Last Saturday night a small group met at the Fiddletown observatory located on a ridge in the Sierra foothills east of Plymouth. David Silva and I carpooled together and arrived in the late afternoon to find a couple of regulars already set-up and raring to go after an extremely windy Friday night which apparently played havoc with Charlie Stifflemire's 20" Sky Designs scope. Fortunately, except for some wispy threads of smoke on the extreme southern horizon we had excellent transparency, good seeing and reasonably warm temperatures all night.

Last month at Fiddletown Ray Cash accidentally ran across Sharpless 2-157 which is a huge HII region not far from M52 and the Bubble Nebula. I wanted to check out this region more leisurely this month. The nebula was surprisingly easy at 100x using an OIII filter. It appeared as a faint, curving, graceful arc - very elongated N-S and bowed out on the following side. It extended north and south of a small open cluster, Mrk 50, which is off the W side. I'd estimate the size as 35'x8' with the brightest section showing subtle structure located near Mrk 50. A bright knot, Sh2-157a = Lynds Bright Nebula 537, is situated beyond the southern end of this arc.

This knot was also picked up at 100x as a faint, ill-defined glow surrounding a mag 11 star with a couple of fainter stars possibly involved in the nebulosity. I had a good view at 105x (19mm) using an H-Beta filter which dims the illuminating star. The nebulosity appears circular, fairly crisp-edged, ~2' diameter. At 220x without a filter, the diameter increases to nearly 3', although the edge blends into the general haze of the huge HII region Sh2-157. The central star has a mag 13.5 companion close NW.

Markarian 50 (also referred to as Basel 3) is a tiny group of ~10 stars within a small semicircle and is situated off the preceding side of Sh2-157. The brightest star has a very faint and close companion close following. There is a very small distinctive group of four stars within the semicircle consisting of two mag 12.5 stars with mag 14-14.5 companions about 10"-15" south.

Before leaving the area I took a look at NGC 7510 which is a very pretty triangular wedge of stars in a 5x2' group. There are brighter stars at the western and eastern vertices with the brightest star at the following end. Within the triangle are two dozen stars oriented SW-NE with a number of mag 14-15 stars on the eastern side. Just following the main grouping are another 8 or 9 stars which may be part of the cluster.

Next up in my 17.5" f/4.4 Dobsonian were a couple of compact planetary nebulae in Cassiopeia. Vyssotsky 1-1 is a 1942 discovery located at 00 18 42.2 +53 52 20 (J2000) and <5" in diameter. First I verified it at 100x using OIII blinking and noted the planetary exhibited an excellent contrast gain with the filter. At 220x, it appeared as a "out-of-focus" mag 12.5 star just 1.0' ENE of a close mag 11/12 double star (the components are at 3.7" separation). At 280x and 380x the planetary was clearly nonstellar with a bright center but the central star was difficult to view due to the high surface brightness of the disc and was just visible at 380x. At this magnification a third faint companion to the close double was visible.

Humason 1-1 was a 1920 discovery by Milton Humason, famous for measuring redshifts at Mt. Wilson and Mt. Palomar. This was slightly brighter than Vy 1-1 and also displayed an excellent contrast gain at 100x with OIII blinking. The planetary appeared mag 12.0-12.5 with a slightly soft halo at this power. At 280x a well-defined 5" disc was visible of fairly high surface brightness. A trio of mag 11.5-12 stars roughly collinear are 1'-2' NW.

The last couple of months I've taken a look at M31-G1, which is the brightest globular in the Andromeda Galaxy and I returned to this field again (00 33 41.9 +39 32 41), but this time to pick up UGC 330 which is a faint galaxy just 11' ESE of the globular. Although the DSS shows this galaxy to be quite elongated it appeared very faint, small and only slightly elongated NW-SE with weak concentration (probably only viewed core). A couple of mag 14.5 stars were within 1.5'. Just 4' NNE was mag 8.8 SAO 53990.

After going through most of the 100 entries in the Hickson Catalogue of Compact Galaxy Groups, I've started another run through to see if I can pick up any of the fainter groups which were missed the first time. First up was Hickson 3 and this provided nearly an hour of hunting around due to the lack of any brighter stars to identify on my Guide Star Catalogue finder chart. First I ran across MCG -01-02-034 accidentally which is located 21' SSE of the group. Finally I tracked down one member but was again confused until I realized that I had Hickson 3b and not the primary member designated by Hickson (most have a higher surface brightness). This 15.5 mag galaxy appeared very faint, very small, round, 25" diameter with a mag 13 star 2' ENE. It was this nearby mag 13 star that pinned down the identification. If anyone wants to give this group a try it is located at 00 34.4 -07 36 (2000).

Well, after hunting for a couple of faint fuzzies, I wanted to relax with some brighter stuff and took a look at NGC 281, a great-looking HII region in Cassiopeia. An OIII filter coupled to a 20mm Nagler (100x) provided a spectacular view of this detailed HII complex. Overall NGC 281 has a mushroom appearance about 15' in diameter and separated into three main lobes apparently by dust. The brightest and largest lobe is following a triple star embedded near the center and there appears to be a much fainter detached piece off the south end of this lobe. Preceding the triple star is a section which is noticeably elongated and irregular in surface brightness fading to the NW. The section to the north is the faintest and separated from the eastern lobe by a curving dark lane. There is a dark intrusion south of the triple star which appears to be due to obscuring dust. By the way, E.E. Barnard discovered this one on November 26 1881.

Another interesting nebulous region was NGC 7129 in Cepheus - a 3'x2' reflection nebula of fairly high surface brightness surrounding three mag 9.5-10.5 stars at 220x. At 280x, the brightest region surrounds the southern star (also the brightest star) and the star to the NE. Just preceding this second star is a small knot which does not appear to be surrounding a star. A third involved star on the preceding side has the weakest halo. There is an additional pair of stars nearby to the SW but they don't appear to be surrounded by halos. The entire group is encased in a diffuse glow and the surrounding region appears to be dusty. IC 5132/5133 are very weak nebulae surround mag 12 stars ~5' NNW.

Last up was a controversial object, Sharpless 2-155 in Cepheus, which is dubbed the "Cave Nebula". Patrick Moore undeservingly dignified this faint HII region in his "Caldwell Catalogue". You have to seriously question whether he ever viewed this difficult object! It was best seen in my 17.5" at 100x as a large, diffuse glow mostly surrounding mag 8.5 SAO 20334 (22 56.8 +62 37) and extending north towards mag 7.6 SAO 20335 located 7' due N. I tried using OIII and H-Beta filters but neither provided a noticeably improved contrast. The only structure visible was a very small knot less than 3' ENE of the mag 8.5 star. At 220x this locally brighter spot was clearly seen as a faint 1' roundish glow. This may be an interesting object photographically but visually it is a challenge just to view.

After we all took a quick look at the Horsehead nebula, by this time well placed in the southeast, we called it a night.