter along the SW and NW portion of the rim. The unfiltered view at 280x also reveals a mottled appearance with a mag 13.5-14 star situated right at the west edge and a mag 14.5 star in the interior (a bit offset from center). A couple of extremely faint stars are at the following edge
17.5": bright, large, round, 1.5' diameter. Very pretty at 220x, estimate V = 12.0-12.5. The stellar planetary K4-8 is just 4.6' WNW.
13": the rim on the S or SW side appears brighter but no definite annularity seen.
8": faint, round, fairly small. Located 40' E of N6712 in low power field. Observation mentioned in 10/81 S&T for smallest scope.
5": visible with a 5" stop without filter and easy with UHC at 79x!
Abell 55 = PK 33-5.1
19 10 30.4 -02 21 02
V = 13.2; Size 47"x32"
17.5" (6/30/00): this is a fairly small Abell PN, ~40"x30", oriented SSW-NNE. At 100x using an OIII filter, the object is fairly faint with an irregular surface brightness but no annularity. Also barely visible unfiltered as an amorphous glow.
17.5": fairly faint but visible with direct vision at 105x using an OIII filter as a fairly small, slightly elongated disc. Dimmer view with UHC at 220x. Located 24' east of mag 6.6 SAO 143070.
NGC 6781 = PK 41-2.1
19 18 28.2 +06 32 23
V = 11.4; Size 111"x109"
17.5" (6/30/00): at 220x unfiltered this fairly bright PN has a 1.5' round halo. The rim is brightest and more well-defined along an arc on the S and SE rim. The central 45" hole is slightly darker and irregular in surface brightness. A mag 13 star is at the NE edge and once or twice I caught a fainter glimmer of an interior star north of center.
17.5" (7/12/99): at 100x appears fairly bright, round, ~1.6' diameter with a darker center. I used a variety of magnifications and filters but the most interesting view was at 220x using a UHC filter. With this combination the PN is slightly elongated E-W and clearly brighter along the southern rim with the brightening tapering towards the ends so this brighter portion had a crescent appearance. Because of this asymmetric rim the darker center seems offset and only weakly brightens at the NW rim. A mag 13 star is just off the NE edge 1' from center.
17.5": at 222x and UHC filter; very large, about 1.8' diameter, much brighter on the SW portion of the rim, darker center. A mag 13 star is just off the NE edge.
13": brighter rim mainly on the SW side, slightly annular appearance. A faint star is off the E edge.
NGC 7008 = PK 93+5.2
21 00 32.7 +54 32 36
V = 10.7; Size 98"x75"
17.5" (6/28/00): this beautiful, highly structured PN is situated just north of a wide double star (9.3/10.2 at 18"). At 280x, the annular oval is elongated SSW-NNE, ~90"x65". A bright 30" irregular knot is prominent at the NE end. The SW end of the major axis has a fainter condensation and the rim is clearly dimmest near the double star. The mag 14 central star shines steadily as a does a slightly fainter mag 14.5 on the NE edge. Just off the W edge is another 14th magnitude star. The darker center is faintly luminous and the surface brightness is irregular over the entire oval giving a mottled, wispy appearance.
13": bright planetary with unusual structure and several stars involved. The striking complete annular ring is elongated SW-NE. A mag 14 central star mag is visible as well as a mag 14 star at the NE edge and a faint star is off the W edge. A small brighter knot marks the ENE end. The planetary is located just N of h1606 = 9.3/10.2 at 18" separation.
8": unusual structure, curves south on the west side. A faint star is embedded.
IC 4603 = E517-*N002 = LBN 1109
16 25 26.3 -24 27 57
Size 20.0x10.0
17.5": this is a large, circular glow surrounding a 4' pair of mag 8/10 stars and is part of the Rho Ophiuchi complex (2° N of Antares). The nebulosity extends roughly 8'-10' in diameter. The setting is quite eerie as the 50' field is nearly devoid of all stars - just two other faint stars and the field has a dull gray feel as if it was weakly luminous.
IC 4604 = E517-*N003 = LBN 1111
16 25 35.1 -23 26 50
Size 60x25
17.5": this northern section of the Rho Ophiuchi nebula surrounds 3 bright stars including a mag 5 star and two mag 7 stars 2.5' N and WSW. The glow appears most evident around the brightest star. The dusty surrounding field is nearly empty of stars.
IC 4605 = E517-*N008 = LBN 1110
16 30 12.5 -25 06 55
Size 30x30
17.5": this section of the Rho Ophiuchi nebula surrounds 5th magnitude Rho Oph which has a faint halo. A mag 8 companion is 3.6' SW. As with other sections of the nebula, the surrounding field is strangely devoid of stars and the background has a grayish sheen as if it is feebly glowing.