A comet in the clover, Sunday night at Lake Sonoma

by Jane Houston Jones

After observing the planerts and moon the previous seven straight nights, three times on San Francisco sidewalks, 5 times on our back deck, and once with the Sonoma County Young Astronomers club, all in urban or suburban settings, we decided a little dark sky observing was in order. We checked the coordinates for comet Ikeya-Zhang, and headed for Lake Sonoma with our 9x63 Celestron binos, our compact 17.5 and 14.5 inch truss-tubed Litebox reflectors and a Short Tube 80 to be used as a finder on the big dob.

We arrived at Lake Sonoma just at sunset. We decided to check and see if the upper lot, Lone Rock Flat, was open, as it is higher with better horizons. It was open and the entire area was covered in green clover with tiny flowers. It smelt like spring, and walking on clover is nice on the feet. No dust, either! We drove to the far end of the football field sized lot, and parked next to the picnic tables, and set up our telescopes on the blanket of clover.

We had taken the mirrrors out of their mirror cells during the afternoon and washed them, and we expected a little more time would be needed to collimate the telescopes last night. Surprizingly both were nearly dead-on aligned, needing less than 30 seconds of tweaking the collimation bolts on each telescope for perfect alignment. I love it when that happens!

We brought my nephew Aaron with us, and he was busy sketching the silhouette of our two dobs in the dusk with a piece of charcoal on my sketch pad, then sketching the hills in twilight, and basically being a six year old in a field of clover. Once the telescopes were set up we sat down to enjoy the unfolding of the night, the pink horizons and the to see the first stars to appear in the winter sky.

Soon Mojo noticed Venus just a few degrees above the horizon, so we quickly pointed the telescopes at all 5 visible planets, Venus, Earth, Mars, Saturn and Jupiter. Then Aaron took the helm of the 17.5 incher and standing on a ladder, aimed first the telrad, and then eased M42 into the eyepiece. He has his own f/5 6 inch reflector and has become quite the observer since Christmas, watching Eurpoa's occultation a few nights ago, and making up and drawing constellations.

Then we went for Comet C/2002 C1, Ikeya-Zhang, which was set in the glare of the Zodiacal Light in Pisces last night. It was just an amazing view in the darkening sky. The comet, for those of you who have not seen it yet, is really lovely, with a very long tail, perhaps 2 - 3 degrees long in a dark sky. It totally filled the field of view in my Orion Short Tube 80 with a 25mm eyepiece in it. We put the 31 Nagler in the focuser of my big 17.5 f/4.5 reflector, aimed low, and the comet filled most of that field too.

About this time Aaron's mom and dad arrived to join us, and we discovered another observer had set up at the very front of the lot. Aaron and I walked over to say hello and we soon met Michael Gold from the PAS club, up from San Francisco. It didn't take much persuasion for Michael to join us for a look at the comet, and to see for his first time, the Zodiacal Light.

We watched this comet for over a half hour in both big scopes and the finders, watching its slow movement against the background stars. It is magnitude 5 right now, easily visible in binos and it reaches perihelion March 18 when it will be 45.6 million miles from the sun. Look now while you have the chance!

Next on the agenda was some Messier Marathon practice. We'll be driving to Texas this weekend to pick up a new telescope and will observe the Messiers from Fort Davis, and other points southwest on our drive back through our new toy. First up was M74 in Cetus. Low and practically lost in the glare from the Zodiacal Light, we still grabbed it. Well Mojo did, in his 14.5, and I just looked. We triede to remember which of the stars was the Supernova from a few weeks ago, but couldn't exactly remember, but we think we saw it.

We both practiced some Messiers we haven't looked at for a while. I found at M78 in Orion, and M79 in Lepus, as I wanted to view some objects in that neighborhood with our two matching sets of new-to-us used Zeiss Abbe Orthos.

I wanted to compare the views of the Horsehead nebula in different eyepieces. The ZAO 16 against my favorite old 16mm Nagler was one test. In the ZAO with H-beta filter, the field was dark and the horshead "sock" was very black, a real contrasty view in my 17.5 incher. Using the 16mm Nagler 2, it was also easy to spot but the background was not as dark, the sock less black, with some scattered light in the eyepiece field. The 82 degree apparant field of view in the Nagler is so useful, tho', that it remains one of my favorite eyepieces, especially for deep sky objects.

Another comparison was between the 10 Radian and the 10 ZAO. These Radians are really great, with 60 degree fov. The ZAO's have an apparant field of view of 45 degrees, excellent for planetary and lunar observing, but I do like the wider field of the Naglers for deep sky viewing. But with more practice, I think I'll use the ZAOS for high power views of faint fuzzies. We did trials on Jupiter and Saturn through the 14.5 incher, and on NGC 2359, the tadpole nebula, and on parts of the Rosette, NGC 2337 - 39 with different eyepeices and the O111 filter. The transparency and seeing were so awesome we regretted not bringing the 4 and 6 Radians to do more high power comparisons.

At about 10:00 p.m. we both pooped out, packed up and headed home, stopping at a great truck stop all night diner in Petaluma. It's shaping up to be another great night up here in the North Bay, and since the car is already packed with dobs, we'll be going back to Lake Sonoma tonight for more view of the comets in the clover and more

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