by Shneor Sherman
In any case, the evening began very well, with skies at least mag 6.5. Even with the thin crescent moon, it was possible to observe various DSOs although the quality was dimninished (for example, no color was visible in M42). The moon set a bit after 9 p.m., and the band of moisture visible in satellite photos in the upper atmosphere reduced transparency a bit and reduced the limiting magnitude to 6. Seeing, which had been excellent (I was able to view objects with good steadiness at about 700x early on) also deteriorated a bit, to merely average a bit later. Nonetheless, it was quite dry and not a trace of dew appeared all night. There was a pesky breeze gusting to about 5 miles per hour which also affected seeing although there were numerous quiet times. It also became quite cold, probably in the high thirties, and stayed that way all night.
I especially like the spring sky because it's just chock-full of galaxies in groups and clusters, and there never seems to be enough time to view as many of these as I would like. I had excellent opportunities Saturday night at IHOP.
I arrived at 4 p.m. and left at 4:30 a.m. Sunday morning.
| Equipment | 22" f/4 Sayre Monocular+Osypowski Equatorial Platform
30mm Widescan II+Visual Paracorr 13mm Nagler Type 1 6mm Adorama Ultraview 2" 2X Nagler Powermate Denkmeier Standard Binoviewer+2" OCS Rini 30mm Wideangle (binoviewer) Eyepieces DGM Optics NPB Nebular Filter Burgess 25x100 Binoculars+T&T Parallelogram Mount |
|---|
Observations are not necessarily presented in chronological order.
Early on I had excellent views of the moon in binoculars and using my Denks. In the 25x100s, great lunar detail was visible not only on the sunlight crescent, but on the vast majority of the visible lunar surface illumnated by earthshine. In the binoculars and the Denks the three-dimentionsl feeling was greatly enhanced, and I suspect more detail was perceptible than is possible using the same magnification with only one eye. It was particularly enjoyable to see the sunlight advance across Mare Crisium while observing. Thanks to Mike G. (as best I can recall), who pointed out that Mercury was visible, I had a quick glimpse of that elusive planet, although it was so low and over Sacramento to boot, that it appeared to be boiling, although it was possible to discern that a tad over half the disk was illuminated. The view of M42 was unimpressive until after moonset. I did view some galaxies in Leo and elsewhere prior to moonset, but the view uas unremarkable at best despite the minimally illuminated moon.
Leo is notable for triplets of bright galaxies. There are at least 5 of these, the most impressive being M65-M66-NGC3628. I had several excellent views of this group using my Widescan II. Dust lanes were clearly visible in N3628, and structure in both M65 and M66. This group was also impressive in the 25x100s. I had a good view of another triple group consisting of NGC 3605, 3607, and 3608, which looked good in my 13 Nagler, with the galaxies almost in line. Another nice triple - although to be honest there's a fourth galaxy in a wide field, is NGC 3681, 3684 and 3686 (with 3691 also in the field). Then there are M105, N3389 and N3384, a nice compact group. Also, there are N3186, 3190 and 3193, between Adhalera and Algeiba also known as Hickson 44, if memory serves). Viewing these bright galaxies was a lot of fun, but I had a couple of additional targets in Leo.
One of these was Copeland's Septet, a vey compact group of 8 galaxies. I had an excellent view of these four or five years ago at Fiddletown, in my 18", on a superb viewing night. While the group was visible using my 6mm (about 375x), it was quite dim, and required averted vision to see all 8 galaxies. Another target in Leo was Abell 1367. There were at least 8 galaxies visible in the field, several visible only using averted vision, and as Randy Mueller remarked, with many different shapes.
I viewed Markarian's Chain a number of times during the evening as well as a number of nearby galaxies, including N4567 and 4568 (the Siamese Twins). This was also a fine sight in the 25x100s.
Some of my favorite objects seen during the evening were NGC 4565, NGC2371/2 (the Peanut Nebula) seen at 375x, with the central star clearly visible between the "disks", Thor's Helmet (seen using the Nebular Filter) and a number of views of M42. After moonset, the pink and green colors of the nebulosity were clearly visible and were especially impressive in the Denks. With the nebular filter, a greatly extended area of nebulosity was visible. This was also a fine sight in the 25x100s. M3, M4 and M13 were impressive in the Denks, which provided a 3-D feel to the images. I also had nice binoviews of M52 and M101, when M52 was at the zenith. I also briefly viewed M57.
After 2:30 a.m., I spent about 45 minutes searching for Centaurus A and the Centaurus Cluster, as a number of stars in Centaurus were easily visible in the more easterly part of that constellation. However, I was unsuccessful, possibly due to a bit of cloudiness toward the south-southwest horizon. I was also unable to find Omega Centauri with the 25x100s, probably because the trees interfere with the southern horizon's lowest two degrees.
Posted on tac-sac Mar 13, 2005 19:44:04 PT
Converted by report.pm 1.2 Mar 14, 2005 19:26:23 PT