04/05/2008, Farnsworth Ranch, AZ
Seeing: P. 4
Transparency: (NELM) 6.0 (SQM) 21.55 at 10:16pm MST and 21.65 at midnight.
Weather: occasional light breeze, warm at the start (low 80s F) dropping to the low 60s by midnight.
Instrument: SVP8EQ
Eyepiece/filter list: 21mm Stratus, 5mm Stratus, 32mm Agena SWA, 9.5mm Lanthanum, 25mm Sirius Plossl, 10mm Sirius Plossl, 2x Barlow, 4mm UO Orthoscopic, Paracorr.
Time for the annual All Arizona Messier Marathon. I attended, but this year decided to use the time under dark skies for observing, and let others run the marathon. As a result I was able to spend a relaxing evening with friends while making significant progress on the AL Messier Club project. I also wanted to take care of some AL double stars, but when it turned out the seeing conditions were not the best for double star observing, I elected to skip those objects and focus my energy on the Messier portion of the list. As a result I was able to observe (in most cases, re-observe) seven Messier objects and produce credible sketches.
I arrived later than intended and found Ron, Jim, and a guy named David crowded into the shade of the back hatch of Ron's SUV. The plan was to set up the Big Top and provide shade for the early arrivals, but the west wind that kicked up that afternoon made it impossible to do so, and we just made do with the shade of vehicle. Fortunately, though it was a bit on the warm side, it was not uncomfortably so; the wind had that benefit, at least. The wind was a seriously mixed blessing, since in addition to knocking down shades erected earlier in the day and flattening a tent or two, it spawned some powerful dust devils when wind met updrafts. One of these upended an 11 inch SCT and left it in pretty bad shape. (The owner packed up the damaged telescope and drove off shortly after I arrived. I can't begin to imagine how bad he must have felt on the long drive home.)
The afternoon dragged but there was enough conversation to divert us until the sun settled low in the west and the wind, mercifully in keeping with the predictions, dropped to a gentle breeze. (Later in the night it would become no more than a fitful whisper out of the south.) There was the usual sunset gathering and instruction session, showing a smaller crowd than last year's marathon. Apparently the fact that it would not be possible to see all of the Messier objects this year put some folks off, although the (unfortunately accurately predicted) seeing conditions and the constantly rising price of fuel could not have helped. (The number of attendees has not yet been posted on the SAC website as I type these words.) With the lecture completed the crowd dispersed, and a night of star gazing began.
I was anxious to nail down one object in particular as soon as it was dark, since M79 in Lepus was about to disappear into the sunset for the season - again. While I waited I scanned the sky with binoculars and enjoyed the peaceful process by which the sky darkens and the stars begin to appear, a few bright ones here and there, at first, then in rapidly swelling legions. Fragments of conversation drifted through the air as marathoners started gearing up and searched for objects made elusive by twilight, but that would not be found if they waited for complete darkness. As usual, the only clouds in the sky were in the low northwest quarter of the sky in which M31, 32, and 33 are to be found. The oft repeated refrain of "Got it yet?" was usually followed by a vexed denial. A bit past 8pm the sky was dark enough to do M79 justice, and I got started.
M79 was a quick find, mostly because this is not the first time I've tracked it down. I used the 25mm Plossl as a finder eyepiece at this point, and in it this globular cluster formed a faint, fuzzy ball in a fairly busy star field. Working from past experience I went straight to the 5mm Stratus, an eyepiece that usually works very well on globular clusters. In it M79 dominated the center of the field, a globe of hazy light that faded away into the sky with edges that were difficult to discern. As usual the sketch I made exaggerated this "edge effect," although having learned to use a blending stump for sketching such an object, the exaggeration is not nearly as pronounced as in my earlier sketches of globs and galaxies. This one technique, by itself, has made my copy of Astronomical Sketching a worthwhile investment. The glow of M79 is pretty uniform, with only a hint of a central condensation. In the past I've though I could see a bit of graininess to the cluster, that hint of stars on the edge of resolution. Low elevation and poor seeing probably conspired to prevent such an observation this time.
Jim started making "Oh, wow," comments, and when I asked what was up (realizing as I asked that he was not using his big dob) he pointed out the zodiacal light rising up out of the west, with the Pleiades embedded near the apex. The best way to describe the soft glow, quite clearly visible, would be to image the ghost of the Milky Way seen from a site not quite dark enough. A beautiful sight to contemplate, and thanks to Jim for pointing it out.
I wanted to take on M1 next, but it was not quite dark enough at that point (I thought) to get a good look. (The look I had at this point turned out to be as good as it was going to get.) While waiting, I decided to have some fun with the new 2 inch eyepiece and the Paracorr. I'd just seen a great view of M42 through Ron's big SCT, and put the same object in the new eyepiece/Paracorr combo so we could compare views. No direct comparison could be made (of course) due to different aperture sizes, but the differences in view between the two scopes was edifying. Curious about how the Newt performed, Ron brought several wide field eyepieces over, and we experimented. I did not take note of all of the examples, but two stand out. First was the William Optics 33mm UWAN, the performance of which was (to my eye) identical to the 32mm Agena SWA. I'm not familiar with the William Optic eyepiece line, but Ron seemed surprised by my reaction. The other outstanding memory of the brief eyepiece swap was the 28mm Pentax XL, which gave (in the Paracorr, at least) the finest view of the Great Nebula the Newt has ever provided. I'd put that eyepiece on my wish list, but they are apparently no longer in production these days, and on the used market seem to be as rare as the proverbial hen's teeth. I fully expect that, when I do find one, the price will not make me happy.
At last I decided to observe and sketch M1, making careful use of a blending stump, yet again. Even under fairly dark skies, this object is at best subtle, the faint fuzzy of faint fuzzies. After swapping eyepieces in and out, I settled on the old 17mm Celestron SMA, not so much because it gave a superior view but because adding magnification didn't get me anywhere. In tonight's view is was a fairly uniform glow that faded gradually and a bit raggedly into the sky around it. It's easy to see where Messier might have gotten his false comet idea from this object.
It was at this point that I discovered the seeing conditions would not support most of the double stars on my list. I gave a couple of these a try, and decided to concentrate my time under dark skies on the Messier objects instead.
The next Messier object I attempted was M93, which was by then also getting a bit low in the southwest. From past experience I knew this object could be spotted in binoculars, so with a suitable chart under the red light, started scanning Puppis. In my first sweep, just as I realized I was pointing the binoculars a bit too far south and east, a round gray patch caught my eye. I noted its location and, checking the atlas, realized I had accidentally "discovered" NGC 2451. In the Newt, using the 21mm Stratus, it was a wide scatter of more than a dozen stars, many distinctly yellow or blue, and one prominent star (C Puppis according to NSOG) that was orange. It was an unexpected pleasure, and a beautiful diversion. In a few more minutes I'd tracked down and had in view M93, a much less colorful gathering of a couple dozen stars, arranged in pairs, trios, and quartets. The cluster was set in a fairly busy field of view. I ended up sketching it in the 25mm Sirius Plossl, stuck into a 2x Barlow.
Sketching open star clusters can be a time consuming process, and by the time I was done with my rendering of M93 it was nearly 10pm. The decision to blow off the double star list was proving to be a good one. M50 was up next, another loose open cluster with a mix of a few (maybe 10) brighter and numerous fainter stars. There was a triangular asterism that seemed to dominate my impression of the cluster, and what had the appearance of a double star to the north, one member of which was distinctly reddish. This cluster was unusual tonight in that I have not observed it before, quick looks during Messier Marathons notwithstanding. As a result, I spent a significant amount of time looking at and sketching M50, time well spent as this is a very attractive star cluster. The 25mm Plossl did this one justice.
After a little time walking around and visiting the neighbors to help clear my head (it was past 11pm by this point) I next tracked down M48. This is another bright and beautiful open cluster, a characteristic shared by many Messier open star clusters. I used the 21mm Stratus on this one, and made a sketch that probably did not do the busy star field of the cluster justice. The west side of the cluster seemed to me to be more concentrated, with stars arranged in looping chains that seemed to open up somewhat to the east. This was another time consuming sketch, and at some point I made an arbitrary decisions to stop plotting ever fainter stars.
Midnight came and went. I took another break, refueled, and visited some more with the neighbors. When I went back to "work" I tracked down my only galaxy for the night, M106. Using the 21mm Stratus as a finder eyepiece, and starting my star hop with beta Canes Venatici, I made another accidental "discovery" when I found the galaxy pairing of NGC 4485 and 4490. A quick look with the 9.5mm Lanthanum verified what I was seeing, but I did not linger. It took a while to find M106, an indication that I was wearing down and coming up on the end point of the observing session. But I did find M106 and sketched it, still using the 9.5mm Lanthanum. This galaxy was elongated north to south, with a gentle brightening near the core. This object, also, was one I have not previously observed, so I lingered over it, not starting to sketch it immediately, contemplating its enormity and distance. Galaxies always have this effect on me, and when the night is growing longer and I've started to wear down, it grows easier to fall into reverie and stay there for a time. M106 ended up being the sight, through the Newt, that appeared behind my eyelids when I finally gave in to the need for sleep.
Which I was not quite ready to do, not just then. Saturn was high in the night, and seeing conditions or no, I felt a need to pay my respects. It was not the best view I've ever had of this world, so much closer that M106 that it almost seemed cozy. But in moments of fleeting calm I could glimpse (using the 4mm UO orthoscopic) the Cassini division, polar duskiness, and the spark of Titan. A poor view of Saturn beats not looking.
It was pushing 1pm, and memory prompted me to scan the low south with the binoculars, seeking and finding Omega Centauri. I was curious to see what the Paracorr/21mm Stratus combination would make of this globular cluster. I was not at all disappointed. Seeing conditions were not an issue here, so low in the sky; you expect it to be pretty poor. In fact, the view was steadier than I expected. The cluster was diffuse grey ball that faded into the sky around it in that tattered fashion you can sometimes see with globulars. Across the surface there was a graininess, almost having the quality of a texture. Omega Centauri filled the central third of the field of view, more or less. I only rarely have the chance to glimpse this one, and it isn't something I pass up, a sentiment shared by Ken, who was set up just to the south. He was running the Marathon, but had taken a moment away from it to do as I had just done, and invited me to have a look at Omega Centauri through his 16 inch dob. That's not an opportunity to be passed up either. With the greater resolving power of the big dob, what in the Newt appeared as a slight grittiness on the surface became the glitter of stars resolved, or just on the edge of it. An amazing thing to see in the first hour of a Sunday morning.
The view of Omega Centauri through a 16 inch telescope woke me up enough the I decided to go for one more Messier object, M68. Proof that I really wasn't as awake as the view through the big dob made me feel came when I found it difficult to hop to this more distant globular cluster, but I finally managed to find it. (Especially frustrating, since this is one of those Messier objects I've observed but not sketched in the past.) Unlike M79 at the start of the night, M68 has the appearance of structure, with a brighter core and distinct halo. There was no sign of stars resolving in the face of the object, but I could just make out the irregularities that other observers report as mottling or dark lanes. To my eye the cluster was not completely round. I used the 9.5mm Lanthanum to sketch this one.
With M68 my night came to an end. Carter and Ken were still working their way through the marathon, but I had accomplished just enough by this point that pushing it seemed difficult to justify. It had been a busy day just getting to the marathon site. It all caught up with me, and I decided not to fight it. Usually I crawl into the Subaru with reluctance, not wanting the night to end, but this time it felt like the right thing to do. I woke shortly before dawn, with a pearl grey glow in the east and Jupiter shining like a silver beacon in the southern sky. Marathoners were drifting around the field, comparing notes and offering congratulations to those with impressive numbers. I felt rested, though desperate for a cup of coffee. I packed it up, made my farewells to the marathon stalwarts, then headed into Arizona City to join Ron for breakfast (coffee!) and a good long talk. A better way to end a star party would be hard to imagine.
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Comments [1]
03/29/2008, Tucson AZ
Seeing: P. 4
Transparency: (NELM) 4.5 (SQM) 18.54
Weather: comfortably cool, light breeze, clear.
Instrument: SVP8EQ
Eyepiece/filter list: 32mm Agena SWA, Paracorr, 21mm Stratus, 10mm Plossl, 2x Barlow.
I started the night near the end of the much publicized "Earth Hour." To judge by the appearance of the sky and the reading on the SQM, I'd say Tucson was not paying attention. Maybe next year.
While I hoped to make at least a token of progress on the AL double star and Messier projects, tonight was mainly about making sure everything was in working order for next week's Messier Marathon. The electric focuser has been slipping a bit, and I wanted to be sure that the adjustments I've recently learned are necessary maintenance with the gadget could easily be done outdoors, under red light. I also wanted to check out and work with the newly acquired Paracorr and 2" Agena 32mm SWA eyepiece. I managed these things, and in the process added two Messier objects and a double star to the above mentioned projects.
The first test for the 2" eyepiece was M45, which this time of year is getting a bit low in the west. But I wasn't looking for a perfect view, just reassurance that the slight narrowing of the field of view caused by the Paracorr would not prevent the eyepiece from showing the entire cluster. (The ability to do so is one of the criteria I set for this acquisition.) The presence or absence of the Paracorr did not make a clearly visible difference in the size of the field of view. There was a bit of restriction, but I can ignore it. A good thing, too, because while I'm not terribly sensitive to coma, this eyepiece (without the correction provided by the Paracorr) would be a huge disappointment. With the Paracorr in place there is a bit of astigmatism visible in the outer 10% of the field, with a touch of coma still present in about the same area. The way I view objects - on axis - I will not be troubled much by this. In the focuser with the Paracorr removed the performance was very poor, with coma beginning to show around the central third of the view and becoming horrible near the edge. The difference is that dramatic: with the Paracorr the 32mm 2" is a nice, low-price option for the Newt, while without the coma corrector the eyepiece would be pretty much useless.
Intrigued by the degree of difference I saw, I removed the 32mm Agena SWA and plugged the 21mm Stratus into the Paracorr. I've always been very happy with the Stratus, which has become something of a workhorse/finder eyepiece for me at dark sites. It's field of view just barely accomodated the Pleiades, but the quality of the view combined with the Paracorr was a pleasing surprise. M45 barely fit, but the stars at the edge were clearly focused, and not distorted at all. I found myself wanting to test these eyepiece/Paracorr combinations on M42, but the southwest sky was not quite dark enough, so I went on to other matters.
With the 21mm Stratus still in the Paracorr, I found and focused on M35. The slippage of the focuser was quite noticable, so I slipped the headlamp over my hat and applied the tiny hex key to the equally tiny (and barely visible) set screws. A small adjustment was all it took - problem solved. That done, I turned my attention to the open star cluster. This has always been a pleasing sight with the 21mm Stratus, all the moreso tonight with the Paracorr on the job. Oddly enough, for all of this I could not clearly make out NGC 2158, an object that has always been visible to me at least with averted vision. Perhaps the relatively poor seeing, combined with the sky glow to the west of me, concealed the more distant cluster from my sight. I made a sketch all the same, showing the cluster arranged in patches of moderately bright and relatively faint stars across much of the field of view. This is a rich enough cluster that I must admit that sketching it in a suburban location simplified that task. I've observed this one under dark skies, and the field would be simply intimidating to render using a pencil point! This is not, of course, any excuse for not giving it a try sometime in the future, but I am satisfied with the sketch I did tonight, for purposed of the AL project.
Since I was in Gemini, I decided to knock a double star off that AL list. The star in question, delta Geminorum, isn't exactly the widest double on the list, but is still well within the theoretical capabilities of the Newt. When theory bumps into seeing conditions, however, the results can be less than what I might hope to attain. I did manage to split the pair, from time to time. When the air steadied enough the split was obvious, if fleeting. The situation created by the seeing conditions was complicated by the nature of the double, meaning the closeness of the components and the significant difference in magnitude (about 3 for the main star, 8 for the companion). The companion was barely visible most of the time, due to glare from the pulsing and shimmering primary. When I could see it clearly the companion was a faint, pale blue spark beside the much brighter white star. The color contrast was just noticable.
I put the 2" SWA back into the Paracorr and pointed the Newt up at M44, the Bee Hive cluster. Even the 21mm Stratus does not provide a wide enough view to make a good sketch of the cluster possible. (At least, not so it would satisfy me.) The new eyepiece is a very different experience. Enough of M44 was in the field of view to make sketching it for the Messier Club worth my while. The Bee Hive, as revealed by the new eyepiece, is dominated by stars that occur in pairs and trios, with scattered stars that form a variety of parallelograms. This is still an object best appreciated with binoculars, but the view tonight was a very good one.
The sky was dark enough to make a look at M42 with the new eyepiece worth my while. And was it ever worthwhile! This eyepiece and the Paracorr paid for themselves when I took a look at the Great Nebula. The broad sweep of the nebula was visible, along with the star clusters to the north and the doubles to the south. It was a very pretty sight, and left me feeling pretty good about it all when I called it a night.
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03/24/2008, Tucson AZ USA
Seeing: P. 6
Transparency: NELM 4.5
SQM: 18.49
Weather: cool, calm, and clear.
Instrument: SVP 8EQ
Eyepiece/filter list: 25mm and 10mm Sirius Plossl; 6mm Celestron Plossl; 4.8mm TeleView Nagler; 2x Celestron Ultima Barlow.
I found myself faced with yet another evening of better than average conditions, and not enough time in which to do them justice. Rather than fall further into the bad habit of saying, "Why bother with an hour or two?" I set the Newt up in the back yard and made up a short list of double stars to pursue. In the end I bagged just three of these, but came inside at the end feeling it had been worth my while.
I decided to chase doubles that will soon be lost for the season, many of which are in the brighter southern part of my sky. Several came off the list immediately; I'd misjudged how low they would be, and they were either too close to the roof line of the house, or below it completely. The star 32 Eridani was the first I could work on, a star that proved a bit of a challenge to find in the bright sky. With the help of binoculars I managed to get it in view, using the 25mm Plossl as a finder eyepiece. In the 25mm it was just barely split. The best view for this one turned out to be what was seen in the 6mm Plossl; this became the sketched portion of the record. I did go so far as to use the 4.8mm Nagler, and while it was a nice view it did not change the degree to which the double was split. There was some difference in magnitude between the primary and companion stars, and an even greater difference in color. The primary was yellowish, while its companion had a soft grayish blue look.
As I was making a sketch of 32 Eridani a tiny satellite cruised through the field of view.
For some reason the Astronomical League lists beta Monoceros as a mere double star. Because of this I spent some time trying to make sure I was looking at the right star. It was less trouble to find than 32 Eridani, but still took some searching. In the 25mm finder eyepiece of the evening the star had a distinctly elongated, almost peanut shape, but did not split. I tried the 10mm Plossl and got a nice clean split, only now the companion star was the one with the peanut shape. Puzzled, I upped the magnification, using the 6mm Plossl. At this point all three stars were distinctly visible. I actually went inside to look up beta Monocerus in NSOG to reassure myself that this was indeed the correct star. I was not thorough enough in my pre-session research, and so missed that this was a triple star. And a very fine example of such a system, too! In terms of magnitude, there is a visible difference between the primary and its twin companions, but none at all between the companions. The companion stars are closer to each other than either is to the primary. All three stars are white in hue. The best view, and the one sketched into my field notes, came from using the 10mm Plossl and the 2x Barlow.
There was time for one more, if I could find the star in question; difficulties with my first target left me wary. But epsilon Monoceros was soon in the finder eyepiece and just barely split by the 25mm Plossl. When all was said and done, I settled on the 6mm Plossl for the record. There was a significant difference in magnitude, but the color contrast was a more subtle matter. The primary was on the warm side of white, and the companion had just a touch of yellow to it. It was a pretty pair, in that quiet way double stars sometimes have of showing themselves.
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