Adventures with a NexStar 5

I recently (that was August 2000) got my hands on a NexStar 5 and took it along on a vacation to the White Mountains of Arizona. While not in the same class as hauling a big Dob up to Hale Pohaku (hey, I was impressed by that report on sci.astro), my experiences might be of interest to a few folks out there.

On a visit to Tucson about a month ago (my last observing run at Kitt Peak having been beautifully timed for the start of monsoon season, resulting in some of my personal best lightning pictures), I looked around at a couple of telescope shops to compare the Celestron and Meade 5" products. The folks at both Starizona and Stellar Visions were more than helpful in demonstrating both side-by-side. When I came back a few weeks later for a long-planned family vacation, the choice on where to by was strictly conditioned by which place had a secondhand NexStar that had come in as a trade-in. I picked the NexStar over the Meade because it fits my needs a bit more closely. The faster f/ratio (as if f/10 were "fast") makes deep-sky work a bit easier than f/15, and the NexStar folds into a rather more compact unit for transport. Besides, even if it's seldom used, any right-angle finder is an abomination upon the land. (I hope that my grumpiness over our dept. once having to wait 22 months to get a Pictor CCD camera delivered didn't enter into it; we do use 10- and 16-inch Meade Newtonians for classes). In construction, the single metal support arm seems more steady than the plastic fork. I was reasonably impressed with the usability aspects of the system, such as the star pointer and intuitive alignment procedure.

Off we went for five nights at a cabin in Greer, located in the White Mountains of Arizona between Springerville and the Sunrise ski area (elevation about 9000 feet). So far so good, except that the visit started at full moon, and the summer monsoon pattern extends this far north with local modifications. The typical daily weather pattern was clouds building up during the day, often with rain or thunderstorms near dusk, clearing well after midnight (yeah, after moonrise). When it was clear, it was quite dark, with essentially no strategic light pollution and spotty tactical sources (a couple of street or cabin lights that I couldn't miss while still gettinng clean horizons north and south and not having to go too far).

Night 1. Weather clears off, decide to have a shot even with the full Moon. The visual limiting magnitude, based on Ursa Minor, is about 5.0. Still better than most moonless nights at home. At 50x (which is what I used almost exclusively, though I did bring a 9mm eyepiece along to try a few higher-power views), stars showed up in M13 and M22. It was surprising how prominent M51 and its companion appeared (or maybe I'm just accustomed to rotten skies). This was a chance to see how choice of alignment stars and care in centering them play out in pointing accuracy. After aligning on Arcturus and Altair, there was a very consistent pointing offset of more than 0.5 degree across the NW sky, while objects to the south were right as advertised. No chance to look for comet LINEAR, since it was below the treetops once the skies cleared.

Night 2 (2 nights later). There were about 1.5 hours usable this time. To catch it at all, I started with comet LINEAR, which looked like a miniature of Bennett in 1970, with parabolic outline to the coma and tail (of which I saw a bit more than 1/2 degree, within 10 degrees of the horizon). At first I thought the sidereal tracking was bad this low in the sky, until I remembered just how fast the comet's apparent motion was. On to deep-sky objects. The pointing was better overall tonight, even with the same setup stars (maybe I was more careful centering the stars or something). The Lagoon Nebula was nice, with plenty of nebulosity. I caught NGC 6231 just in time, with treetops in the field of view (this is one that will join my list of public-night views). In a quick look at the Virgo Cluster, the central galaxy M87 was pleasantly big and fuzzy. To its north, the edge-on spiral NGC 4565 showed as a faint but well-defined splinter of light. M101 has always been a problem for my eyes - never have found it with my 10" Coulter from my house in Tuscaloosa, despite star-hopping so I knew it was in the field. My only previous sighting used 12x80 binoculars from Kitt Peak. But it was very obvious in the Nexstar, as a round glow with almost no central condensation. I caught M81 and M82 in the same field below the Pole (score one for alt-az mounts; lots of equatorials would barf at that). Added M4 to well-resolved globulars; M80 next door is quite a contrast, a cometlike but unresolved glow. Finished off with the Dumbbell and Ring nebulae (well-defined but still tiny at 50x) before moonrise and increasing clouds sent me off to bed.

Night 3. Chasing holes in cloud cover the whole time, so I learned some interesting things about alignment and its improvement. The evening started with a Mir pass at magnitude 1.3, and a magnitude -8 flare from Iridium 80 flare nicely backlighting a cloud in front of the Cygnus Milky Way for several onlookers. I set up on a dirt road between the cabins, to get a level place for the tripod. The only car to pass thoughtfully dimmed to parking lights when they saw what I was doing (and the driver even remarked on what a nice dark place it was). I concentrated on the southern Milky Way (maybe because that's where it was easiest to tell whether a cloud was in the way or not). Some individual stars showed up in M5, but not M9 or M14. The Trifid stars were obvious, but not the nebula itself. One odd point is that it kept looking for M10 below the horizon, as if it had dropped the leading zero from the declination (will probably check this out the next clear night we get around here). In a fit of laziness, I spent a few minutes running the table of Sagittarius Messier clusters. The cores of globular clusters were especially interesting, since M54 and M70 have rather prominent bright cores and M60 doesn't. I'll add M22 to my public-night showpiece list. No comet tonight, with all those clouds to the north. I turned around to examine M31 and M32 as moonlight approached, then watched moonrise over a nearby ridge. The seeing was no great shakes, but watching the pines and occasional bats silhouetted against the visibly moving Moon was worth waiting for.

I did catch the comet once more from Tucson on July 22, with the nucleus still bright and starlike (little knowing what a short-lived sight that would be).

This was all on a single set of AA batteries, which surprised me a bit since the folks at both telescope stores said that batteries tended not to last as long as Celestron says. Go figure.

I can verify that the Nexstar, folded straight down, will fit in a duffle bag under an airplane seat. Imagine, if you will, the faces of the X-ray operators in Phoenix airport who were determined not to ask...


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