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by Jay Reynolds Freeman
A little after sunset on Saturday, 17 July, 1999, I drove into the southwest parking lot at California's Fremont Peak State Park. I was late because I had been at the Peak the night before, had not gotten to bed until 5 AM, and had slept well past noon. I had worried about finding a place to set up, arriving so late, but a lot of the regulars were observing in the Sierra Nevada, so the lot was emptier than usual. I found parking in the northwest corner, backed in, and unloaded Harvey, the invisible pooka seen by some as a white Celestron 14. A five day moon hung low in the western sky, low fog covered much of the coastal plain from Santa Cruz to Monterey, the temperature was warm, and the wind calm. It looked like we were in for a good night.
Part way through setup, I looked down to find a raccoon at my feet, nosing into the nylon duffle bag I use to carry the extendable legs for Harvey's Losmandy G-11 mounting. I cocked a doubtful eye at the curious creature. "There's no food in there," I advised the little animal.
The creature stared back for a moment. "I just wanted to be sure," it said, and ambled off. Hey, I didn't say we were speaking English.
Actually, I did have some food in the car -- a tightly sealed plastic container of dry cat food, for just such occasions. I thought briefly about opening it and leaving a handful for the ring-tailed mischief-maker, but decided not to -- habituating animals to humans is usually not good for them, though with raccoons, it is probably unavoidable.
My setup was finished while the Moon was still high enough to observe, so I put in a 16 mm Brandon -- 244x -- and took a look. The terminator was not far (selenographic) west of Cauchy. Seeing was not perfectly steady, but if I waited patiently, I could see all of the detail in the large version of the Rukl atlas, and more besides, in the domes to the northwest. Then I examined Fracastorius, a huge, half-flooded crater on the southern edge of Mare Nectaris. I could see a lot deal of detail on its floor, including all of the craters the large Rukl atlas charts, and the portion of the rille crossing the floor, that lies west of the "M" craterlet.
I find rilles fun to look at, mostly because they are challenging. The night before, when the terminator lay somewhat west of Petavius, I looked at the floor of that great crater. It has one prominent and well-known rille, radiating straight out southwestward from the central peak, all the way to the wall, but there is a less obvious extension of it, or perhaps a wall or low ridge, that extends a little way northward from the central peak, and there is also a much more difficult set of rilles, that join in a 'Y' pattern, on the eastern portion of the crater floor. I saw all of these features, at 244x.
Last time I checked, no one was completely sure what rilles are. Subsided areas over collapsed lava tubes are one plausible explanation, yet giant Moon gophers might create similar features by their tunneling. Or -- now that we have discovered water at the Moon's poles -- perhaps we should consider the possibility that they are part of an irrigation system, artificial constructs built by long-dead Lunarians to bring water to an increasingly arid world...
Oh, well, the raccoon thought it made sense.
I was not enough interested in the Moon to watch it for long, so eventually I was caught in the classic bind of the deep-sky observer trying to stretch the dark run -- what shall I look at till the Moon has set? I had faced that problem the night before as well, and had looked at a few double stars and at some Messier clusters, both open and globular, at moderate magnification. Objects that resolve into stars reasonably well are little bothered by moonlight. Yet on the second night of the weekend, I was running out of bright globulars.
I remembered that I had started my wrap up of the "big" Herschel list, two years ago, by chasing down galaxies in my 6-inch Intes Maksutov, using about a 1.5 mm exit pupil, while a fat crescent Moon lay high in the sky. Perhaps the same approach would work to view diffuse deep-sky objects in moonlight with the C-14. Still at 244x, I pointed Harvey at M108 and M97. The former was clearly visible as an elongated, mottled streak. The Owl Nebula was round and easy to see, though I could not detect its eyes. Turning the telescope to M51, I was rewarded with a fine view; even though the galaxy lay well down toward the horizon, I could see several spiral arms, including the bridge to companion NGC 5195. The smaller galaxy appeared unsymmetrical, just as in most photographs. The detail was so surprising that I thought for a while I was imagining it, or perhaps that I had been talking too much with raccoons, but no, it was really there.
So I decided to try some more difficult galaxies. I started with IC 1296, which lies a few arc minutes northwest of M57. Sure enough, there it was, faint enough almost to require averted vision, but no real problem with the big Celestron at 244x. Thus inspired, I scanned through Millennium Star Atlas idly, looking for other galaxies in the same part of the sky. I ended up looking at six faint NGC galaxies in Lyra, as well as five from the UGC catalog. None of them appeared remarkable, and I had not seen any of them before.
As I observed, I realized that my guilt over not feeding my furry nocturnal visitor was misplaced. Exclamations and scurrying noises marked the raccoon's thorough and systematic passage up and down the rows of parked cars. Like a shoplifter at the Mini Mart, the masked marauder was stealing supper a bite at a time, wherever someone wasn't looking. With expletives deleted, the commentary suggested that several pieces of fried chicken had been stealthily devoured, as well as the box they came in.
Presently the Moon set, and I switched to a big 40 mm Vernonscope Erfle eyepiece, giving 98x, to look for objects of lower surface brightness. Jim Shields recently posted lists of some of the easier diffuse nebulae from the Sharpless catalog on his web site, at "http://www.angelfire.com/id/jsredshift/". I have been going through these a few at a time during the last several nights out. Many are large, low-surface-brightness areas that are perhaps as much overlooked as difficult. A good narrow-band nebula filter helps -- I used an Orion UltraBlock for about half -- and some are very tough, such as the winter-sky object Sharpless 2-240, also known as Simeis 147. Yet for many of them, the key is to realize that you are looking for a quite large object -- several degrees across in some cases -- and use appropriate techniques, such as sweeping the telescope, or looking for changes in the "background" sky brightness. Sh 2-1, in Scorpius, for example, extends faintly and irregularly over an area several times the width of my 98x eyepiece, yet by these means I was able to trace most of its central and southerly portions.
Everyone commented how dark and relatively warm it was, and several folks also mentioned that the seeing was good. I took a look at epsilon Lyr when it was high overhead, and though conditions were not quite steady for the C-14, I got occasional glimpses of diffraction rings around all four stars, at 244x. I also saw four stars in nu Sco, but the seeing that far away from the top of the sky was much worse. I had a nicely resolved view of zeta Aqr, and a colorful one of epsilon Boo. Harvey was just loafing with these stars; my C-14 has worked down to Dawes limit, when seeing permits.
The comfortable conditions had prompted someone to start playing a guitar. I didn't object, but I would have preferred silence. I wondered where the raccoon was: Just because I do not consider guitars edible does not mean that more developed palates will refuse them.
I took a gee-whiz look at NGC 7009, the Saturn Nebula, at 244x. I was able to see the "ansae" of this blueish planetary, which give it the appearance of Saturn with the rings nearly edge on. The oval central disc showed some inhomogeneity of brightness, but I could not detect the central star. I located a nearby NGC galaxy, NGC 7010, then noticed a much more interesting object on the same page of Millennium, the Aquarius Dwarf Galaxy, a tiny object that seems to be just outside the local group of galaxies. Navigating over to it, I found a faint, round glow, just visible with averted vision, perhaps an arc minute in diameter, with a star of roughly magnitude 13 south adjoining. A few days later, I downloaded an image from the Digitized Sky Survey and confirmed my detection.
I finished up the evening with a look at the Helix Nebula; with my Orion UltraBlock filter held in front of my eye, like a big monocle, I could make out nearly two complete turns of the "helix" at 98x.
I started taking down my equipment at about 2 AM. With it all packed, I strolled around the parking lot, chatting with the handful of observers who were still active. One of them asked me if I had brought a telescope.
I told you Harvey was an invisible pooka.