01/27/2006, Tucson, AZ USA
So far 2006 has not been much for astronomical observations. The last time the 'newt and I were out under the night sky was, in fact, 24 December of '05. In part, weather is to blame, but in truth the climate has played only a minor role in keeping me away from the night sky. There have been other obligations and, well, my seasonal situation to blame. But it hasn't been a complete loss. I'm up before the sun every morning and can usually find an excuse to step outside into the pre-dawn stillness for a look up into the glittering dark. I enjoy the preview of seasons to come these brief sessions provide. Tonight it will still be winter and the Hunter will dominate the sky, but tomorrow morning the Lyre and the Swan will bring a sign of warmer days above the horizon just ahead of the sun.
So far this month two of these all-too-brief looks at the morning sky stand out clearly in my memory. On the 4th I stepped out and found the 27 day old Moon high in the south, a slender curl of silver set against that deep shade of morning blue that extinguishes all but the brightest stars and planets, but does not qualify as daylight. Silver on deepest blue, like an elvish banner in a story Tolkein might have written. Jupiter was higher in the sky, pure and white against the dark, pellucid blue, an elvish gem, perhaps, though not quite bright enough to be a silmaril. I pointed the scene out to my wife, who usually indulges me by coming out to see what has caught and held my attention enough to remain exposed to a very chilly morning. Whatever flights of poetry may have come into her mind were express simply as, "Oh, wow! That's pretty!" Which really says it all.
On the twenty-third, well into the waning side of the next lunation, the Moon again gave me a motivation to stop and stare, not quite oblivious to the cold, but willing to endure it. The Moon was a fat crescent hanging against a black morning sky. The sun had not yet brought any trace of that deep blue morning glow into those cold, early hours, and in the east the stars of early summer were rising. To the south as well. The Scorpion was well up in the southeast and the Moon, with bright Jupiter a little higher and a bit to the east, lit the sky between the stars. The Moon and Jupiter had both escaped the claws of Scorpius, though they were not quite out of reach of the Scorpion's sting. As I stood there, marveling at the stillness of the world below the mythological tableau, a neighbor passed by walking a small, hyperactive dog. He gave a friendly nod, and then glanced in the direction I was staring. "The Moon sure is bright this morning," he remarked. "Yes, it is," was all I had time to say before the impatient mongrel strained at the leash and he did a quick step to keep up. Who was walking whom on that cold morning? The quiet morning was touched for a little while by the tags jingling on the dog's collar, then all was still once more. I eventually went in, a little numb from the cold, as that deep blue began to seep into the sky but before Antares, the red heart of the Scorpion, had lost its gleam.
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12/24/2005, Tucson AZ
8:23 pm MST through 11:30pm MST
I'm one for planning an observing session. I always go out with a list of potential targets that I hope to observe, either on a theme of exploring a constellation (often using Tom Trusock's 'Small Wonders' for my guide) or to "knock off" items on an Astronomical League observing club list. For Christmas Eve I chose to follow the latter course, and so went out with a modest list of double stars and Messier objects. I had a plan and fully expected, because of predicted fine viewing conditions, to make solid progress on these two lists.
Ah, the best laid plans of mice, men, and amateur astronomers...
First, consider my tree filled backyard. By the light of day, I wouldn't part with those wonderful old mesquites for any amount of money. At night, sometimes, with the 'newt set up and ready to go, one or two of them could fall down and I wouldn't be too unhappy. On Christmas Eve, as the calm but chilly night settled, I realized I had been careless in my object selection, and couldn't see some of the stars for the trees. I converted my modest list to a short list and then laughed off the disappointment. After all, the sky is open to the east for me, and with each passing hour new objects rise into view. I had all night, after all.
Did I mention that I'd spent part of the day gardening? No? Well, about those best laid altered plans and having all night...
I started out seeking and finding a couple of double stars. By the time I had logged them (delta Orionis was especially pretty) it was obvious that my daylight activities had come back to haunt me. My back was stiff and just beginning to feel a bit sore. Anyone who has ever used an equatorially mounted telescope (especially a Newtonian on an EQ mount) can see trouble coming. These systems can put you into some peculiar positions when you try to use a finder or a Telrad. Usually this is no problem for me at all. With my observing chair carefully positioned and adjusted to the right height I can use the Telrad and finder - even if they are positioned under the belly of the beast - without becoming an EQ hunchback. Unfortunately, with back pain, the observing chair itself represents an awkward position. I took some aspirin and hoped for the best.
My wife wanted to see M42 in the 21mm Stratus eyepiece, so I went to Orion as soon as it was high enough. It was chilly, without being horribly cold, so getting her to come out was not a problem. Getting her away from the eyepiece was another matter entirely. (This should end the comments regarding what I spent on the eyepiece.) We viewed the nebula together with and without the Ultrablock filter, and curiously enough she preferred the unfiltered view. When she had finally seen enough (meaning the chill got to her - my wife is a tropical creature when she has a choice in the matter) I replaced the Stratus with a 9.5mm Orion Lanthanum Orion eyepiece and gave M43 a good look. I'm forever forgetting to check this one out, with the Great Nebula nearby. As I looked at it, using averted vision with and without the Ultrablock (it really offered no great improvement to this view) I wondered if it would attract more attention to itself if it happened to be elsewhere, far from a show-stopper. It didn't take me long to conclude, no, probably not. Maybe I'm giving it short shrift, having observed it only from within town, but M43 just doesn't ring the bells. I sketched it, with M42 occupying about one third of the FOV for perspective. Feeling pleased that I'd rendered that little bit of M42 so well, I put the Stratus back in tried to sketch all of it. Well, what I produced isn't art, but it will be plenty good enough for the Messier project.
By this point I'd been studying various filtered and unfiltered views of M42 and its surroundings for a little over an hour, and had not been getting up and walking around as often as a stiff back requires. The purpose of the aspirin having been soundly defeated, I quickly realized that an all-nighter was not, in fact going to happen. So I got down to the business of having first light with the recently acquired 4.8mm Nagler. Since I already had the Great Nebula locking in, and the seeing conditions were good enough (4 on the Pickering scale, with a NELM of 4.5) to support 208x, I decided the Trapezium would make an excellent first light object. If I made only one sound decision for this abbreviated session, this was it. I tried the new eyepiece with and without the Unltrablock, and decided the unfiltered view, with the natural color of those bright young stars unadulterated, was the way to go.
And what a view it was! The four main stars gleamed calm and bright, with only a bit of twinkling under such good conditions. The dark bight of the "Fish Mouth" stood out clearly, with the Trapezium seeming to rest on the nebula just at the end of the gulf. The 'E' and 'F' components of the multiple star system were easily detected. But it wasn't any given star or set of stars that made it worth such a long look it nearly finished me off. There was also the ghostly radiant nebula around and beside the stars, showing subtle details I've never seen before. Those bright bluish white stars nestled in their vast cloud nest combined with the detail in the nebula around them to become one of those views through the eyepiece that will haunt me forever. Like looking at Saturn for the first time, there are sights that once seen can never be forgotten. The Trapezium and its immediate surroundings, seen through the 4.8mm Nagler, has place for me on that very short list.
I managed to regain my composure (I have long since learned to react in silence, for the sake of a peaceful neighborhood - the folks around me not taking kindly to their dogs being set off so close to midnight!) long enough to realize that here was a multiple star for the AL list, in as fine a view as I was ever going to have. And so theta 1 Orionis and its surroundings were sketched and safely tucked into the notebook.
Too late I took a walk around the garden, trying to loosen my back. When I could stand the thought of being perched on the observing chair I tracked down M37 in Auriga, wanting a look at it through various eyepieces that had not been in my possession a year ago. First the 21mm Stratus, which gave a fine view of the entire cluster in its context, and revealed clearly the over-all structure of the cluster, though without resolving many of the stars. The 4.8mm Nagler just didn't seem like the appropriate eyepiece for this cluster, so I next tried that Lanthanum. I don't believe the field of view accommodated the entire cluster, but most of it fit in. I noticed that the brightest star, almost at the center of the cluster (anybody know if this star is in the foreground, and not part of the cluster?) has a ruddy or somewhat orange hue. I don't recall picking up on that in previous views of M37. At the higher magnification all the stars were resolved into loops and clumps of stars, but the cluster lost any illusion of density. I sketched both views, since I found the different perspectives an interesting contrast. Another item crossed off the Messier list.
And the last new item, for this night at any rate. I realized at some point that tearing down and packing the 'newt on a cold night with a sore back was going to take time and care, and the sooner I got back to the aspirin bottle (and, man, a heating pad sounded like a great idea, too!) the better. So, of course, I popped the Nagler back in and took just one more look at the Trapezium...
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11/12/2005, Tucson AZ
6:25pm through 8:30pm MST
Seeing: Antoniadi 2 to 3 (occasionally down to 4)
That old devil the ecliptic almost caught me napping. Less than a week before I made the following observations I helped out at the Craggin Elementary School star party, and the Moon - approaching first quarter - was still riding lower in the south than I would like. Still too low for viewing from my backyard. However, this past Saturday when I headed out with the 'newt to have another look at Mars, I was somewhat surprised to see the Moon (somewhere between 11 and 12 days into the lunation) fairly high in the east, perfectly for viewing. I discovered last spring (another star party) that while I could recite the words describing the Moon's motions through the sky, I really lack an intuitive understanding of the phenomenon. While I work on that strange little sticking point, the Moon from time to time surprises me.
The early evening seeing conditions were pretty good, so between an early and later session with Mars, I took a long delayed trip to the Moon. Having done none of my usual planning for a moonwatch, I defaulted to a style of observation I employed once upon a time when the Old Scope (60mm refractor) was still usable. Sometimes in my notes I refer to the process as 'feature hopping,' at others I call it 'sliding down the terminator'. Tonight it felt more like a slide, curving out from and back toward the terminator. I started at the top of the field of view (alternating mostly between a 10mm and a 6mm Plossl for 100x and 170x with a VPF used only on the 10mm ep) which means I traveled south to north, the 'newt being a Newtonian, after all. And the first thing to catch my eye (after I tripped over Tycho, of course) was the crater pair Klaproth and Casatus. They appear to be scrunched together, with a somewhat straight and low common wall in the center between them. Of course, the configuration is the result of violent impacts, randomly distributed, but it really does look as if something was in the way, and either Casatus was pushed north, or Klaproth shoved south to make room. The floors were smooth and gray, and Casatus C was visible in its main crater. What made the duo stand out was that common wall, caught by the morning sun just so and casting a bold, and jagged shadow almost right down the middle, dividing the craters more clearly than is usually the case. For some reason it brought to mind a gigantic sundial. If you're ever on the Moon and need to know what time it is, head south.
The sun had long since risen over Clavius, so it was the wrong time to see the bulge of the crater floor, and not a great time to count craterlets. I could easily see the bigger ones that line up in a way that makes lunar scientists believe they came from a major far side impact. With a little patience I could count 10 craterlets, some on the edge of resolution, and visible because their west facing walls gleamed like little flakes of silver over scraps of shadow clinging to western walls. Clavius wasn't the only crater with craterlets showing. Blancanus had a few of those silver and black flecks in its southeastern quarter.
I took a moment with Longomontanus because, according to Wood, this is an example of a large crater overlapping a smaller, older crater. What we usually see is the reverse, with a big, old crater battered with any number of smaller, newer impact scars. I'm assuming that what is referred to here is Longomontanus B. After this contemplation I hopped over to Scheiner, where I was unable to pick out the mysterious ridge that Wood mentions in The Modern Moon. While there I noticed a chain of wide pools of black shadow. Running more or less northward, these were the craters Wilson, Kircher, Bettinus, Zucchius, and Segner. They looked pretty uniform in terms of size and the amount of inky darkness contained. Their rims and the spaces in between were mostly sunlit, so the effect was on large beads of jet in an old silvery chain.
Next on the inconstant path generally trending northward was funky foreshortened Schiller, with the broad plain often label the Schiller-Zucchius Basin extending beyond it to the terminator. There's a ridge that divides the western portion of Schiller, just poking out into the crater, and this feature was well lit along its upper edge, with a lake of shadow at its foot.
The 'newt and I wandered up into the area west of Hainzel and south of Lacus Excellentiae, where several sharp shadow triangles marked the positions of peaks, none of which turned up in the references I brought out with me. In one area it looked as if giant black shark teeth had been washed up on the shore of the lake. Still wandering, we moved a bit away from the terminator and drifted out into Mare Humorum. There was not much shadow relief left in the Humorum regions, but some interesting features caught my attention all the same. There was Promontorium Kelvin gleaming in the sun, and portions of Gassendi's rille system could be made out. Even easier to see, in spite of the lateness of the Lunar hour, was Rima Hippalus curving down from its partially flooded parent crater, down into the highlands east of Promontorium Kelvin. The craterlet Hippalus B rests against the inner curve of the rille, as if poised to roll right out of Hippalus. On the western side of the mare, Rupes Liebig was easy to spot, since the shadows were longer over there. This fault splits between Liebig D and Liebig F, like a river flowing around an island. Lots more to look at in the Mare Humorum, and I looked at quite a bit of it, but this is already running long, so it's time to slide ever northward.
And it's much easier to slide over the Oceanus Procellarum. I wouldn't call the region featureless, but it certainly is less busy that points south. I examined the ruins of Letronne, with its rim intact only on the high side, away from the lava flows that formed the great Ocean of Storms. The Oceanus Procellarum is marked in many places by the ghostly skeletons of craters consumed during its formation, with Flamsteed P serving as a fine example. It looks like a soap bubble caught at the end of bursting, or a single-celled organism that, having succumbed to cytolysis, has spilled its organelles (Flamsteed, Flamsteed A and B, and Dorsa Rubey) across the microscope slide.
Taking a curve north and east of the disasters - real and imagined - the ocean brightens noticeably where the rays of Copernicus and Kepler intermingle. Near here I managed to locate the crater Seuss, but not the rille of the same name. For some reason it feels like this admission should be set to rhyme. I veered back toward the terminator, where I found the rim of Marius gleaming against the nightscape beyond it. Further north still, and the eastern edge of the Aristarchus Plateau appeared, just then being touched by the sunrise. The west wall of Aristarchus crater was bathed in morning light and for first time I could see, clearly and without any second guessing, the banded patterns for which the crater is known. Actually, calling them bands overstates the appearance. At 170x in an 8" Newtonian they appear as thin, delicately inscribed lines of silver and ebony. However you want to describe them, they were beautiful, and looked best at relatively modest magnification. At higher powers (more than 200x) the appearance of delicacy was utterly lost. When I could bring myself to look away from the walls of Aristarchus I realized that the Rupes Toscanelli stood out as a short, bright feature against darker lands to the west. Nestled between ghostly Prinz and the Montes Harbinger I could just make out a loop of the rille system named for Prinz. Curiously, I could not pull off the same trick with those associated with nearby Aristarchus.
Away from the terminator again and north, over the crater Delisle and its nearby mountain namesake (with the merest scrap of shadow clinging to its west side), to the northern highlands that jut out into the Oceanus Procellarum, between the Mare Imbrium and Sinus Roris. Not far away are the great volcanic domes Gruithuisen Gamma and Delta. Seeing conditions were not quite up to picking out the crater at the top of Gamma (although I'd swear I was just this side of seeing it when I pushed magnification briefly to 340x), but this was still one of the best looks I've had at these domes - fantastic and incongruous lumps of lava on the Moon. From there I found my way east to Promontorium Heraclides, then followed the Montes Jura in their arc around Sinus Iridium to Promontorium Laplace, which still cast a significant shadow at its foot. Starting from where Bianchini punctuates the Juras, I backtracked a bit, peering into the still shadowy craters Bianchini, Sharp, and Mairan.
At this point, as I continued north the terminator curved east to meet me, and would very soon determine the end of this journey. Into the Mare Frigoris, past Foucault and Harpalus to J. Herschel, a wide and shallow-seeming crater. Such craters usually have smooth lunar gray floors, but this one always looks rough, as if someone had just raked over a gravel lot or driveway. (The crater W. Bond looks like this, too, when the light is just so.) I can go a little further north, yet, before I leave daylight, and a trio of jet black circles, rimmed in silvery gray, catch my eye as I do so. It's a shorter chain of black jewels than Wilson, Kircher, Bettinus, Zucchius, and Segner far to the south, but the effect is very much the same, of flat round gems carved from jet, set in slightly tarnished silver.
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