Special Observing Report
Backyard, Boulder Creek: 1/29/02


"You know Jeff, you're simply too verbal and need to do something about it.", said me to I, or was that I to me? Being at least cursorially familiar with the bicameral peculiarities of the human brain, I knew that painting and other visual arts were just the ticket. So, not too long ago I took up sketching.

As it always goes, once you answer one question, a whole slew of other questions follow in its train. So the follow on was obvious: What exactly should I sketch? Hmmm... Natural scenary? Still life? Portraiture? Nudes? Sure, that last worked for me! And as usual once you settle on something a whole train of issues crop up. Just exactly where was I gonna get a steady stream of models? Hmmm... Surely you don't just walk up to some babe and say "Hey, I need to balance my hemispheres, would you mind taking off all your clothes?" No, that would just not cut it...

So what else "turned me on"? Hmmm.. The sky, yah the sky! There's all sorts of shapely stuff up there. You got Queen's and Princesses. Then here's that babe - Selene. Lot's of nice "Gal"-axies. But of course, all models don't have to be female, do they? Sure, why not a few "gods" they have "Heavenly Bodies" too don't they"? (You knew that one was coming didn't you?). Wouldn't be quite the same, but it would ensure that I'd never be at a loss for things celestial to draw, after all...

So tonight in keeping with this line of thought, I went "sketch happy". Sky stability was decent (7/10). Transparency passable (~4.5 overhead due to high clouds). An early third-quarter Moon would be rising not too long after skydark anyway... And I knew I'd have a chance to catch Mars early, shift over to Saturn, follow 'Ol Jove. Do some "simple" deepsky, then dote over Selene (if sky stability wasn't too bad down low early in the evening...)

And that's just about how things turned out. (I even love it when realistic plans come together...)

By 6:00 o'clock things were dark enough to catch a first magnitude, 5.5 arc second sized Red Planet high to the southwest. Even at 210x, the planet was incredibly small. In fact, less than twice the apparent size of 3.3 arc second Uranus! Unlike Uranus though, Mars gets plenty of light. And that light is reflected in various interesting ways - all depending on the albedo of surface features over large swaths of the planet. Dark maria, though lacking precise definition, will reflect less light. Meanwhile, bright laci do the opposite. Throw in some super bright polar caps, a little electric blue limb haze, add some high deserts and there you go - a "sense" of surface detail. And that's what the image at left pretty much captures - the subtle play of the bright against the not so bright, and the luminous against the obscure.

Times did occur when seeing improved enough to make out delineated detail. But this was all too infrequent. So infrequent that I found it impossible to view Mars at anything above 210x. Stability in that part of the sky (over heated structures on a very chilly evening) was about 5/10. And what detail I could make out reminded me of Erythraeum - but actually turned out to be a combination of Mare Sirenum (rotating in) and Aonius Sinus (on the way out).

Having started the evening with one bright planet, I wanted to make sure to sketch the others. So, next stop was Saturn. To be frank, Saturn is not one of my favorite "sketch" studies. There really is no easy way to handle the rings. The image at right started with an ALPO (Association of Lunar and Planetary Observers) sketch blank. It's probably intended for sketching what little in the way of cloudtop features are susceptible on the planet. But my interest lies primarily in the ring system. So I made do...

In looking at the drawing, you might say that ring presentation is pretty good - but it is actually even better than that. In fact, the planet's minor axis is surmounted by the Ring A's minor ansae at both extremes. The blank used for this drawing is last year's version and I really should come up with something more appropriate to the need...

In regarding this image you might guess that seeing stability was pretty good too. Most of the time it was in the 7/10 range. As with Mars, I used 210x (25mm Ultrascopic with 3x configured barlow). When the seeing did improve (briefly) to 8/10, several changes occured in the view: Cassini became well defined - to use fellow observer Otto Piechowski's description "ribbon-like". The Encke Minima was caught - just outside Cor Boerrevoet's "Frosty, the Anti-Division". And the southern frontier of the South Equatorial Belt would distinguish itself.

Some things that couldn't be readily seen: Crepe Ring inside the inner dimmish frontier of Ring B. Blue-Gray mottling in the South Polar Region. The light "sash" above the SEB. Nor were there any sense of belt irregularities along the northern frontier of the SEB. These "Saturn on-the=edge" features all require more extended periods of 8+/10 seeing to make out. Probably because the eye is not quick to pick up on subtleties...

What could be seen was Ring A, Ring B, Cassini Division and the planet's rather angular shadow against trailing and posterior Ring B. On the planet, the Equatorial Band (shaded by Ring's B and C), the northern frontier of the South Equatorial Belt, and some albedo gradient to the southwest and polar regions, were all easily made out.

I've been spending a lot of quality time with Jupiter as of late. The evening's view was unexceptional, EXCEPT for a transit by Ganymede along the South Temperate Belt. Io transits are quite common. But over the last year or so, I recall seeing maybe only two other Ganymede "rites of passage". And they were all spectacular! First, the shadow is much larger. Second, it progresses very s l o w l y. Meanwhile, Ganymede tends to lie well ahead of its "dark twin" on the planet below.

Three other noteworthy observations about Jupiter: The eastern (ingressing) segment of the North Equatorial Belt (NEB) appeared "thinner" than that along the central meridian. Along the central meridian itself and embedded within the NEB was a large dark barge. Finally, even under less than ideal seeing (7-/10), beginning to see that thin, wispy Equatorial Belt (EB) with greater frequency.

This last puzzles me. Previously I considered it strictly a "8/10" preogative. Now it's beginning to turn up with regularity under lesser (7/10) conditions. Haven't had to play with Argo's collimation since last Summer. Hmmm, maybe this "right brain" drawing practice really works!

As mentioned, wanted to do at least one "deep sky" sketch this evening. Drawing at right however, is not it. I've mentioned Iota Cassiopeia so many times in reports (especially during last year's winter series) that I felt a drawing was needful. At 120x, Iota resolved cleanly as a triple - colors warm yellow, aqua, and turqoise. The eight magnitude tertiary trails to east and seventh mag secondary leads the fifth magnitude primary slightly south.

If you count the stars in the image, your tally should be thirteen. (This assumes you accept the fact that there really is an Iota-B.) Among those thirteen, is the roughly 12.5 magnitude star I use to judge transparency. (That star is located at the 1 o'clock position north-northeast of the Iota triple.) It is the only star I allowed myself to add to the image that could be seen with averted vision only. It is also the main (but not the only) reason I did the sketch. Now, assuming that only twelve stars could be held direct in the field at 120x, and that the eyepiece has a 60 degree apparent field (actually 52) then, based on a rather fanciful notion I have, the limiting telescopic threshold magnitude at the time was 12.1. - Not bad at all.

(Sorry folks my left brain just had to express itself definitively in this report...)

Now, this next sketch was also done at 120x. And it, of course, shows far more than twelve stars! (Please feel free to count them if you like and send me an email...) So the sky must have suddenly gotten a lot clearer! Assuming a hundred stars are present, and using the star count method referred to above, Argo would be showing stars down to magnitude 13.6! (This is possible - but not tonight. - OK left brain, bow out now.)

In the sketch at left, the stars are far too well organized to represent a "random distribution" in the night sky. They appear to run in "veins" and show a certain "connectedness". One might suspect that they are part of an open cluster. And that is very much the case. The question remains: Which one? (A hint: "Now is a good time to be looking up.")

Even as I worked the previous sketch, Selene cleared the Santa Cruz Mountains. Having entered the third quarter, the terminator lay along the Moon's leading edge - something that easily confuses me. My only lunar map does not provide particularly good images of this part of the Moon. (Just as well it doesn't provide many labels either...) Suspicions are that this is the "Behaim" region (due east of Mare Nectarus and southeast of Crater Langrenus.) Whatever its true identity, this was certainly the most engaging part of the terminator! What immediately struck my eye were the two promontories at left. It was only afterwords that I came to really appreciate the gentle play of light and dark along the small maria's rim, and the frozen wave caught right of the base of the twin peaks. Amazingly enough, despite less than ideal sky conditions, I actually enjoyed seeing the Moon tonight. (That right brain loves everything!)

Taking pencil and paper to hand is not something that comes easy to me. With words you can always fix what you break - leaving nary a scratch. Sketches require a bold, confident, and well-practiced hand. They also require a lot of patience! I can think of no better reason to take up and develop such skills than the Night Sky - unless of course: "Say, I need to balance my hemispheres, would you mind taking off all your clothes?"


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