by Jay Reynolds Freeman
Saturday, 17 April brought the first truly good dark-sky weekend to central California in over three months, so I eagerly packed Harvey, my Celestron 14, and headed for Fremont Peak. Conditions were less crowded than I had expected -- perhaps local observers did not believe that the weather had actually improved.
I long ago did a Messier survey with the big Schmidt-Cassegrain, but on recommissioning it last summer, I decided to do a repeat. It is always wonderful to see how much detail a large aperture brings out in these old friends. The view of M104, for example, was truly spectacular -- at 98x, the galaxy showed a bright nucleus, lenticular bulge and dark edge lane, with bright matter clearly visible on both sides of the lane. M68 showed considerable resolution at the same aperture. M65 and M66 showed bright nuclei and considerable differences in detail, in sharp contrast with the long, dark-banded streak of neighbor NGC 3628.
Part of my program for the evening was finding faint galaxies near the bright Messier ones. The region from M61 to M49 is a wonderful area for this kind of hunting. With Millennium Star Atlas handy, I did a zig-zag star-hop from the former to the latter, and logged some fifty galaxies along the way.
An hour or so before midnight, Mars cleared a nearby tree. Seeing was only fair, but there were enough moments of clarity to use a 12 mm Brandon eyepiece, for 326x, with good effect. I did try more, but my 8 mm Brandon (489x) was too much, whereas the 16 mm (244x) did not allow easy access to all detail present.
Syrtis Major was crossing the central meridian. When seeing settled, I could see hints of irregularity to its border -- the word that came to mind was "scalloping". Its northern tip appeared at times notched, like a gunsight. Bright Hellas lay to the south, at first fooling many of us into thinking it a polar cap. At the other end of the planet, the true northern polar cap was tiny, and I could not quite decide for sure whether there was any darkening immediately adjacent to it. The patchy dark areas of Nilosyrtis and Boreosyrtis merged into one big blur when the seeing was not good, but in better moments separated into several shadows whose precise shapes I could never hold for long enough to detect. Bright white areas lay at both limbs, near the equator: I could not tell for sure whether they were surface features or meteorology. Sabaeus Sinus was well-placed and easy, and Meridiani Sinus had not quite emerged into visibility.
I had set up next to a late-model Astro-Physics 155 mm f/7 refractor, whose owner was also studiously observing Mars. Everyone always wants to know how Harvey stacks up compared to the high-end refractors on planetary detail, and half the fun is that it is almost impossible to get a definitive answer: My friend was using a Zeiss binoviewer with eyepieces that I forgot to identify, at about 200x, which he thought best for conditions. I observed through his telescope for a couple of minutes, and through mine for perhaps half an hour. The view through the refractor was steadier -- no surprise considering the smaller aperture and lower magnification -- but to my eye, the views I got in my brief use of the Astro-Physics did not show as much detail as I saw in my longer session with Harvey. The difference, however, was not in proportion to the apertures.
Yet there are several caveats: First, there is an intrinsic bias created by the different lengths of observing time in the presence of varying seeing -- the greater time I spent with Harvey allowed me a better chance to see Mars with the best seeing the night had to offer, than did my few minutes with the refractor. Second, the seeing was not good enough for either telescope to work at its best. Third, binoviewers generally do not "work" for me -- I find that I get a better view by ignoring what one eye sees and using only the other. (Some of that problem may stem from poor design: Few binoviewers allow separate focusing for the observer's two eyes. Zeiss is as inept as the rest -- their engineers should take lessons from Tasco.)
Anyhow, Harvey was certainly doing well, and considering that I bought my C-14 as a deep-sky telescope, and that it is a lot cheaper than a six-inch Astro-Physics, I am well pleased. The Astro-Physics owner likes his telescope, too, so everyone is happy.