by Jay Reynolds Freeman
Scattered high clouds crossed the San Francisco Bay area during the day on 24 March, 2000, but I decided to head south after work, and pick an observing site based on what the weather looked like. Lots of blue to the south and west led me to Fremont Peak, in the hills above Salinas. I was the only occupant of the southwest lot, but my faith was rewarded -- by the time I finished setting up my Celestron 14, the sky was clear.
It was chill and damp. The temperature started at 10 C, with relative humidity at about 60 percent, but as the temperature dropped toward zero, the relative humidity climbed into the 90s. I could see fog developing over the coastal plain to the west, and knew that just a little wind would bring it upslope to ruin my evening. Yet instead of a remnant of winter, the weather pattern hinted more of summer to come: An hour or two into the evening, a mild inversion began to form. The temperature rose a degree or two, and the relative humidity dropped. There wasn't much water in the air, anyway -- cold air won't hold a lot. I had dew on the exposed dark cushion of my observing chair, but none on my car roof or chart table, and my Kendrick anti-dewing system kept the C-14's corrector dry, even though I did not bother to put the dew cap on the tube.
Before the fog grew dense, I took a look at some sights in Orion. M42 was magnificient at 98x, showing green around the Trapezium and reddish purple in the long "wings" that extend therefrom in nearly opposite directions. I could see NGC 2024 and 2023, but even though I could locate the field exactly, I could not spot the Horsehead, even with an Orion Ultrablock filter. I was aware of sky brightness from Salinas as I looked, and did not think to try again later, after the fog had thickened. I did find some other faint nebulae central Orion, including IC 423, IC 426, and IC 435.
Then I continued with my program of chasing obscure galactic clusters in the southern Milky Way, that I mentioned in a recent posting. That went well for a while, but then a transiting wave of moisture, in the form of patches of broken cirrus cloud, added some excitement. These conditions do not stop visual observing, they merely slow it down, for there are sufficient clear lanes between the cirrus strips to see through, yet star hopping gains a new challenge when the stars periodically come and go. After a while, the cirrus thickened enough to be bothersome, but the northeastern sky was still clear, so it was time to look at something else.
I hadn't been through the Coma galaxy cluster for a while, so I opened the relevant page of the Millennium atlas and waded in. For the C-14, this is a region where there are more galaxies than stars -- more than two score in a few square degrees, with almost as many outliers, plotted on the chart, and the C-14 goes deeper still, so it is possible to get confused by galaxies which are not charted. I logged some 70 objects in an hour and a half, even though I had to take a break while the same wave of moisture crossed the area. Several of the galaxies appear as little groups -- the one comprising NGC 4871, 4872, 4873 and 4874, was particularly appealing.
The Moon rose a few minutes past 11 PM, and I took down the telescope nd drove home. What a shame that no one else was there to share such a good night, the more so since there have been so few of them so far this year.