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Mad Meanderings under Temperature Inverted Skies

It’s been a looooonnng winter already.  Of course, if you go by the calendar, we’re only a month into winter.  But I tend to identify winter with the onset of the November rains, which typically don’t start here until the middle of that month.  This year, though, the rains were over-zealous, picking the middle of October to start falling from the skies – seventeen inches worth of falling in fact, in only the last two weeks of the month.  They were kind enough to take a short break in November, and even a couple of times in December.  But each time, the seeing was so poor it didn’t even deserve a place on a chart.

So when I saw a forecast for a string of five or six clear nights in the middle week of January – most of them moonless, even – I was as thrilled as a chocolate addict turned loose in a fudge factory.   That is, until I saw those two seemingly unrelated words:  temperature and inversion.  Put ‘em together and you’ve got astronomical problems.

Still, I adopted optimism as the best approach – and on that first night, as I looked up into a dark sky of gleaming stars twinkling with unrestrained abandon, I decided to turn the night over to my 100mm f/13 Skylight refractor, which has punched through poor seeing on many a mediocre night.

Not this time, though – mainly because the night was a whole lot worse than mediocre.

Polaris on a better night  (click for a larger version).

Polaris on a better night (click for a larger version).

Polaris, my first target, looked like it had had a bad hair night.  There were so many spikes exploding from its ragged almost-round edge I almost thought I was looking at solar flares.  Needless to say, the secondary was swallowed up in all that aberrant light.

I gave Jupiter a try, just to see if conditions were as bad in another part of the sky, and was treated to an amorphous blob of wobbling white light with occasional glimpses of what might have been a pair of horizontal lines running across it’s width.   It reminded me of a distant basketball bouncing on a stellar court, and I wouldn’t have been the least bit surprised to see the words Spalding or Wilson stamped across it.

Rats.

Since this was obviously pointless, I returned all the astronomical hardware to the house, pulled up the NOAA weather site to see what I could see, and found the atmospheric soundings over Salem, Oregon – which is about 100 miles from me as the crow flies – showed an air temperature of thirty-two degrees (F.) at 2200 feet of elevation, and fifty degrees at 5000 feet of elevation.  Even though Salem was trapped under a large cloud bank by the temperature inversion, and I wasn’t, I did have the thirty-two degree temperatures.  And that explained that.

So the next night, thinking I could sneak under the stellar radar by going smaller, I turned to my 80mm f/15 Mizar refractor, which has taken the twinkle out of many a dancing star.   Aber nein, as they might say in Deutschland, which translated means no way, not tonight, not last night, not tomorrow night, maybe not ever.

Twinkle, twinkle little star,
How rotten and despicable you are.
You’re gonna drive me to the nearest bar.

Back into the house again.

Now —– night number three:  clear and almost stable at dusk, clear and not stable at all an hour later, and  unclear, unstable, and totally un-thrilling a few hours after that.  I had even set up the D&G five inch f/15 in the unaccountably optimistic hope the sky conditions would improve.

Many words worse than rats rattled the air that night.

Which brings us to night number four.

I wasn’t going to try it.  At 7 PM, Orion’s belt stars were dancing like blinking white Christmas tree lights.  At 10 PM, they were still dancing, but I noticed the sky was incredibly sharp and transparent, despite being bathed with first quarter lunar light.  Tempting, yes – but no, no way — I’d had enough of dancing fuzz balls of spiky white lights.  Still,  I couldn’t resist taking a peek at midnight – and when I did, I noticed the dancing had dropped from the whirling dervish level to a mediocre mad prance.   Hmmmmm.

The Silver Streak, poised for action (click for a larger view).

The Silver Streak, a gleaming home-made 60mm f/16.7 refractor with a Carton lens, poised for action (click for a larger view).

The Silver Streak was sitting in the corner of the living room, it’s gleaming silver cylinder highlighted by a few beams of yellow-white moonlight that had found their way through the venetian blinds.   It was an alluring scene I couldn’t resist.  The scope was sitting on its mount, so I grabbed the whole affair with one hand, marched it out to the deck, set it down, and gave it some time to cool down to the forty degree temperature.

Since it was pointing at Orion, which had now started its downhill trek on the west side of the celestial meridian, I aimed at the Trapezium and discovered a blob of mostly un-focused starlight at the center of the nebula.  Ugh.  I panned up to Sigma (σ) Orionis and could barely recognize it.  Then I pointed the long silver tube up to Jupiter, and at least was able to recognize it was larger than a star – much larger, of course, and almost as unfocused.  Disgusted, I walked away from the scope and looked up at the sky.

How in the world could a sky look as beautiful as this one did, and still be such an infernal disappointment in a 60mm f/16.7 refractor?  Arghhhhhh!

Then, looking to the east, I spied Leo on an upward lope over the roof of my house, caught sight of Algieba, and decided to give it a try since it was in a totally different sector of sky.  Unsplittable it was in the 26mm Celestron  Plössl (38x) I was using, but almost binary-like in a 20mm TV Plössl (50x).  So OK, let’s take a gander at Polaris, I thought to myself.

Over to the north we went, the Silver Streak and I, and it was almost like old times!  Polaris was a sharp little dot of yellow light, and its ninth magnitude companion was a weak spark of barely breathing dim white light —  just like I remembered from those distant pre-rain soaked October nights.  What a sight for ravenous eyes starved for sharp pinpoints of exquisitely focused photons framed against a black backdrop!

Where to next, I wondered.  Back to Orion?  Well, why not, even though its belt still looked like a trio of slightly subdued white strobe lights.  The Trapezium hadn’t improved much, so I panned down to Iota (ι) Orionis.  And when I could get a precise focus — and when it would hold still — I was able to catch a very soul-satisfying glimpse of Iota’s (ι) 9.7 magnitude “C” companion.

So I slewed my way north to Sigma (σ) Orionis territory – again — and sat down with firm intentions of sitting tight until I could pry it apart, along with its delicate and fragile three-starred neighbor, Σ 761.  Now Sigma (σ) Orionis is a quadruple star, but the “D” and “E” companions are about all you can coax out of hiding with a 60mm scope – and that’s all I really wanted to do.  With some patient persistence and a heaping helping of averted vision, coupled with some focuser finesse, I got ‘em.

Companions in multiple-stardom -- Sigma Orionis is a quadruple (actually a quintuple to be exact, but the fifth star is out of our range), and Σ 761 is a genuine triple.  (East & west reversed, click for a better view).

Companions in multiple stardom:  Sigma Orionis is a quadruple (actually a quintuple to be exact, but the fifth star is well out of our range), and Σ 761 is a genuine just-as-you-see-it triple. (East & west reversed, click for a better view).

Meanwhile,  over on the left side of the eyepiece (northwest), where I had been casting an occasional curious glance, was Σ 761.  Delicate and fragile I said they were, and they are.  When I had first viewed them at the beginning of the evening, they were an inseparable blob.  But not now.

The 7.9 magnitude primary stood out distinctly at the top of the triangle it forms with the other two stars – no awards are won for picking that one out of the sky.   The trick – and it certainly is a trick in a 60mm refractor on a night of poor seeing – is to separate the 8.4 and 8.6 magnitude “B” and “C” companions.  The two stars just don’t lend a lot of light to the cause in a sixty millimeter lens — and the 8.5 arc seconds that separates the two stars may as well be half that distance for as difficult as they are.

So when I saw those wiggling half-white whispers of light as two separate, two ghost-like, two spectre-ously illuminated cotton-like wisps, I was thrilled right out of my Plössl pickin’ mind!  It was all I could do to stifle a rebel-like yell that would have raised every law-abiding citizen of this small coastal town six feet out of their bed in sheer terror.  Fortunately, I was able to wedge my fist firmly in my mouth and preserve their restful slumber.

When I finally calmed down and felt it was safe to remove my fist from between my teeth, I decided I would return to Algieba in hopes of being soothed into a stupor by its golden charms.  Leo was on his final approach to the celestial meridian by then, so I tilted the illustrious Silver Streak up into the southern sky, centered Algieba’s golden glow in the finder, peeked into the 20mm TV Plössl still parked in the diagonal, and allowed my right eye to be bathed by the warming rush of yellow-gold photons.  And, separate as separate can be, was that diminutive dot of green-yellow-gold secondarial light.

Ravished again I was.

Glowing in gold, and always a glorious sight to behold! (Click for a larger view).

Glowing in gold, and always a glorious sight to behold! (Click for a larger view).

Up to this point, I had resisted going beyond the 50x provide by the 20mm TV Plössl, but it seemed there might now be some room to maneuver the magnification higher, so I dropped a 17mm Faworski Ortho (59x) into the Silver Streak’s focuser and put my breathing on hold.  It wasn’t meant to be, though — that mere 9x increase in magnification was beyond the limits of the bad-seeing barrier.  What I found was two ir-rhythmically throbbing globes that wavered between almost round and half flat, the flat part being restricted to their bottom sides.   I’ve never quite seen anything like that – when they would go flat, both of them would be flat at the same time and in the same place.  As if the air had temporarily been let out of them.  Very  strange.  Inexplicably strange.

But at that point, I decided enough was enough.  It’s best to salvage what you can from a night like that one, and if nothing else, I had at least re-established a connection of sorts with the stars.

And although I hesitate to point out the obvious, I feel compelled to single out the humble contribution of Old Silver Streak and its twin lenses of achromatic delight.  Never — ever — under-estimate the ability of a sixty millimeter refractor!

Clear and STABLE skies!  😎

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4 Responses

  1. Same thing on this side of the river, John. Very unstable skys! That and lots of clouds too! Nice time to work on the scopes!

    Mike

    • You must be on the north side of the Columbia, Mike. The skies over the western slopes of the Cascades are not the most friendly in the winter, that’s for sure!

      John

  2. LOL! When I said “this side of the river”, I meant this side of the Mississippi! 🙂 I’m all the way over on the east coast, basically a stones throw away from your old friend Greg Stone. Less than an hour from him by car, I am. We often fall right under the jet stream, and between that and the temperature fluctuations we learn to like poor seeing. 😉
    Mike M.

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