by Matt Tarlach
Last night Ken Sablinsky and I went up to try the Stockton A.S. high altitude site at Peddlers Hill. Very nice site, with good access off Hwy 88 at around 6900' elevation.
Skies were clear and quite dark throughout the night....I did not have the appropriate limiting magnitude chart to do a careful rating but would confidently rate the skies as mag 6.5+. Seeing was only fair, with 212x (9mm Nagler) the highest power used to advantage on most objects. There was also a slight breeze out of the NE, which became gusty enough after midnight to spoil Ken's efforts at imaging, and even "weathervaned" my heavy dob a few times.
I viewed a few dozen objects in my 12.5" Astrosystems dob, and will only report on the notable observations here:
NGC6445, PN in Sagittarius: At 212x this small planetary appeared boxy in shape, with a dark center. The northern lobe was noticeably brighter than the rest of the nebula. Contrast of the dark center and brighter northern lobe was enhanced by the OIII.
Abell 70, PN in Aquila: This is a tough one, requiring fine skies....I have only seen it once before, from Bumpass Hell on a really good night. Unfiltered at 212x, the nebula is a small roundish glow glimpsed directly but best seen with averted vision. The northern side is much brighter than the rest of the nebula. With an OIII, an almost evenly illuminated, clearly annular shape appears. The bright northern "lobe" is in fact a background galaxy shining through the nebula, which is blocked by the OIII filter.
M73, asterism in Aquarius: One of Messier's "mistakes," this object is notable only because this was the first time I sought it out. It is a compact triangle of four stars, all whitish. At 112x I thought it looked a little "fuzzy," and could see how old Charlie was fooled.
NGC7479, GX in Pegasus: A fairly bright, very elongated spiral galaxy, slightly condensed, with one arm brighter and hook shaped under averted vision. 112x (17mm Vixen LVW).
Pegasus I Galaxy Cluster: Two small but fairly bright, slightly elongated galaxies catch the eye at 112x: NGCs 7619 and 7626. They both condense suddenly to bright nonstellar cores. Examination of the field quickly turns up a third galaxy nearly in line with the first 2 but somewhat removed; it is NGC7631, somewhat bright, substantially elongated and less concentrated at the core. Casual sweeping also reveals 2 more smaller, somewhat faint, unconcentrated, elongated blurs: NGCs 7611 and 7623. NGC7623 features a bright spot, slightly offcenter, that may be either a bright core or a foreground star. Careful consultation of the finder chart in TNSOG leads to identification of 4 more faint galaxies for a total of 9 in the cluster; best viewed at 160x (12mm Nagler).
M31: A really nice view, offering two dark lanes crossing in front, substantial mottling in the arms of the galaxy, and great views of the bright companion galaxies and NGC206. But the real fun started when I found in my chart box an old computer printout describing a starhop to some of M31's brightest globular clusters. Starting from M32 we located G76, C107, G52 and G119. G76 was the easiest, held easily with averted vision, and about 50% of the time directly; at 212x it appeared barely nonstellar in moments of steady seeing when the foreground stars sharpened. C107 was fainter, only glimpsed directly but still easy with averted vision. It appeared more obviously nonstellar, like a tiny gray planetary nebula. G52 and G119 were more difficult, each seen 50% of the time or less with averted vision. In those moments they were also detectably nonstellar, though if I didn't know what I was looking at I wouldn't say it for certain.
M33 in Triangulum: A really nice view, with clear spiral structure at 70x (27mm Panoptic). Bright condensations NGC604 and 592 were easily identified, and the entire galaxy was filled with lumpy detail. I've already decided that sketching M33 and identifying as many of the bright HII regions as possible will be one of my projects for this Fall.
At 2AM we turned in, as the wind was rising and I at least was starting to get too cold to enjoy the viewing. I'd forgotten how much colder it gets at altitude on clear nights, and failed to pack enough warm and wind-blocking layers. I'll be better prepared next time!