by Steve Gottlieb
| M30 = NGC 7099 = E531-SC21 | 21 40 22.0 -23 10 45 | V = 7.4; Size 12.0 |
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| 17.5" (8/17/01): viewed at 575x in excellent seeing. Very irregular appearance with strings of stars emanating from an irregular bright, partially resolved core. A prong off the W side heads NW with three equally spaced similar stars with a 4th star a close triple. Another bright line of three stars heads due north with a fainter bent elbow of stars angling towards the NE. Roughly a dozen stars trail to the east with a large gap towards the edge of the halo. A fairly well defined semicircle of stars open to the north passes directly through the core and off the SE side. The outer halo is peppered with dozens of faint stars over a dim background haze and with concentration the overall diameter increases significantly to over 10'. | ||
The supernova remnant G65.2+5.7 discovered in 1997 in Cygnus near Albireo seemed a bit easier than from Fiddletown or the Sierra Buttes in July and Mark Wagner and I could trace the filament nearly 15' in length.
| Sh 2-91 = LBN 147 = G65.2+5.7 | 19 39.7 +29 57 | Size 120x2 |
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| 17.5" (8/15/01): excellent view at 100x and OIII filter. A large, faint threat oriented SW-NE begins near mag 8.5 HD 185735 (V2086 Cygni) and passes south of a mag 9.6 8' NE. Continuing NE the wisp brightens for a few arc minutes and heads towards a wide mag 10.5/11.3 pair. The entire strip extends ~13'x2'. | ||
With good seeing, I jacked up the power to 500x to revisit some compact NGC and IC planetaries that just look like quasi-stellar blurs at low powers or on evenings with only fair seeing
| NGC 6537 = PK 10+0.1 = PN G010.1+00.7 = E590-PN1 | 18 05 12.9 -19 50 34 | V = 11.9; Size 5" |
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| 17.5" (8/17/01): picked up at 220x as a fuzzy mag 12 "star" forming the eastern vertex of an obtuse, isosceles triangle with two similar stars 1.5' W and 2.4' NW. Excellent view at 380x and 500x. Clearly nonstellar at the higher powers, ~5" diameter with a bluish color and occasionally a slightly brighter center. | ||
| NGC 6565 = PK 3-4.5 = PN G003.5-04.6 = E456-PN70 | 18 11 52.4 -28 10 43 | V = 11.6; Size 10"x8" |
| 17.5" (8/17/01): picked up at 100x as fuzzy mag 12 star. Jumped up to 500x in good seeing which provided an excellent view of a crisp, slightly elongated 10" disc with an irregular surface brightness. In steadier moments, annularity was evident and there appeared to be a tiny darker hole in the center with a brighter rim and no hint of a central star. Situated within a rich Sgr star field with a few faint stars within 1' and several brighter stars in the field. | ||
| NGC 6578 = PK 10-1.1 = PN G010.8-01.8 = E590-PN12 | 18 16 16.4 -20 27 02 | V = 12.9; Size 13"x10" |
| 17.5" (8/17/01): Situated within clump of stars at 100x and appeared stellar at low power. At 500x, a small unevenly lit 4" disc was easily visible close ENE [21"] of a mag 11 star. An extremely faint star is just off the SE edge and an evenly matched 20" pair of mag 11 stars lie 1' SE. Located 7' NW of a mag 7 star. | ||
| NGC 6826 = PK 83+12.1 = PN G083.5+12.7 = Blinking Planetary | 19 44 48.0 +50 31 31 | V = 8.8; Size 30" |
| 17.5" (8/17/01): beautiful view at 500x; the disc is slightly elongated WNW-ESE, with subtle structure. There is small, slightly darker region around the bright 10th magnitude central star. The halo dims slightly along the preceding edge with concentration and the edge is not as sharp. | ||
| IC 4997 = PK 58-10.1 = PN G58.3-10.9 | 20 20 08.8 +16 43 54 | V = 10.8; Size 2" |
| 17.5" (8/18/01): the PN appears as an unusually bright mag 11 "star" (V = 10.8) at 100x in a rich star field. Verified with OIII blinking. An excellent comparison star is a mag 10 star just 1' SW. A 12th mag star 2' WSW completes a distinctive obtuse triangle. With the filter the PN is nearly one magnitude brighter than the 10th mag star. At 280x, the PN is bluish and a tiny disc is highly suspected, perhaps 2"-3". | ||
I spent quite a bit of tiny combing the star fields in Sagittarius and Scorpius seeking out stellar planetaries hiding in the amazingly rich background maze of milky way stars. For these, you're pretty lost with just a paper star atlas such as Uranometria or even Millennium. In fact, I found even the computerized charts I brought along made using TheSky were not up to the task in many cases. Fortunately, I had finder charts of virtually all known planetaries in the Strausberg-ESO Catalogue of Galactic Planetary Nebulae. The following obscure PNe, though, were ones with an appreciable disc and relatively easy to identify at lower powers using an OIII filter
| Sa 2-237 = PK 11+7.1 = PN G11.1+07.0 | 17 44 42.1 -15 45 13 | |
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17.5" (8/17/01): this was the second observation of Sa 2-237 in the past
week
and I upped the power immediately to 380x which provided an excellent view.
The central was fairly easy at this power and the elongated glow had an
irregular surface brightness. Extended nearly 3:1 WSW-ENE, ~25"x8". I had
the
impression the nebulosity was weaker around the central star with a brighter
quasi-stellar knot to the ENE.
17.5" (8/12/01): this very unusual bi-polar planetary was picked up unfiltered at 220x as a faint, elongated glow, appearing more like a dim galaxy than a PN. At this power there was a modest contrast gain with a UHC filter. The best view as unfiltered at 280x-380x. This object appeared elongated ~7:2 SW-NE, ~25"x7" and seemed brighter toward the center. At moments a very star seemed involved. Based on the CCD image at http://www.ctio.noao.edu/REU/ctioreu_2001/rudy/PN.html , this may have been the central star or a superimposed star very close north of center. The extensions are reminiscent of the two bi-polar jets in M2-9. Discovered in 1975. | ||
| Sh 2-71 = PK 36-1.1 = PN G035.9-01.1 | 19 01 59.3 +02 09 18 | V = 13.2; Size 124"x75" |
| 17.5" (8/17/01): interesting, large PN at 140x using an OIII filter. The outline is subtle but irregular. Initially it appeared roughly circular, but with concentration a faint extension which sometimes appeared detached is at the south side, giving a N-S elongation. The rim is brightest along the east side and curving around to the north giving a partial crescent impression. | ||
| LSA 1 = PK 29-7.1 = PN G029.8-07.8 | 19 13 55.7 -06 18 52 | V = 15.7; Size 14" |
| 17.5" (8/15/01): faintly visible without filter at 220x and verified with a UHC filter as a small, round disc. Excellent view at 280x and UHC; steadily visible as a crisp-edged, evenly lit 10" disc. Situated 27' SW a mag 6.6 star between 10th mag SAO 143155 3' SSW and a mag 11 star 4.4' NNE. Also 2' W of a mag 11.5 star. The computed visual magnitude of 15.7-16.4 appears significantly too faint. Discovered by Lundstrom et al, 1988. | ||
| Abell 62 = PK 47-4.1 = PN G047.1-04.2 | 19 33 18.3 +10 37 01 | V = 14.7; Size 161"x151" |
| 17.5" (8/17/01): at 100x using an OIII filter, an extremely faint, large, roundish glow was evident with averted vision in a rich star field containing a large number of mag 10-12 stars. The low surface brightness haze seemed 1.5'-2' in diameter. A string of stars interesect the PN near the edge while a brighter mag 10.5 star is off the NW side. The surface brightness appeared irregular and the edge was very difficult to trace but locally brighter on the south side. Without a filter several stars are superimposed in the region of the PN. | ||
| He 1-5 = PK 60-7.1 = PN G060.3-07.3 | 20 11 55.9 +20 20 06 | V = 16.0; Size 30" |
| 17.5" (8/15/01): Although FG Sge is currently below 15th magnitude, there is a mag 12.5 companion ~10" E which was easily identified at 220x as the third of four in a NW to SE 6' chain of mag 12-13 stars. An extremely faint halo ~20" diameter was strongly suspected with this star embedded off-center. With a UHC filter, the nebulosity was more evident although there was only a mild contrast gain. The central star FG Sge is unique as an extremely fast evolving post-AGB star with a late Helium flash and rapidly on its way to the white dwarf stage. | ||
| Abell 70 = PK 38-25.1 = PN G38.1-25.4 | 20 31 33.2 -07 05 17 | V = 14.5; Size 45"x40" |
| 17.5" (8/16/01): picked up at 220x without filter and an excellent view at 280x. The PN appears slightly elongated NW-SE, ~40"x35" with a clearly irregular surface brightness. The galaxy shining through the north side is visible as a brighter "knot", but with extended viewing this enhancement is elongated WNW-ESE, perhaps 15"x8". A faint star is ~30" off the SW side with a brighter star ~45" off the SE edge. Modest contrast gain with UHC filter although the brightening along the N side was more difficult to detect. | ||
On Saturday I left early to take my son to the WWF Smackdown event in San Jose (the highlight of the summer for him!) and stopped at Lake Sonoma on the way back to the bay area -- detouring around Clear Lake -- for quite a gathering and a chance to see David Silva's virgin 14.5" GOTO Starmaster and Robert Leyland's 17.5" Discovery. Two highlights for me were a couple of galaxies just outside the halo of M92. Without a good computerized star chart, you would have just passed right over these ghostly blurs --
| MCG +07-35-055 = CGCG 225-084 | 17 15 15.2 +43 17 23 | Size 0.6x0.3; PA = 0d; B = 15.1 |
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17.5": faint, very small, round, 15", fairly high surface brightness. With
extended viewing there were very faint extensions N-S, increasing size to
25"x12". Two mag 14.8 stars 1.6' NNE and 2.4' NNE are collinear with the
galaxy. MCG +07-35-058 lies 14' ENE. These two galaxies are the closest
galaxies to M92 with MCG +07-35-055 situated 22' NW of the core.
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| MCG +07-35-058 = CGCG 225-091 | 17 16 27.3 +43 20 34 | Size 0.7x0.3; B = 15.3 |
| 17.5": very faint, very small, round, 10" diameter (probably viewed core only). Bracketed by two 15th magnitude stars 1.0' SE and 1.3' WNW. This galaxy is located 14' NW of the core of M92, less than 10' outside the halo of the globular! MCG +07-35-055 lies 14' WSW. | ||