Fr.Peak, 26 July (Weds) -- shorts and t-shirt

by Bob Jardine

It was a nearly perfect night at the peak. Warm and dry -- I observed in shorts and a T-shirt until about 2:30 AM. I left then (with regrets) only because I had to work the next day. There was fog covering the lights around Monterey bay, so it was a little darker than average, although it wasn’t a completely dark blanket. The sky was completely clear, and the seeing was good to very good.

I arrived at the SW lot just after sunset. Peter Natscher was already there, and Jamie Dillon arrive shortly after. Small group, but nice company.

We all started out looking at Jupiter before dark. Nice detail. There were two large (long, thin) white ovals just South of the NEB, and a very dark spot separating the two ovals.

I observed mostly Planetary Nebulae, one asteroid, and a couple of bonus galaxies that got in the way. Observations were with my 12.5” f/5 Mag1 Portaball.

Darkness and transparency were interesting. I got 21.10, 21.19, and 21.24 on the SQM as the night progressed -- dark, but not terribly dark. But I got 20-22 stars in Boo-CrB and 12 stars in Peg later. These correspond to mag 6.1 and 6.3, respectively. But at SSP, I was seeing consistently mag 6.2-6.3, but I was getting 21.60 to 21.70 on the SQM. So it was definitely darker at SSP, but the transparency was outstanding at FP on this night, so I could see almost as deep.

NGC 40 -- PN, Cep -- Pretty small, quite bright, very bright central star. Fuzzy, ragged edge, not a “sharp”-edged disk. 176X and 226X.

IC 4593 -- PN, Her -- Very tiny, nearly stellar. In fact, it does appear stellar without a filter (maybe seeing only the central star without filter? or is the PN just so small and bright that it looks stellar?). Overall, pretty bright; difficult only because it is so small.

NGC 6058 -- PN, Her -- Seen as a non-stellar fuzz, roundish, at 176X. Going to 226X, the central star is seen 50% of the time by staring at it (and the fuzz fades). O-III filter makes the central star disappear, while the round fuzz stays put.

NGC 6884 -- PN, Cyg -- Very tiny, barely non-stellar even at 226X. Blinking with O-III is dramatic; everything else in the field goes away. Slightly blue color.

25 Phocaea -- Asteroid, Peg -- easy location in field with 78 Peg; about mag 10+.

NGC 7752/53 -- gals, Peg -- in same wide-field view (35mm Pan) as the asteroid 25 Phocaea. Just barely visible in the 35 Pan with AV. At first, with 176X, I saw only one galaxy here, shape uncertain, but not much brighter center. Slowly, I though I saw elongation, maybe 2:1, NE-SW. By staring some more, I finally saw a second smudge, dimmer and smaller, very near the SW tip of the larger one. Finally, I got a hint that the smaller galaxy was also elongated, with a different PA than the larger one, closer to due E-W. Interesting pair. 7752 is listed at mag 15; I'm sure I would not have seen it on many nights, but it was there this night, because of the combination of great transparency and good seeing at the same time.

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