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by Jay Reynolds Freeman
I took my Celestron 14 to Fremont Peak State (California) Park twice on Fourth of July weekend. Perhaps because of the early Moon rise and the holiday, few people were there either evening.
Weather threatened Saturday -- the coastal marine layer was thick and tall, and a strong sea breeze at dusk brought it inland. Cloud tops were near the peak elevation, and wisps of vapor occasionally curled around the ridge crest or wafted over roads. Yet a developing inversion won. Relative humidity began at 50 percent, climbed after sunset, and then declined. The sky stayed clear. I looked at the evening's planets in so-so seeing, then spent most of the 2.5 hour interval of darkness chasing Hickson groups and other galaxies. Tough-object highlight of the evening was Palomar 5, a low surface brightness globular cluster located a few degrees from Messier 5. The Palomar object is lots fainter. I could just barely see it in a 40 mm Vernonscope Erfle eyepiece (98x) and in a 16 mm Brandon (244x).
Next night, the wind slackened, the seeing improved, and the marine layer stayed off shore. Several of us used binoculars and the naked eye to watch fireworks on the coastal plain. Turning to the telescope, at 244x, I got a decent separation of all four components of nu Sco -- on Saturday I had only been able to separate the wider pair. I split Antares, too -- which is not challenging in absolute terms, yet is often difficult for larger apertures, so close to the horizon. Higher up, I had a view of epsilon Lyra that reminded me that at times, my C-14 has run diffraction-limited.
As twilight deepened, I spotted Mercury low in the west, and turned to it. At 98x, its half phase was clearly visible, but seeing deterred higher magnification. At 98x, Venus was a lovely bright crescent, and to my eye, the brightness distribution along the terminator was not homogeneous; there were some dark areas. Mars revealed some detail at 98x, and 244x showed a bit more.
I reviewed Seyfert's Sextet, also known as Hickson 79, in Serpens. At 244x, with patience, I convinced myself that I was seeing lumpy darkness at the positions of all six of its components, which comprise five separate galaxies and one starry plume, off one of them, large enough to have its own identification. These are tough objects, though. My observations were at the limit of my telescope and ability.
Next I sought Hickson 80, up in Draco, but could find no trace of it at either magnification. I am confident I had the field correct. Can anyone report an observation of this group?
Hickson 82, in Hercules, was easier. At 244x, I spotted NGC 6161, 6162, and 6163, as plotted on Millennium Star Atlas, and was able to show them to others. There is a fourth galaxy, but I did not know where to look for it, and could not detect it without a position.
Then I went after some little-known globular clusters. I found Terzan 1, 3, 4, and 12, plus IC 1257 and Haute Province 1. Some of the Terzan globulars had surface brightness so low they disappeared when I increased magnification from 98x to 244x.
On these evenings, I was using a different finding technique than I usually do. The mount -- a Losmandy G-11 -- has pretty good mechanical setting circles (that's "mechanical" as opposed to "digital"). Inasmuch as my "cats and dogs" observing list has right ascension and declination for each object, I decided to try to use the circles to find things.
It took but a moment to calibrate the declination circle more or less permanently, but I had to keep readjusting the one for right ascension: Even though it is a "driven" circle, which will read the same as long as you track and observe the same object, nevertheless, it is driven not only by normal tracking but also by slewing and fine setting. One of my habits is to wander around in the vicinity of whatever I am looking at, seeking other objects that are on my charts, using the Losmandy's motors. That messes up the right ascension setting. But the circle is easily adjusted, so it is no big deal to set things right.
Yet there was a more serious problem with the setting circles. Verniers or not, I had difficulty adjusting them to much better than a degree. Carrying a small mirror might have helped, for one problem with the verniers was that I was often looking at them obliquely -- not the best thing for lining up marks on a dial. Even a few tenths of a degree off was too much, particularly for the narrow field of the 244x eyepiece. Thus I would have to use the finder to fine-tune alignment, after I had used the circles to get to approximately the right place. Unhappily, even using an atlas that showed all the stars my finder did, I found it harder to identify star patterns in a finder field that I came to "blind", than when I had worked my way out from a known pattern, star-hopping from shape to recognizable shape.
Thus although using the circles made coarse slewing quick and easy, I believe I lost so much time in the final stages of zeroing in, that the whole process was slower than straight star-hopping. I may try it some more though, for the circles were indeed straightforward to operate. Perhaps I can find a way to make them useful, but it appears to me that I would need accuracy of perhaps an arc minute to make do completely without the finder, and I am probably not going to get that from conventional setting circles that will fit on a Losmandy G-11.
As the observing session drew to a close, I looked at some favorite showpiece objects. One of us had spotted the central star of M27 in a C-11, so I turned the C-14 toward it, and had a steady view of the star at 244x. I looked at M17 at the same magnification, and was rewarded with rich detail in the brighter parts of the nebula -- it put me in mind of ruffles in the feathers of the Swan's neck. I put in an Orion UltraBlock filter to look at M16 at 98x, and saw plenty of nebulosity and a glimpse of the "Star Queen" dark nebula (opinions differ on what part of M16 is the "Star Queen"), but not as good a view as I have seen in the past, probably because the Moon was about to rise.
Several people were chasing planets, so I pulled out my Royal Astronomical Society of Canada Observer's Handbook, paged through to the planetary charts, and found Uranus and Neptune. Both showed lovely colored discs at 244x, Uranus misty green and Neptune pale blue. At least two of Uranus's moons were visible. Finally, I dropped to 98x and located Pluto, in a sky awash with light from the just-risen Moon. A neighbor with a large Dobson had found it as well. It was gratifying that we agreed on its position, and as further reassurance, we gave each other the secret Plutocrat salute, reserved only for those who have found and identified Pluto all by themselves. The Fraternal and Luminous Order of Plutocrats (FLOP) initiated a new member that night, for with coaching, a relative newcomer worked her way from Zeta Ophiuchi out to that not so luminous planet.
On the way home, I spotted Jupiter and Saturn clearing the hills to the east, and with a glance at the Earth below, I completed a tour of all nine planets between dusk and dawn. I am sure that I don't have to remind you, that you are not allowed to do deep-sky observing until you have looked at all of the traditional planets. What's more, once you have done that, remember also, that you are not allowed to observe external galaxies until you have seen all the NGC objects in the Milky Way... :-)