This past Monday and Tuesday nights I observed from my red zone backyard. SQML ranged from 18.3 - 18.5, which equates to Naked Eye Limiting Magnitude of 4.2 to 4.4. I was driven mainly to keep up with my Astronomical League H2 and Planetary Nebula lists. I have fallen behind on the lists due to cloudy weather this winter; the "next up" targets are all well past meridian. It has made me resent the lists somewhat -- why shouldn't I just observe whatever I want? But I do want to finish what I started, and I do want the validation which would come from completing the program. These lists are rather like college level classes, and if I complete the H2 I suppose I will have enough "credit" to have graduated.
In any case, the experience was a lesson in how light pollution affects the views. Surprisingly all but the most diffuse planetary nebula were viewable, as were the open clusters. Of course these would appear brighter, with more detail or more stars, in a darker sky; but they could be seen nonetheless. But the galaxies were hit hard. The galaxies on the H2 list have integrated magnitude of 13 or so, and in a dark sky are bright and obvious in the eyepiece, often yielding subtle detail. In my back yard they were threshold objects for which I needed to work hard to see. And this with a 20-inch telescope -- they would be quite out of reach of my 12-inch or 8-inch. In the coming months I could continue to observe from the back yard, but I should prepare myself for a frustrating experience.
Here are my notes:
NGC 2259, Open Cluster in Monoceros: @ 205x: Pretty arrangement of stars. Bright red star to the W. Bright white in middle with a few more fainter stars boxing it in. Three in SW make a triangle pointed NE. Faint stars come into view with AV, especially a close pair to SW of the center star. Stars mostly E-W. Did not see nebulosity. II1pn
NGC 2261, Reflection Nebula in Monoceros: @ 205x Hubble's Variable Nebula. Wow, interesting! Looks like a comet with a wide, faint but short tail, with a star as the comet nucleus. OIII loses it altogether, but UHC dims the point star but elongates the tail. I will come back to this over the years and try to note its changes. NGC 2264 the Christmas Tree Cluster is nearby, stopped for a look through the 50mm finder.
NGC 2274, Galaxy in Gemini: @ 205x: Very faint, threshold object. But I can see a small bright round core with a just stellar nucleus; halo is a faint round haze. There is a hint with AV of a second hazy core just to the north [this is NGC 2275], slightly elongated NNW-SSE, half the size of 2274
NGC 2331, OC in Gem: @ 121x: Coarse, large cluster, about 30 stars with medium range of brightness. A loose circlet of 5 stars to the east. "Y" shape overall, like the Hyades. A red star just SW of center. IV2m
NGC 2339, Gx in Gem: @ 121x. Very faint, AV only but can hold a brighter core with a suggestion of halo 3:2 N-S. Lies in a fine rich field of stars.
NGC 2415: Gx in Lynx: @ 121x: Faint oval glow, with a brighter center, in a line of three stars. A nice close double star is midway to the edge of the FOV to the north.
NGC 2493, Gx in Lyn: @ 121x: Seen DV but barely. AV brings out barely oval core with some mottling, and suggestion of round halo. Bright red star to the NE.
NGC 2500, Gx in Lyn: @ 121x: Excessively faint round haze, seen AV only. Diffuse -- no core noticeable. In a diamond shaped asterism.
NGC 2541, Gx in Lyn: @ 121x: Extremely faint streak, small. AV shows stellar nucleus, very diffuse halo 2:1 NNE-SSW
K2-2, Planetary Nebula in Mon: @ 205x: Faint bloated star suspected to be the PN. With OIII there was a small faint round shell with a central star -- the shell appeared best while blinking. It is at the base of a mini Big Dipper asterism
M1-7, PN in Gem: @ 205x: Can't believe I got this one in a red zone. Unfiltered appears as a bloated faint star. OIII shows it as a faint, small hazy ball with soft edges, slightly green. No CS.
NGC 2371, PN in Gem: @ 205x: Unfiltered appears as an irregular grey glow. With OIII two lobes appear--kissing orbs--both greenish. 2271 is to SW, the fainter 2272 is to NE. Stars appear in both lobes but they are not centrally placed; CS is supposed to be in geometric middle but was not seen.
NGC 2392, PN in Gem, @ 205x: Unfiltered can see CS with a round grey glow around it; a close-by star to the N. OIII loses the CS but shows the ragged outer fringe and mottling inside the shell, especially a bright inner shell rim on the NE side.
I made attempts at Abell 21 (aka Medusa Nebula) in Gemini on both nights, but I can't claim it. My sketch shows the correct star field, but I drew a small glow -- when I looked at images after the session I see it is a large, thick C shape. I suspected a large round but excessively faint glow, but it was so obscure I didn't pin it down as the nebula. Now that I know what to look for I will give it another try.
It's cloudy this new moon weekend, so very likely I will need to try the back yard again.
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