An Unexpected Break in the Sky
An Unexpected Change For the Worse

1/02/02: An Unexpected Break in the Sky

About 11:00 last night, was about to turn in for the evening but decided to stick my head out and get a sense of the Moon before so doing.

This has been my "ritual" as of late. Skies above the Santa Cruz Mountains have pretty much been awash with clouds and rain since the ides of December. But cloud thickness does vary and occasionally Selene can be seen doing her best to "part the veils" and show something of herself. Typically, this results in a general brightening of the sky in her general direction. Occasionally, something of a defined limb is possible. Infrequently, sucker holes wander across the sky and expose her disk of various degrees of fullness.

Those same sucker holes may also go on to expose Saturn, Jupiter, Capella. Usually for a few minutes at a time. Under such circumstances, I assess my chances and if particularly hard up for photons, I'll take out the Pup and have a look.

Then the second issue presents itself - The Pup has not been well. Issues with doublet spacing and the "not so central" overcorrection zone mean that views of Saturn and Jupiter are less than enthralling. Capella usually gets most of the tube time as I try one thing after another to resolve doublet spacing and alignment issues.

Last night there were no sucker holes. There was, in fact, a "sucker sky" and I couldn't resist. - It's been much too long...

Last week between holidays I spent some time "pre-aligning" the Pup's optics using the remote cell phone tower. Sky conditions are a huge factor when using this approach. And true to form, the star test on Capella proved that things were still amuck. So after inspecting Saturn (Cassini definite but not especially so), I devoted the next hour messing with the doublet referencing Capella. In so doing, found that I was able to control extrafocal collimation by simply tweaking the plastic screw on object glass retaining ring. In so doing, was able to center a suspected overcorrection zone mid-extrafocal-image. (The intrafocal image was fine.) This result echoed past efforts at collimation - which have also been successful but have never been permanent. Basically, the Pup's positive element seems constitutionally unable to stay properly gapped and aligned. So there is no especial reason why changes made last night should hold...

Currently (at midnight), Saturn now exits the skies middle third. And with Jupiter just past opposition, it begins it's own descent. I turned the Pup on Saturn first. There was no "huge" improvement in the view of Cassini (over that seen earlier in the evening). However, the SEB was a tad more distinct and the planet slid though focus symetrically. I will say this however, increasing the doublet spacing has most definitely improved the color correction. As it stands now, very precise focusing results in an almost entirely "false color-free" image of the planet. One other note, at 120x I was seeing far more of Ring A than I am accustomed to through the Pup. The region outside "frosty the anti-division" was quite extensive and hints of Encke were feasible on eye movement - nothing definite however.

Turned the Pup back on Capella - the alignment had held. But this has often been the case before...

The Pup's views of the Gas Giants have never been especially spectacular - this is Argo's province. BUT I have always felt that an 80mm scope should provide aesthetically pleasing views. When I first got the Pup, Cassini was rarely seen. Meanwhile, Jupiter only revealed vague presentations of the two main belts plus some polar darkening. Neither planet ever showed "crisp edges". The Pup was an obvious "underachiever".

When I started playing with the Pup's mechanical collimation (including lens cell, focuser, and diagonal) there was considerable improvement. Any half-way decent night, I'd catch Cassini. Jupiter's equatorial belts showed irregularities, and on better nights, the NTB and STB could be seen along with a sense of the SEB rift.

But still, I didn't care for the color correction. The gap between Saturn and the rings showed too much "magenta" while Jupiter was far too "yellow". Experimentation with doublet spacing (increasing the gap to about half a millimeter) resolved this issue - but introduced others - the positive element couldn't be consistently positioned (it tended to swim about). And poor handling of the positive element introduced visible scratches in the AR coating.

So there has been a price to pay in mitigating the "color-correction" issue. Be that as it may, there is also no longer an issue. I am now pleased with the way both Gas Giant present in the 120x eyepiece. False color is controlled, limb focus is achievable and focal traverse gives nice symmetrical images.

All this was summarized in last night's view of Jupiter. The NEB showed edge irregularities. SEB suggested the rift. And the NTB was definitely visible. The original Pup - pick of the litter that it was - just didn't compare.

Ported the Pup over to the south viewing station. Found that I could cleanly resolve Alnitak at 120x (greyish, 4th magnitude secondary south of 2nd magnitude primary and 9.5 magnitude come easily held direct one arc minute north of same).

The Great Nebula was just that - Great! At 120x, things thin out noticeably - but variations in surface brightness are more present. Despite a very fine view of three little gemlike stars (and a more difficult and pointilistic fourth) the Trapezium was just that - a "Fourzium".

A night of such stability would probably have revealed E direct in Argo, and probably F with slight aversion - but the Pup needs a far darker night as well - just to catch a hint of these 11th magnitude sweeties using all the tricks of the visual trade...

Ported the Pup back over to the north station and took a final look at Jupiter. Spent a few moments thinking to myself "so close - yet so far".

As I write this, sunlight streams down over the Santa Cruz Mountains. Evaporative steam rises everywhere. There is not a cloud in the sky. A definite possibility exists that I will get my first real night sky in more than a month this night. The Pup remains on the equatorial mount. Before Moonrise, I hope to have been well out and about tracking down deepsky denizens. Hopefully, the positive element will have held alignment. If not, I'll tweak the retaining ring slightly and see if it can be dialed back in. Regardless, well before moonrise the Pup will have surrendered the mount to Argo. And the adventure will continue.

It may be quite awhile before the Pup resumes that particular catbird seat. And when it does, it'll have its "work" cut out for it...

01/03/02: An Unexpected Change For the Worse

To complete the story...

All that evaporation rising from the many backyards, structures, streets, and trees, eventually filled the atmosphere above Boulder Creek with a super-abundance of moisture. As evening settled in - so did the fog. For awhile there was a bit of a "sucker sky" overhead. At it's darkest, could just make out 4.8 magnitude SAO 91611 located southwest of the Great Square's northeasternmost star.

But that was the best of it...

Earlier, managed a pick out Vega much lowered to the northwest. This bright star's bluish airy disk could just be discerned within a tremendous flashing of atmospherically induced flare. Focal traverse showed the Pup's positive element had held collimation well, however...

A bit later, caught Saturn - well into the skies middle third. I could only guess at Cassini and the SEB was just possible - on averted imagination...

Crazy as it sounds, made a sweep for Mars - couldn't find it. Was looking far too west. The Red Planet actually hung maybe an hour past culmination and well above the horizon - simply incredible. The Chariot of the War God seems to be doing everything it can to "run the good race" vis a vis our own Blue Planet.

The view of Mars through the Pup at 120x was minute. Sure, there was some distinct brightening at the south pole. And yes, there was definitely a good deal of "color tinging". As I recall (although I didn't really look for it), the planet was also quite gibbous. But seeing stability wasn't even up to showing small image scale contrast effect along the central meridian - nevermind horizontal maria features.

Except for Vega, repeated these same observations later through Argo - just before losing the sky. Mars at 320x was larger, but there was no additional detail. A study in expressionistic blurr techniques - that be it...

Saturn at same magnification showed no more of Cassini or the SEB than the Pup. And this was a good thing, cause had it done so the optics on the Pup would have been judged abysmal...

Now the Pup is all wrapped up and protected in its travel bag. Argo sits on the Skyview Deluxe mount. My own personal "ship of the skies" awaits somethng of a break in the relentless series of low pressure systems sweeping in off the Pacific Ocean.

One peculiarity noticed in following these systems is that even the occasional breaks between them seem to dissolve as they hit the Northern California coastline. I suspect that the wealth of water deposited hereon uses every opportunity it can to rejoin the great aqueous mass of air above. Such behaviour may not be good for astronomy - but like most elements of the great economies of the natural world, it must be good for something...

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