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by Jay Reynolds Freeman
Friday, June 11, 1999, found Fremont Peak State Park, California, almost empty of telescopes when I drove up past the Ranger's house with Harvey, my Celestron 14, in early evening. Only a few more observers showed up later. What a pity, for it was a quite good night.
I took a brief look at Mars in relatively poor seeing, then pulled out my Royal Astronomical Society of Canada Observer's Handbook, to use its detailed chart to chase down Pluto. This most distant and faint of the Sun's traditional family of planets was bright enough to be an easy shot for the big Celestron, and the RASC chart had enough stars to make possible a good guess as to which otherwise undistinguished point of light was the planet. I lucked out; two views at 98x and 244x, a few hours apart, showed that the target I had thought most probable had in fact moved in the interim. I had only looked at Pluto once before.
My main program for the night, however, was working down my cats and dogs list of deep-sky objects, and several Abell clusters of galaxies were well placed. These objects cover a wide range in difficulty; for Harvey, from obvious to impossible. The night's work spanned nearly that entire domain.
Abell 1367, sometimes known as the Leo I cluster, is centered at roughly 11:44 +20 (epoch 2000). This relatively nearby and relatively prominent grouping includes at least twenty galaxies bright enough to have an NGC number, plus several more with UGC or IC entries. A magnification of 98x was enough to allow me to find most of the galaxies that Millennium Star Atlas plots in this area, but it took 244x clearly to identify some of the ones in the central part of the field. There were lots more besides.
Abell 1377, near 11:47 +55, was identifiable as what another observer termed "an active field" -- lots of tenuous lumpy structure, hovering at the edge of detectability at 98x. I reviewed a digitized sky survey plate after the evening was over -- what we were looking at was indeed the heart of the cluster, but what we were seeing was probably better described as unresolved little subgroups of galaxies, giving a sense of granularity or texture the same way that unresolved groups of stars do for globular clusters, only at a larger angular scale and at rather lower contrast. There were a number of NGC galaxies nearby, but none of them seem to be actual cluster members.
Abell 1318, near 11:36 +55, is not as dense as Abell 1377, but the individual galaxies, on a digitized sky survey plate again, seem to be of roughly the same angular size. At 98x, I saw some fuzz at the nominal position of the cluster, plus a few NGC galaxies in the same general area. I don't think NGC 3733 is a cluster member -- or if it is, it is one of those unusual huge, low-surface-brightness spirals. NGC 3737 might be, though.
Abell 1314, near 11:35 +49, seems to have slightly brighter galaxies than either 1377 or 1318, but is still less dense. UGC 6541 is the brightest in the area, and at 98x, I spotted three or four more for which I have no identification.
Abell 1225, near 11:21 +54, and Abell 1270, near 11:29 +54, both showed merely as almost indistinguishable patches of haze in the C-14 at 98x, with no identifiable galaxies to be seen in either one. The latter cluster is rather more concentrated than the former. Detections such as these are pushing the limits of the telescope, but fuzz I did see.
High cirrus encroached on Fremont Peak not long past midnight, but before it had completely crossed the sky, I had a wonderful view of the Veil Nebula in a newly-commissioned 10-inch Dobson, whose proud owner had made the primary himself. At 43x, with a Lumicon OIII filter, I was able to see as much of the nebula as I have ever seen plotted on any chart, including the wispy stuff inside the main interrupted ring. This owner can be very proud of his handiwork.