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On Saturday afternoon I packed up late and drove through the hazy central valley to cleaner skies in the Sierra foothills near Fiddletown. Transparency was down perhaps a half a magnitude to 6.0 but the mild conditions and often sub-arcsecond seeing more than compensated making for a very enjoyable evening.
We had a small gathering including Ray Cash, who was playing with his new Fastar 8 CCD set-up and Dennis Beckley, who worked on the Herschel list. As the milky way started brightening, Dennis mentioned that Comet Lee and 1993 S3 (Linear) were just a couple of degrees apart in Cassiopeia and easy targets. They're comparable in magnitude and an interesting contrast in surface brightness.
Cassiopeia is home to several interesting large HII complexes within a few degrees of each other including N896, IC 1795, IC 1805 and IC 1848.
First up was IC 1848 which is not a well-known visual target. At 100x, IC 1848 appears as a large but weak grouping of stars dominated by a 2' pair of mag 7/8 stars which are both surrounded by several close, faint companions. The surrounding 1 degree field is undistinguished but is weakly concentrated around the bright pair. Faint nebulosity is weakly glows in portions of the field. At 220x, the view is striking with ~12 stars huddled around the southern mag 9 star including a nice pair of mag 12 stars nearly collinear and equally spaced. The brighter mag 7 star (…306) is surrounded by 8-10 companions. The 20' field is fairly rich but scattered with a matched pair of mag 9 stars ~10' N.
Using a UHC filter at 100x, the field is emmersed in a very large, faint nebulosity about a degree in length, elongated E-W. A large, bright region elongated N-S is at the east end ~35 following the core and seems detached from the main cloud. It surrounds a weak scattered group which is void of stars in the center. The main body of nebulosity has a sharper border and is generally brighter to the north of the core and fades into the background on the south side. The outline is interesting on the north side with irregular extensions and bulges. A small brighter circular patch stands out at the west end about 10' W of the core.
The rest of the evening was spend chasing down some faint IC galaxies and looking for detail in planetaries at 500x. When the moon rose after 1:00 AM I swung over to Jupiter resigned to losing dark adaptation but was immediately surprised at the easily resolved 1.0"-1.7" discs of varying sizes of the three Galilean moons at 280x-500x (Io made an appearance later in the night). The seeing was clearly exceptional and it was hard to tear away from Jupiter and Saturn. Dennis and I spent the next couple of hours scrambling around the sky resolving doubles. My 17.5" was just loafing on Iota Cass (2.5"), Zeta Ori (2.3"), Alpha Psc (1.8"), Eta Ori (1.6"), 20 Dra (1.3"), 10 Ari (1.2") which were all easy, clean splits (at full aperture and 6" mask) but unfortunately we lacked a good list of sub-arcsecond doubles to split -- a rare activity for my tastes but well-suited for this night.