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by Jay Reynolds Freeman
I took Harvey the Celestron 14 to Fremont Peak on the evening of Saturday, 5 June 1999, and set up in an unobtrusive corner of the southwest lot. One advantage of my tiny little C-14 is that all the lines form at big Dobsons: The fog was in on the coastal plain between Monterey and Santa Cruz, the weather would have been almost shirt-sleeve if it weren't for a touch of breeze, the sky was clear, and I wanted to get in lots of viewing of my own.
For once I was there early. I took a break from setting up to look at Venus, an easy naked-eye sight in the pellucid sky an hour before sunset, even with dark glasses on. Hey, I had to do something to keep the sun out of my eyes. In early twilight, someone spotted Mercury, a few degrees above the western horizon, equally easy for the naked eye against the darker sky of the beginning of evening.
My first telescopic view was Mars, at 98x and 244x. Poor seeing made it disappointing. I was not sure whether the problem was the atmosphere or my Kendrick anti-dewing system, which I was running at "medium", since the relative humidity was over 60 percent and climbing, and the temperature had only begun to fall to nighttime equilibrium. Mizar and epsilon Lyra split easily at 244x, but the stellar images were too much in motion to see diffraction rings.
While the sky was still too bright for lower magnification, I chased down M57 and M51 at 244x. The Ring Nebula was very bright, and showed slight fuzziness at the "pointy" ends of its fat ellipse. Even in twilight, the relatively high magnification allowed a glimpse of spiral detail in the Whirlpool, as well as of the bridge to its companion, NGC 5195. M13 was resolved wide open at that magnification, and nearby galaxy NGC 6207 showed elongation and hints of further detail. By that time, the sky was getting dark, so I settled down to the more serious part of the night's program.
I have a "Cats and Dogs" list, a computer file of interesing stuff I have not seen, assembled catch-as-catch-can -- cats and dogs are like that -- from diverse sources, sorted by right ascension. I print it out from time to time to stick into my observing notebook and take to star parties. At the moment, it contains some 300 objects, widely distributed. Leo and its environs were moving into evening twilight, so I started down the list from about ten hours right ascension.
One interesting thing to do with small telescopes is look for NGC objects now thought non-existent, to try to find out what their original discoverers were seeing. Objects once thought open clusters often prove interesting asterisms or chance groupings of stars. I looked at two: NGC 3129 comprised four or five stars within a few arc minutes, and NGC 3401 was perhaps four times as many, over twenty arc minutes.
That same band of right ascension contained several Hickson galaxy groups that I had not seen before. Hickson 51 showed two NGC galaxies at 98x, and at least four more at 244x. Hickson 56 showed as a bit of fluff at 98x, no doubt dominated by one MCG galaxy, but I misread my printout and did not think to drop in more magnification to look for a few others that might have been visible. This group is near the brighter galaxies NGC 3718 and 3729, but those aren't the ones I missed.
Hickson 57 was an interesting compact grouping: It has a name as well as a number, this is Copeland's Septet. At 98x it was visible as fuzz, but 244x revealed at least the six NGC galaxies (including one object with two NGC numbers attached to it) that are shown on Millennium Star Atlas. This is a fun object -- three of the galaxies are so close they all but merge, even in the 244x field. Hickson 58 had five galaxies, more widely separated, easily distinguished at 98x.
While thumbing through my notebook, I accidentally opened it to a printout of local galaxies, that includes lots of will-o'-the-wispy little dwarfs. I have been having good luck chasing these during the last few years, so I decided to try a difficult one that happened to be riding high; the Ursa Minor Dwarf, not far from the bowl of the Little Dipper. Deep images of this object show a cosmic ghost, a thin smear of stars left over from a single wave of star formation, long ago, whose first harvest of bright suns blew all the rest of the raw material out of the system, and so generally precluded additional stellar creation. What stars are there are old, dim, population II stuff, with no HII regions or illuminated dust and gas to draw the eye.
Near the center of the ellipse that Millennium plots, 98x showed a diffuse, hazy patch, much smaller than the ellipse -- I might have said five arc-minutes diameter, very faint but repeatably detectable when I swept away and then returned. Positioning the field north of the plotted location and sweeping slowly south, looking for a subtle sensation that the background glow had increased -- a technique brought to my attention by Stephen O'Meara's recent book on Messier objects -- consistently revealed a contour that tolerably matched the northern boundary of the inclined ellipse, but I could not similarly distinguish the southern boundary. I decided to log the galaxy as seen, but this was an observation rather on the edge, and I shall be curious whether anyone else has had similar experiences with this toughie.
At one point, I heard chewing noises coming out of the darkness on the side away from the setup area. I shined a light in their direction, nervously hoping not to see eyes. No luck -- a bright pair of ferocious red orbs glared back at me from shoulder height, uncomfortably nearby. But they were red only because my light was, and high only because the raccoon had climbed onto a picnic table to liberate goodies. Later the animal walked past my feet, but was more interested in cookies in peoples' cars further along, than in a look through Harvey's eyepiece.
My cats and dogs included a couple of Abell clusters: A1185 was pretty easy -- Millennium plots a handful of NGC galaxies, all no trouble for Harvey. Yet nearby A1213 was an undistinguished bit of fluff at 98x. Such objects are frustrating at higher magnification, for there almost always appear to be all but indetectable details and lumps hanging at the limit of visibility, which are probably for the most part real, but are nevertheless very difficult to nail down.
I looked at a handful of isolated galaxies, too, and tried Mars once more to see if the seeing had gotten better. It hadn't, but the relative humidity had soared beyond 90 percent, so I had dialed the Kendrick to "fricassee", and perhaps that was the difficulty. By the way, anti-dew systems are wonderful, I can't imagine how I got along without one before. (The answer is, that mostly I didn't, I just shut down and sat in soggy gloom.) The roof of my car was wet, the seat of my observing chair was wet, and in consequence the seat of my pants was wet, but the corrector plate was bone dry. Maybe I should have been sitting there.
The summer Milky Way had risen high enough for easy viewing, so I visited a few old friends. Near-swimmable humidity notwithstanding, the transparency seemed excellent and the sky very dark. At 98x, I saw far wider extents of nebulosity in M8 and M17 than I am used to. The "eagle" (sort of) shape of the nebulosity in M16 was obvious, and the complex dark mass that I think of as the Star Queen on her throne was easy to see, even at this low magnification. (There has been some controversy about whether the name "Star Queen" was intended to apply to this mass or to the bright strew of stars nearby. My vote is for the dark nebula, but I acknowledge that others disagree.)
I started taking my equipment down about half an hour before Moon rise, and was home relatively early. It was a wonderful night, and the lines of would-be viewers all stayed at the big Dobsons. Maybe we are going to have decent viewing this summer after all.