At 100x, NGC 40 appears (unfiltered) as a slightly elongated, moderately bright disc surrounding a bright mag 11.5 central star. A slightly fainter mag 12 star lies 1.0' SW. I
targeted this object because it is an unusually low excitation PN, with an OIII/H-beta ratio of 0.4. In most PNe, this ratio is runs from 10:1 to 20:1. This implies that on NGC 40, the OIII
filter is not the best choice and as predicted there was a noticeable enhancement using the H-beta filter and it dimmed with a 2-inch OIII. At 220x, a star was intermittently visible at the
SW edge and the PN was slightly elongated SSW-NNE. The best filter response using this power was with the UHC. The surface brightness appeared irregular -- darker around the central star
and slightly brighter along the west and east side of the rim. At 280x, the faint star I had earlier noted was barely off the SW edge and PN was weakly annular with a brighter rim along the
west and east side and a darker center. The SW and NE ends of the halo were clearly weaker, though. 380x provided a nice view with subtle irregularities in the interior.
NGC 246 in Cetus
00h47.1m -11d52'
At 100x, NGC 246 appears as a moderately bright, 3.5' irregular glow with a darker center and encompassing four stars including a 12th magnitude central star. Excellent contrast
gain using an OIII filter, which sharpens up the edge of the roundish annulus and enhances the irregular surface brightness. The halo is brightest along the 270° arc running from SW to NE
and is clearly weakest on the E edge of the halo. A mag 11.5 star is embedded at the NW edge of the halo 2.0' from center. The irregular central hole is much darker but faintly luminous.
Also superimposed is a mag 12 star SW of the central star and a 4th star is just inside the eastern boundary. At 220x, the western 90° outer arc is brightest and there appears to be a knot
embedded at the NE edge of the halo.
Abell 4 in Perseus
02 45 +42.6
At 105x and OIII filter appears faint, small, round. Can hold steadily with averted vision, estimate V = 14.5-14.7. Nice view at 220x and UHC filter although visible without filter
at this power. Smaller than most Abell planetaries. Located 40' ESE of M34.
Sharpless 2-188 in Cassiopeia
01 31 +58 24
This huge filamentary complex was discovered at the Simiez observatory in Russia in 1951 and was relisted in a survey by Sharpless in 1959. Jay McNeil provided me with background
information on this interesting object. Both Simiez and Sharpless classified this object as an emission object and at one point it was considered both an HII region and a SNR based on its
wispy appearance (like a dim version of Pickering's Wedge in the Veil). It wasn't until the 90's that Simeiz 22 first appeared in PNe lists and it is now considered an ancient,
crescent-shaped planetary similar to the Medusa Nebula (Abell 21). The best view of this phantom object was at 100x (20 Nagler) using an OIII filter. With averted vision, a large, low
surface brightness glow was visible, elongated ~E-W and perhaps 8' in length with a better defined southern edge. Several mag 13-14 stars are superimposed. It wasn't easy to identify this
planetary (definitely not your garden-variety type).
NGC 1360 in Fornax
03h33.2m -25d52'
This unusually bright and large planetary is elongated 3:2 SSW-NNE, 6'x4' diameter with a striking central star mag 10.5-11. The surface brightness is high and fairly smooth. A
truly striking object with or without filters!
NGC 1514 in Taurus
04h09.3m +30d47'
At 100x (20mm Nagler), NGC 1514 in Taurus displays a round, 2' halo surrounding a prominent mag 9.5 star. There was an excellent response to UHC and OIII blinking and no response
to the H-beta filter (In this case, the OIII/H-beta ratio runs at 12:1). Using the OIII filter, the surface brightness was noticeably uneven, with the NW quadrant of the rim clearly
brighter. The SE side was also weakly enhanced while the center and ends of the minor axis were slightly darker. At 220x using a UHC filter, the halo appears nearly 2.5' in diameter. There
was a small, darker "hole" surrounding the central star and the halo was clearly irregular with a brighter "knot" on the SE side, while the NW portion of the halo was brighter along the
rim.
NGC 1535 in Eridanus
04h14.3m -12d44'
Back in 1980, I logged the beautiful double-shelled planetary NGC 1535 as "greenish", but in several subsequent observations with 13" and 17.5" scopes it has appeared blue to me.
Has anyone noticed a perceived color difference based on aperture (or possibly aging eyes?). This PN has a wonderful double-shell structure which was easily visible at 100x surrounding the
bright central star. The view at 380x and 500x is superb in the good seeing. The double shell envelope is very prominent with a bright inner ring ~20" diameter with a fairly sharp edge
embedded in a fainter roundish halo roughly doubling the diameter. The inner shell is irregularly darker surrounding the central star (I've previously described this structure as "small
dark gaps" in my observing notes).
IC 418 in Lepus
05h27.5m -12d42'
The diminutive planetary, IC 418 in Lepus, has gained some notoriety lately because of reports of a unique pinkish hue. I've noticed this coloration twice, but the effect is pretty
subdued to my eyes. At 82x, the mag 10.5 central star was enveloped in a very small round halo which appeared to have a slight reddish tinge at its edge. Once again, this is a
low-excitation planetary (OIII/H-beta = 1.2) and using a H-beta filter, the halo brightened while the central star dramatically faded, leaving a more noticeable disc. At 220x, the prominent
central star was surrounded by a well-defined 10" halo which partially "blinked" on and off by switching from averted to direct vision. At 280x, the small halo was possibly surrounded by an
extremely faint envelope, but this could not be confirmed, 380x and 500x presented a superb view of the inner disc which appeared weakly annular.
Abell 12 in Orion
06 02 +09.7
At 220x and UHC filter; moderately bright, round, moderately large. Difficult to view as overpowered by glow of mag 4.1 Mu Orionis 1.2' WNW! Easier at 294x which cleanly separates
the pair, estimate V = 12. Takes 412x which puts more room between Mu and Abell 12.
Abell 21 in Gemini
07 29 +13.3
At 100x and OIII filter the "Medusa Nebula" appears moderately bright, very large with a distinctive thick "horseshoe" shape open to the W. The S and SW portion of the rim are
brighter and the rim is incomplete on the W and NW side. A brighter star is embedded in the NE portion of the rim.
NGC 2371/72 in Gemini
07h25.6m +29d29'
The appearance is very unusual at 380x with two bright knots oriented SW-NE about 30" between centers. The SW knot is 15"-20" in size, slightly elongated and the brighter of the
two. The NE condensation has a slightly lower surface brightness and appears ~20" in diameter. Symmetrically placed between the knots is a faint 14th magnitude central star. Weaker
nebulosity connects the two knots giving a dogbone appearance and a faint rounder halo encases the structure.
Jones Emberson (JE) 1 in Lynx
07h57.8m +53d25'
At 82x using an OIII filter this huge annular planetary is slightly elongated with two brighter "knots" along the rim. These appear as large enhanced arcs with the SE arc the most
prominent. A pair of small galaxies NGC 2474 and 2475 lie 33' south.
