Make your own free website on Tripod.com

Observation Report
Lake Sonoma, Monday, February 26, 2001

by: Shneor Sherman

After checking Starcast, satellite photos and a couple of forecasts, I concluded that Monday night was most viable for an observing session at Lake Sonoma, and that it was probable that Tuesday night would be no better, and likely not as good for viewing. I contacted Gregg B. and we agreed to meet at the Arco off the North Texas exit on I-80 at 7:15. I checked the forecast a few more times before leaving - still looked ok. But as we drive into Sonoma County, the skies were still overcast, and remained so until we hit Dry Creek Road. When we got to Gray Pine Flat at Lake Sonoma (a trip made 8 miles shorter by Gregg's suggestion of using Highway 12 instead of 37) the East and South were still cloudy, and only the West and North-West were clear. But there was quite a bit of moisture up there anyway...

We arrived around 9:20 and were set up sometime before 10. Got in a quck peek at Jupiter while aligning my finder, but conditions (mirror not yet in thermal equilibrium) were pretty poor. Saw three satellites and a couple of bands, not very good for an 18", then again just 68x. The sky was not uniform during the night, as clouds and moisture moved southward across the Northern and Eastern sky. Conditions varied considerably.

One item I had wanted to check out Monday night was a new 9mm UO Orthoscopic, which sells for a ludicrous price of $59 or so. I soon tested this marvelous eyepiece on a number of deep-sky objects. But I began with Ursa Major (which I returned to several times during the night as it rose ever-higher). M109 was well-defined at 68x, the core very clear and with hints of spiral structure. It looked good with my 13mm Nagler, with some structure, but the view with the 9mm was the best, with clear structure revealed in the hazy oval surrounding the core.

I viewed M51 several times during the night, the last around 1 a.m. M51 was quite high, and the view with my 9 mm ortho was like a photograph, with the huge spiral arms of M51 filling the 12 arcminute field. It simply blew my 13mm Nag away. Gregg borrowed the eyepiece, and it blew his 12nn Nagler away on his 25". This eyepiece just has excellent light transmission and contrast, but of course, a relatively small field of view.

(As I did not record what I saw except in memory, the following is not necessarily in chronological order.)

Leo rose shortly after we arrived, and by 1 a.m., it was at it's highest point in the sky. Due to some clouds at the time I viewed, M65 and M66 looked dimmer than expected. Repeated attempts to find Copeland's Septet again failed. I suspect that this was due to the moisture, which in general limited visibility for me to magnitude 14 or thereabouts at best. N3607, N3608 and N3605 were a nice group in Leo's tail but appeared dimmer than they should be, viewed with a 13mm Nag. A pretty group of 4 galaxies between Adhafera and Algeiba in Leo are N3193, N3190, N3187 and N3185. N3187 was barely visible. Another pretty group is near Spica, a group with 6 galaxies in the field. There is a line of galaxies, N5070, N5072, N5077, N5079 and N5076, with N5088 off to one side. These were also viewed with a 13mm Nagler. Of course, I couldn't pass up viewing M81 and M82. Quite a bit of detail, in M82 including vertical dust lanes were visible in my 9mm (yielding about 228x). But M97, thw Owl Nevbula was quite detailed with the 9mm and a UHC filter, and the central star popped in and out of view. The "eyes" were clearly visible.

I viewed a number of galaxies in the bowl of the dipper, but could only see N3992 out of a cluster of 8 galaxies. Also had an excellent view of the Sombrero, M104, in the 9mm, with the dust lane clearly defined.

Some first sights of the season were M13, M92 and M57, none of which looked too good because of coulds/moisture and low altitude. I finished the night with a tour of bright galaxies in Virgo. All in all this was a very enjoyable night, after a month of difficult weather.

I very much hope we will have good skies somewhere accessible in March. This is such a great season for Leo and Virgo, which somehow do not seem to be visible as much as they should be, probably because HGO has such a poor southern and western sky for the most part.

Back To Menu