Shadows in the Dust

Observing at Henry Coe SP, 1996 Aug 17

Last night (1996 Aug 17/18) the San Jose Astronomical Association had its regular monthly dark sky party at Henry Coe State Park just south of San Jose CA. I brought my 12" Meade LX200...

I got there just after sunset and began to set up. Right away I hear off in the distance: "Is that an LX200? Yeah, it looks like an LX200. ..." For the next half hour or so I was making slow progess setting up in between talking to the newbies and apologizing for not being able (yet) to show them anything. But what the heck, if I wanted to be alone and bag 100 objects/hour I could have gone up on Thursday night :-)

The site where we set up is being all torn up for some construction (someone said a new house for the ranger). It was incredibly dusty. I hate setting up on dirt and this was worse than usual. I had been at the same site a couple months back and it was OK; dirt but hard-packed. Last night was really yucky, a layer of dust covered the whole area. By the time I got home my tripod, observing chair and accessory power box were all covered with fine dust. There was even some in my computer. My optical surfaces seem to have survived, at least. Maybe it will be better when the construction is done. Meanwhile, I'll stick with the parking lot near the campground instead.

Shortly the distant voices started saying: "The Red Spot should be visible about now. ... Yeah, there it is!". So I decided once again to skip my planned experiments with alignment methods and quickly got my scope pointed at the King of Planets. "Gee, the seeing's pretty good tonight!", I thought, "I'll try jacking up the power." I was able to hold a reasonably clear image at 600x, though I thought it really looked better at 330x. But the GRS was very clearly visible with part of the belt on either side. I thought I could see a few white spots in the SEB and there were definite dark spots in the edge of the NEB, but no festoons that I could see.

There was a family there with a brand new LX50 which had a very strange tripod that they called "a Tuthill" (I guess they bought it from Roger W. Tuthill Co.). It had two long wooden legs and one short adjustable aluminum one. It managed to get the scope approximately polar aligned by simply scooting the legs around to the right azimuth and adjusting the short leg for latitude. Nice idea, but I wouldn't want to rely on it for photography -- I doubt it would be possible to get perfectly aligned. But its probably find for visual work and appeared to be just as easy to set up as an LX200 in altaz mode (and a whole lot cheaper!).

A first for me was seeing real differences between the Galilean moons. Callisto looked definitely darker, Ganymede was clearly larger and Europa clearly smaller. Next time the seeing is that good, I'll try identifying them without first checking my computer :-) Based on what I saw, it should be possible.

Saturn was sporting its usual retinue of faint moons plus Titan. My computer's batteries had died so I'm not quite sure which was which but at least 5 were visible. Jim Van Nuland and I were unsure about Mimas, it would seemingly appear for a moment and then hide for a while. The seeing had deteriorated badly since earlier in the evening but Saturn is always a treat :-)

M31 was amazing. For the first time, I was able to see clearly some dark lanes. And I was able to trace the outer reaches of the disk out much farther than I previously had. M32 and "M110" were very plain, visible even with 8x56 binoculars.

M33 was easy, too. I was able (again, for the first time for me) to see structure in it, too. I suspect it would have been visible naked eye for someone with better eyesight. Too bad the newbies and the younger club members had gone home by then :-)

At about 4am Venus appeared. Its so amazingly bright when up in a dark sky! It makes giant Jupiter look pale. As I was sitting talking to Jim, I though I could see shadows. I held one hand up to the other and sure enough I could clearly see a shadow cast by Venus! I didn't dare point my scope at it for fear of retinal damage :-) (I did peek at it later as the dawn came up; it is about 1/2 phase now. Its too bad Venus has all those clouds, it would be a nice sight if we could see the surface.)

Finally, just before dawn, we got a shot at Orion for the first time since winter. M42 was its usual glorious self. Jim made my day after looking at it with his 8" and my 12" by saying, "Aperture does have its virtues." I paid a lot for those extra square inches. They make a difference when looking for faint fuzzies but pay off pretty big on the easy stuff, too. NGC 1973/75/77 (which is often mistaken for M43) was pretty easy, too.

All in all, a nice night. Good fellowship, some good seeing, happy newbies, (too much dust), and Cytherian shadows. Amateur astronomy is a cool hobby -- there's always something new!

Bill Arnett; last updated: 1996 Nov 16