On November 16th, the sky was clear and, after a glorious sunset, atmospheric seeing promised to be mediocre but transparency was predicted to be superb. With no Moon in the sky, conditions were right to take the EVScope for another spin. I've now (separately) purchased the backpack that's sold with the EVScope; my rolling case, I suspect, my knock the telescope out of alignment. When I set it up this time, collimation was just about perfect. I made a couple tiny tweaks - again, this took seconds - and then rapidly achieved fine focus with the built-in Bahtinov mask. It was cold and I was exhausted, so I figured I would only take two ten-minute exposures of the Andromeda and Triangulum galaxies. Moments after the telescope slewed to Andromeda, I heard some rustling in the distance and noticed a dim orange glow, appearing and disappearing. Then the sounds of muttering wafted over on the breeze. It seemed I was sharing my park - and I had the disquieting feeling that I was being observed. After about eight minutes or so, I thought a third shadow joined the two in the distance, and then the rustling got closer. The conversation, it seemed, was definitely in Russian. Suddenly a flashlight turned on; there were three people, and they were walking directly towards me. I greeted them: "Hello? Hi!". At that, one of them exclaimed "oh my God!", and then all three of them darted to the side, behind a bush, and disappeared. The sounds receded into the distance. That was unsettling. Fortunately, after ten minutes the Andromeda exposure turned out nicely, considering the light pollution. Collimation and fine alignment really makes for much tighter stars and far better images, though I imagine things would be better still in superior seeing (and, of course, under a darker sky). Now it was on to Triangulum. It wasn't long ago that I managed to spot the galaxy with the FC-100DC, under darker skies some distance from DC. I noticed only a slight brightening of the sky, with averted vision, in what I could just perceive - or imagine - to be a spiral pattern. Clearly observing the galaxy now, from downtown, is a particular thrill. I don't know why, but Triangulum in particular has always captured my imagination. Maybe it's because it gets so little attention compared to the two giants of our Local Group of galaxies, or maybe because it's a face-on galaxy with distinctly knotted spiral arms . . . I'm not sure why, exactly. In any case, I find that the EVScope does a particularly good job on this galaxy (see above). And again, during the exposure I was in for a shock. With a loud thump and a lot of growing, a rabbit suddenly rushed right by the telescope, a fox in hot pursuit. The fox stopped short of my location with a snarl, then scampered - its little legs a blur - over a hill and behind a bush. Both fox and rabbit were no more than six feet from me. I couldn't wait to tell my four-year-old daughter in the morning. Anyway, after a few more minutes the Triangulum exposure was done to my satisfaction. I packed up the telescope, warmed my chilled fingers, and walked home. Suffice it to say, I've really started to enjoy the EVScope. A few days after my strange night with the EVScope, an ad appeared on AstroMart that forced me into hours of tortured thought (usually while attempting to get my one-year-old to sleep). Here was a Takahashi FC-100DZ, used only once and in pristine condition. As I've mentioned before, this year I've been tempted to swap my 100DC for a DZ. The DZ has better color correction and its optics might be marginally sharper, on average, though both improvements may be difficult to detect visually (I read many opinions, and they seem to differ). You can read a great breakdown of the relative merits of the four current FC-100 models here. I've resisted the urge to swap the DC for the DZ because, first, the hassle and expense seemed daunting, and second, the DC's weight is supposed to be lighter. The difference in weight, I concluded, outweighed (sorry) the marginal difference in optical quality. Yet the four-inch refractor is my most used telescope, and now I couldn't resist the urge to upgrade to maybe the finest refractor of this size ever made. So, I bought the DZ and sold my DC (along with some other stuff to make up the cost). I have to say, the comparison between DC and DZ surprised me in a few ways that aren't covered elsewhere. First and for my purposes most importantly, the weight difference between the two telescopes is scarcely noticeable. In the above pictures, you can see the DZ in a configuration for short-range, daytime viewing. However, to reach focus for astronomical viewing you must detach one of the couplings, and that makes the DZ noticeably lighter. It is then also more compact than the DZ when the sliding dew shield is tucked over the optical tube. Second, the most important couplings of the DZ do not screw apart but rather use thumbscrews and compression rings. You can also use that system to attach a diagonal, and I can't tell you what a difference it makes. I actually detest the Takahashi fetish for stacking screwable couplings in the visual back. The couplings, I've found, tend to stick together, and they're not wide enough to grip easily. It's easy to damage them (cosmetically) by applying too much pressure (I did as much to one of the DC's couplings). The new system brings the DZ in line with most other fine refractors, and it is just such a relief. Third, to balance the telescope - using just about any eyepiece - the clamshell tube holder must sit farther from the visual back than it does with the DC. This may seem like a very minor detail, but it provides more room for a red dot finder (RDF) just in front of the visual back. My Rigel QuikFinder RDF is now in a more comfortable position, and it's those little details that can make a real difference in the field. Fourth, the focuser is just a bit nice. Its knobs are metal - not plastic, as in the DC - and the feel is a bit smoother (though I did need to adjust the tension knob for my big Delos eyepieces). I sold Takahashi's two-speed focuser upgrade with the DC, and although I will no doubt miss the fine focus on the DZ, I didn't like how the two-speed add-on left some daylight around the gear housing. On the DZ, I'll stick with the stock focuser. That focuser, by the way, allows me to reach focus with all my eyepieces - something that was just out of reach for the DC. Finally, although the sliding dew shield is very smooth and easy to use, its tightening screw does leave a subtle mark on the optical tube that is noticeable when the dew shied is deployed. I wonder if the previous owner tightened the screw a bit too much, but I doubt it; I think this is just a natural consequence of the technology. It only matters if you're obsessive about the condition of your equipment - but Takahashi telescopes are so beautiful that they tend to bring out that obsession. Last night, and against my better judgement, I took out the DZ for the first time. I say "against my better judgement" because transparency was mediocre and seeing was poor. It's a recipe for disappointment to take out a new telescope in such conditions. I couldn't resist, but I did set up near the cathedral, closer to my house so I could hurry back if observing disappointed.
And did it? Well, a look at Mars did clearly reveal that the atmosphere would not be my friend tonight. And yet, I could plainly make out no fewer than three large dark albedo markings, along with that brilliant south polar icecap. Turning elsewhere, Rigel A and B were laughably easy to split in the poor seeing, and Orion was beautiful even before it emerged from the light pollution near the horizon. So could I make out an optical difference between the DC and DZ? Not after one night of poor seeing. Mars did seem a bit yellower than it does through the DC, and certainly I could detect absolutely no hint of false color in or out of focus. I'm excited to study the Moon, for example, on a really good night. Yet I don't expect a large or even a plainly noticeable difference. I bought the DZ primarily so I could be absolutely sure that the optical quality of my most-used telescope would never hold back my observations - and so that I would never wonder what something would look like with a slightly better telescope of the same design. It's a tiny thing, but after a while tiny things start to matter a whole lot in amateur astronomy.
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We've enjoyed maybe the best stretch of clear nights with good seeing that I've experienced since moving to Washington, DC, and I was out nearly every night with a telescope in hand. Between work, childcare, and observing, I had no chance to update this blog - but now it's raining, and I have an hour (but just an hour) to relax. Roughly two weeks ago, I spotted a Takahashi FS-102 for sale on Astromart. Amateur astronomers will know that this is a four-inch refractor with a well-earned reputation for exceptional optics. It's been replaced by the Takahashi FC-100 series, and I already own a telescope in that line. But the FS-102, while much bulkier than my 100DC, does better at longer wavelengths. And in Mars-watching season, that's what I convinced myself I needed. Although the FS-102 was supposedly in pristine condition, when it arrived I was dismayed to discover that the lens cell was loose and the tube was covered - I mean covered - with scratches. Luckily, the owner was mortified when I informed him, and I received a (nearly) full refund. I now had some cash to spare, and at just that moment a new copy of Sky and Telescope arrived. A favorable review of the EVScope convinced me to give that telescope another chance (see a previous entry for my first impressions). Maybe the buggy version I owned before had unfairly soured me on the product? It did, after all, offer me a chance to observe nebulae and galaxies I would otherwise never have a chance to see from the city . . . . After it arrived, I bundled the telescope into a suitcase and rolled it along to my nearby park. After I turned it on, it just about instantly figured out where it was and slewed (quietly) to any object in the sky, like magic. Clearly, I'd been sold a glitchy version the first time around. This was more like it! And when I tapped on "enhanced vision" (I describe the technology in a previous entry), the effect was really satisfying. After a couple minutes gathering light on the Andromeda Galaxy, for example, dust lanes I'd previously spotted only with averted vision clearly snapped into focus. So, how good are the views? Well: although I managed to achieve fine focus, I think I'll need to collimate the telescope when I'm next out. Stars are not exactly pinpoints, as these images attest, and that's also caused by a tendency of the telescope to move too much while it's gathering and stacking images. There's more noise in the pictures than I'd prefer, and after getting used to my wonderful TeleVue eyepieces, the view through the EVScope's "eyepiece" is really cramped. It's like looking through a tunnel. More importantly: no, seeing an image through a grainy screen is just not at all the same as seeing it through an optical eyepiece. An optical telescope feels like an extension of the eye; not so the digital EVScope. But damn, it's cool to see galaxies shimmer into view on my iPhone screen. It's simply true that I can see things now that I never would have imagined seeing before, and isn't that what this is all about? I mean, the Triangulum Galaxy from an urban sky . . . are you kidding me? I'm still learning how to use this technology, and pictures I've seen online tell me there's plenty of room for improvement. Still, I've noticed that the images look much more spectacular in the app, while I'm in the field, than they do after I get home. Certainly they pale in comparison to even half-decent astrophotographs made with dedicated gear. Now does the technology always work seamlessly. Just a couple nights ago, I had to restart the telescope and reinstall the software before I could get the enhanced vision mode to work, and by then I'd already shivered outside for about 30 minutes. Some objects also look immeasurably better through my optical telescopes. The EVScope is just about useless for lunar and planetary views, and stars look like ugly blobs compared to the beautiful diamonds they resemble through my refractor. Yet what the EVScope does so well is find that sweet spot between visual observation and astrophotography, and it does so in an integrated package that's usually a pleasure to use. No, I never had the thrill of seeing something with my own eyes - the thrill I've described often in these pages - but I certainly did get a deep sense of pleasure when I glimpsed the Whirlpool Galaxy from the city. One virtue of the EVScope is its weight. If I stuff the EVScope into the suitcase I used for the APM - which, admittedly, does seem to mess with its collimation - then I can easily sling my Takahashi 60Q over my shoulder (and wedge its tripod in the suitcase). I've now used the 60Q twice, including once in the early morning, with the EVScope gathering Orion's light. I have to say: I was more than a little stunned by its quality. To my astonishment, the Moon through the 60Q really didn't look any dimmer than it does through the TV 85, and details were equally sharp. Here are three images I took of the Moon over the last week, with the 60Q, the FC-100DC, and the APM 140. A reminder: the 60Q has an aperture of about 2.5 inches; the 100DC of 4 inches, and the APM of 5.5 inches (these are big differences for refractors). The optical quality of each telescope is roughly similar, though I'd say the APM shows the most false color, and the 60Q the least. That's the 60Q on the left, and the APM on the right. The comparison isn't quite fair; seeing and transparency differed on each night - it was average when I used the APM, and decidedly better than average when I used the 60Q and 100DC - and while the smaller telescopes had fully cooled down when I took these images, the APM in my judgement had not. Still, it amazes me how slight the differences are. I have a new phone, by the way, with a much better camera, and I think it shows. These pictures were taken after the APM had fully acclimated, and I think it's fair to say that now the aperture difference is more easily visible. There's a deeper and more richly textured quality to these images than there is to the 60Q closeup above. Yet it always takes me aback to realize that, when telescopes are of similar quality, differences from night to night on bright objects - the Moon especially - owe more to atmospheric conditions than anything else, including aperture. It's different for dimmer objects. I can usually see at least five stars in the Trapezium using the APM, for example, but I've rarely if ever confidently spotted a fifth with any other refractor. Mars was full of detail when I observed it with the APM - wow that south polar cap looks bright and sharply defined right now - but I found that it, and every other bright object, was surrounded by a bright halo that night. This seems to be a common and very annoying optical effect in the skies of Washington, DC. On two nights with the 100DC, however, I had no such problem. Dark albedo markings were wonderfully detailed, and I spent easily an hour both nights just enjoying the view. It's a little sad to think that every night brings us a little farther from the red planet, but the view should dazzle for months to come. One last note. My first night out with the 100DC over these past two weeks was November 3rd. I suddenly resolved to stop doom scrolling and instead do something that distracted me. But what a sinking feeling I felt, walking bewildered to the field, with panicked screams - yes, screams - echoing around me. I walked out on the 4th, too, and the mood was lighter. Then, on the 7th, while playing with my kids in the very spot I usually set up my telescopes, came the good news: the networks had called it for Biden. I'll never forget the scenes of spontaneous joy on the streets: the bells ringing, cars honking, crowds cheering. We may be in for some very dark months this winter, but that was a moment I'll long remember. After selling my EVScope recently - you can read more about that choice below - I sold a few other items and wound up with a nice chunk of change. I started feeling a familiar temptation, one I've described often in these pages. Should I buy a big telescope that, yes, wouldn't cool down quickly enough to use outside of summer, and yes, might struggle with dew or collimation, but - but! - if conditions were just right, could show me more of the universe than my refractors currently reveal? One option after another came to mind as I struggled to settle my one-year-old at night, and one after another I knocked them down. Visions of what I might see with a much bigger telescope clashed with visions of that telescope gathering dust in my closet while I walked out the door with another small refractor. The truth is, I have to walk too far and observe too quickly for anything other than a refractor to make much sense (except perhaps a Hubble Optics reflector, but I worried about setup time). In the end, I decided to double down on what I already have, and add a little variety to my refractor lineup. I really wanted a telescope that's even more portable than my TV-85, for nights I'm feeling tired, want to go further afield, or don't have enough faith in the atmosphere to haul out a bigger instrument. And I wanted a refractor that's a little better in red wavelengths than my FC-100DC, and maybe just a bit more attuned to planetary observation. No major leaps, then, but a bit more versatility and a bit more variety. My first purchase was a Takahashi FS-60Q. I found what seemed like a good deal and couldn't resist pulling the trigger. The 60Q screws in half, so it fits neatly in a small backpack with my VAMO traveler mount. It even comes in two formats: a tiny, do-everything version with a very short or "fast" focal ratio, and a long "Q" version that's "slower" and has much better color correction. That's the version I'll use - screwed in half, as I carry it on my back. When the telescope arrived, the optics were in perfect shape but the body had a couple tiny nicks - imperceptible at first glance - and the dust cap didn't fit quite as snugly as I'm sure it once did. What's worse, I quickly found that I needed a long list of expensive accessories to actually use the telescope. After a couple weeks and a lot of headaches, I finally had everything assembled and ready to go. It was a cold night with below-average seeing: exactly the kind of evening that didn't seem to justify dragging out a bigger telescope. The weight of my whole setup was almost laughably light as I excited my building; I could barely feel it at all. I could get used to that . . . . I found that same spot next to the church where I'd set up my APM a week or so ago. It took me just a couple minutes to unpack my gear, although I have to say: screwing the little telescope together is an extra step that can be a bit awkward in the dark. The sounds of traffic were also a little too close for my liking, and I wished I had walked on down to our nearby park. Yet it was late, and this was so much better than nothing. Mars was now right at opposition, and wow did it even look big - even through the little telescope. To my delight, both dark albedo features and the south polar ice cap were immediately obvious on the planet, and the seeing didn't seem that much worse than average (owing, perhaps, to the smaller aperture of the telescope). I could make out Mare Cimmerium, clear as day, and I think maybe - just maybe - the long, thin outline of Hyblaeus. The Curiosity rover, the Insight lander, and even Viking 2 were all in the picture, in a more or less vertical line across the planet. After about half an hour of ogling, I packed up. The view was much dimmer than it is through my bigger refractors, but the detail I could make out was truly impressive for such a little telescope. The one drawback: I can't reach focus with any of my Delos eyepieces using the telescope. I suppose that's okay; they're really too heavy for a really portable setup. Then, last night, I returned to the church with my FC-100DC. Atmospheric seeing promised to be better than average, but it was immediately obvious from the halos around streetlights that transparency would be anything but. This time, I nearly convinced myself to keep walking to the park, but again it was cold, I was tired, and I wanted to go to bed on time. What a joy it's been to observe Mars high in the sky in the evening, rather than the (painfully) early morning!
Strangely, I happened across much the same region of Mars. While the planet was a good deal brighter than it had appeared through the FS-60Q, the transparency was so bad that I spotted only the tiniest hints of additional detail (usually, it's the seeing that limits planetary observation). Once again, I enjoyed the view for about half an hour, watched a deer walk daintily across the sidewalk, and then packed up. Hard to believe that I can now get six hours of sleep after observing Mars! Opposition! What a word, for Mars observers. Earth is directly between Mars and the Sun in exactly one week, and it's in a part of Mars's orbit that takes it especially close to our planet. We won't get a view like this for 15 years or so, and we haven't had one like it since 2003. Technically, Mars was a little closer in 2018, but as I recall it didn't get very high above the horizon then for Northern Hemisphere observers, and a global dust storm - more likely when Mars is relatively close to the Sun - thoroughly spoiled the view. At the time, my telescopes showed only a fuzzy orange ball, with just the faintest hint of dark albedo features (and that was probably my imagination). I resolved then to be ready for 2020, and I certainly have been. This week, I explored the planet with my Takahashi FC-100DC and APM 140, and wow: what a view. I should begin by saying that I also observed Mars in single-digit (Celsius!) weather on the morning of September 22nd, but also the seeing was forecast to be average, the transparency of the atmosphere left much to be desired. There were odd halos around everything: street lamps, the Moon, and certainly Mars. I could only make out four stars in the Trapezium with the APM, and albedo features didn't pop on Mars as they can when the atmosphere is stable and clear. When the sky cleared again on October 4th, I decided to take my 4" Takahashi to the field. Mars rises early enough now for me to step out in the late evening - just before midnight - which typically allows me to sleep more restfully (albeit still for only four or so hours). This time, transparency was a whole lot better, but seeing was about the same: not terrible, but by no means good. Albedo features were stark and obvious on the planet, however, and I wished I'd taken a sketch pad. I was unhappy with the iPhone drawings I attempted to take on other nights, so I opted not to draw one of those - maybe a mistake, but it did give me more time to drink in the view at the eyepiece. The Moon had a hint of that "watery" look it can take on when the seeing is mediocre, but still: I had a nice long look at Mare Crisium at lunar sunset. Jupiter and Saturn had long since set, and I had a pang of sadness: I'm unlikely to observe them for a good long while. Mars will make up for it! Then, tonight, the seeing promised to be above average. I'd hoped to observe in the evening again, but unexpected clouds ruined that plan. By 3 AM the sky had cleared, and out I walked with my APM 140. To my alarm, Mars was already lower in the sky than I'd anticipated, and I feared it would be lower still by the time I arrived in my preferred observing site. I hadn't walked far when I noticed a dark alcove beside a church I frequent, and it occurred to me that it would afford a great view of the southern sky. So, I abandoned the field I normally visit for that alcove: a high risk gambit, since the field is a sure thing and it seemed entirely possible that there might be currents from nearby buildings to ruin this spot. Worse: the church is right next to the National Cathedral, and I worried: could security kick me from the grounds? But no, this time it all worked out. I found a nice corner to settle down, and when I turned the APM to Mars it was full of wonderful detail. The entire southern hemisphere of the planet seemed dark, relative to the rest, with spectacular, linear features that helped me realize how nineteenth-century observers could have imagined a network of canals on the planet. The south polar cap was remarkably bright and clearly defined, and I could just - just - make out the white clouds of the north polar hood on the limb of the planet. Mars reaches its closet approach to Earth next Tuesday at 10 AM EST: a scant 62,069,570 kilometers (by astronomical standards, a stone's throw). It was quite strange to see the planet so big and bright, entirely illuminated by the Sun. I felt it was almost too bright for the APM, strangely enough, at least at 217x (the highest magnification I felt I could use with a manual mount). Still: what an unforgettable view. The waning Moon was nearly at zenith, and in good seeing it also provided a spectacular view. Yet because I wanted to keep switching to Mars, I didn't adjust the height of the tripod - and that made for a very uncomfortable lunar viewing experience (painful, in fact, because of a worsening neck and back injury). I captured some quick pictures without being able to fully stabilize my old phone, and they actually turned out a bit better than I'd hoped. A testament to the capabilities of the APM in an accommodating atmosphere.
By next week we will be on the downswing of this year's opposition, and it already saddens me to think how long it will be before we have a similar view. What will the world look like then? With how quickly things seem to be changing - often, it appears, for the worse - it seems impossible to guess. With any luck, I'll still have this blog - and I'll still have a telescope as good as the APM 140. To say I was tired after my last morning out is an understatement. There's nothing like 16 straight hours of work and childcare after a three hour night's sleep. Yet when the forecast called for better-than-average seeing and transparency on another clear morning, I had to go out again. After all, it'll be a while before Mars looks this good. This time, however, I took my Takahashi FC-100 DC and my lightest tripod; I was still a little sore from hauling the APM. Conditions were just about the same this morning as they had been on the sixth, and that provided a nice opportunity to test how close the view through a good 4-inch refractor can get to that of a 5.5-inch (the APM). In a word (okay two words): pretty close! The Moon dazzled with detail, although I definitely saw finer features - especially those rilles - with the APM. Mars was wonderfully clear, with dark albedo features obvious but maybe a bit less dark than they had been through the APM, and the south polar ice cap much dimmer. Orion and the Trapezium were wonderful, but I could only clearly see four stars in the Trapezium - with a hint of the fifth, "F" star. You could drive a truck between Rigel A and B, but maybe a slightly smaller truck than you could with the APM. The Takahashi is just a fantastic telescope. I set out to observe Mars, and indeed I observed the planet for a good long time. Two years ago, during the last opposition, I dreamed of exactly the views I've had this year. Once again, I tried sketching the view on my phone, but it's become clear that I've reached the limit of what's possible with that technique. Next time, I'll bring sketchpad - but still, it's nice to know what I've seen. I found that the steady atmosphere easily permitted a magnification of around 250x, which is rare in these parts - and better than I enjoyed on the sixth. Although I spent a lot of time on Mars, I found I kept returning to the Moon. There's nothing like the gloriously detailed lunar views a fine refractor can reveal in good seeing. Features visible around the terminator were especially interesting tonight, with plenty of tiny craters glinting at local sunset, and some really interesting, rectilinear scarps (or so I decided; I'll have to look this up later).
So, another great morning - but it'll take me a few days to recover this time. After two weeks of rainy, stormy weather, the skies cleared over the last two nights, and seeing conditions were, remarkably, better than average. On the evening of the eighth, I marched out of our apartment with my Takahashi, focal extender installed, to have a good look at Saturn and Jupiter. Both are now fairly high in the evening sky, beginning at around 9:00. After a fifteen-minute walk to my favorite park, I was ready to go. Jupiter, it turned out, was a little disappointing. I did manage to catch some tantalizing glimpses of complex details in the planet's belts, including one enormous ruddy patch in the north equatorial belt. But, on the whole, the colors and contrast were a little muted from what they can be. Atmospheric transparency was a little lower than average, I thought, so maybe that was to blame. Or maybe the APM 140 has spoiled me. When I switched over to Saturn, however, I was rewarded with one of my best-ever views of the planet. The Cassini Division stood out sharply along the entire ring system, and the thin black shadows visible behind the rings and on the rings, behind the western limb of the planet, were perfectly crisp. I thought I could make out no fewer than two grayish cloud belts - normally, I can clearly see just one. I admired the beautiful planet for a good long time before packing up and heading home. Then, on the morning of the 10th, I set out at 3:30 AM to observe the Moon and Mars. It's amazing what we do to ourselves, as amateur astronomers, to pursue our passion. I can never sleep well when I know I'll have to observe in the early morning, and on this night I'd had maybe a couple hours of sleep. Would it be worth it? As I left my building and set out for the park with the Takahashi, I noticed two things. First: the Moon and Mars were really high in the sky! Second: there was space in my building's illuminated "back yard" (as my daughter calls it) to set up the telescope. Why wouldn't I just do that and save myself the walk? I was awfully tired, after all. I went for it, and I can't recall making a more disastrous observing decision. After seeing up in one corner of the area, the sprinklers, which had been silent, suddenly started up exactly where I was sitting. In a panic, I grabbed what I could and rushed to another part of the yard. Nothing was damaged, but my eyepiece - a TeleVue Delos - did fog up completely. Ugh. Now I was forced to set up directly under no fewer than four bright lanterns. Maybe it wouldn't matter, I tried to convince myself. Oh, it would. Stray light kept entering the eyepiece, spoiling the view with ghostly reflections. Both Mars and the Moon also had a halo that's not usually there - partly because of the mist rising from the sprinklers, I decided. I also decided that stray light washed out some of the contrast on Mars. And what a pity, because a look at the Moon quickly convinced me that seeing was as good as it has been all year. I'm certain I made out at least a couple craterlets in the crater Plato - a sure sign of excellent seeing (and an excellent telescope). Mars was disappointing, only because it was so obvious to me that I would have seen far more had I just walked to that park. Still, dark albedo markings repeatedly shimmered into view, and the southern polar cap was obvious - if a good deal smaller than it had been earlier in the year (or have the bright clouds that make up the southern polar hood dissipated?).
Then the sprinklers turned on near me - it turns out I hadn't escaped them entirely. Why not soak pavement during the entire night? It's not like we're in an ecological crisis or anything. Once again I packed up, this time for good. All in all I was happy to have had a good look at the Moon, and grateful for the lesson - don't use the backyard! - well in advance of Mars's opposition this year. Still, after sacrificing so much sleep I had hoped for a better view of Mars. Next time! This weekend, we travelled to the Shenandoah Mountains with our "bubble family" for a much-needed getaway from Washington, DC. It took a little negotiation - even a short trip with kids requires a lot of luggage - but I eventually received authorization to stow a telescope in the trunk. There wasn't much room, so the telescope had to be small, and that left two options: the TV 85 or the Takahashi FC-100DC. I decided I wanted the extra reach of the Takahashi, so I unscrewed its focal extender - shortening and lightening it - and then found a way to make it fit with my lightest tripod. To my delight, our cottage turned out to have two balconies, both isolated from surrounding houses, and was just enough of a clearing in the trees to reveal a part of the night sky. That part, I soon realized, could not have been better placed: it would reveal the Ring Nebula and the Hercules Globular Cluster in the evening, and the Andromeda and Triangulum galaxies in the morning. Even better: the forecast called for clear skies on both nights we were there. What are the odds? On the first night, I stepped directly from my bedroom to the cottage's narrow, second-floor balcony. The air was alive with the squawking of birds and the buzzing of bugs. Luckily I brought plenty of mosquito repellant - although it was hard to forget about the legions of spiders spinning webs just overhead - and wow: what a night sky! Bortle 4, by one classification scheme; yellow or maybe green by another. It was, admittedly, not perfectly dark, but to this city slicker it was nothing short of a revelation. It's been so long since I've seen the Milky Way - but there it was, clearly visible. There were in fact so many stars that it was hard, for a moment, to pick out the constellations! Oh, what I've been missing in DC. To my surprise, Jupiter and Saturn both turned out to be high enough to view from the upstairs balcony. Saturn was beautiful, but I've had better views from the city. Jupiter, by contrast, was so clear and full of contrast - and, lucky me, I had tuned in just on time to see another shadow transit! To think that I'd never seen one before this month. Callisto, it turned out, had just finished traversing the planet, and its shadow was still in the clouds. The shadow seemed a bit more distinct - a bit more clearly round - than it had been on the surface of Jupiter with the APM 140 on the 10th, but I found I couldn't increase the magnification beyond 123x without the view breaking down. To my surprise, I also found that a new Delos 6mm eyepiece presented a clearly better view than my trusty Nagler 3-6mm zoom. Next, it was off to deep space. It has literally been decades since I had a telescope under a reasonably dark sky, and so it was such a pleasure to simply trawl through the Milky Way at low magnification, admiring the knots and clusters of random stars. Every patch of the galaxy, every view, resembled an open cluster from urban skies. Incredible. There are, I realized, deep space objects that look better under dark skies - that is, more of the same - and those that look different. The Ring Nebula, I realized when I finally look that way, mostly looks better. I could easily make out a ring without using averted vision, which I can't do with anything smaller than the APM 140 in DC. Yet I could also make out subtle nebulosity within the ring - a first for me - and the ring didn't look quite as round as it seems in the city. The Hercules Cluster, however, looked completely different: less a fuzzy ball and more an explosion of innumerable stars, textured and complex right down towards the center of the cluster. When I saw textured, I mean it was almost as though someone had sprinkled especially dense clumps of glitter haphazardly over a page already covered with a thinner dusting. An unforgettable sight. On the following night, I decided to sneak out in the morning, this time on the bigger, first-floor balcony so I could see more of the sky. I never have much time with how little my son sleeps, but I hoped to get a good view of two huge deep space objects whose surface brightness is just too low for urban skies - the Andromeda and Triangulum galaxies - before catching a glimpse of Mars.
Andromeda was impressive: a bright, fuzzy nucleus (of course) and a subtle but immense disk, stretching out of view even at 25x. I thought that maybe - just maybe - I could make out a dust lane after around 15 minutes of peering, but that might have been my imagination. At last I tore myself away from the view and started scanning for the Triangulum Galaxy, which I've never managed to spot before. After about 15 minutes I tracked it down, and wow - was it ever subtle. I could make out its pinwheel shape using averted vision, and that was incredibly special to me. At last, Mars became impossible to ignore. Snapping in the 6mm Delos I was treated to an absolutely spectacular view of the planet at 123x, featuring that southern ice cap, of course, surrounded by a ring of remarkably dark dunes, and the unmistakable peninsula of Syrtis Major Planum. I have never had such a detailed view of Syrtis Major, and what timing: the Perseverance rover will soon blast off to land at Jezero crater on the border of the region. To be honest, this view alone exceeded my wildest hopes for the Mars opposition of 2020. Amazing to think that the planet will only seem bigger over the next few months! Yet just as on the previous night, although the view was full of contrast at 123x it broke down when I pushed the magnification much further. I had high hopes for 185x with the Nagler Zoom, but no dice. After a while, it was time to pack up. I was sorely tempted to look at the Pleiades, then just wheeling into view, but I had to be ready in case my son woke up. I couldn't complain, of course; together, both nights were nothing short of unforgettable. I now know: there's nothing better than a fine telescope under dark skies. With regards to the rest of my setup, I was really impressed with a new purchase: that 6mm Delos eyepiece. Beautiful contrast, incredibly easy on the eyes, and a nice field of view. The 30mm TeleVue Plössl was less impressive - actually, it's long been my least favorite eyepiece in my Plössl collection. Stars seem a little stretched out away from the center of the eyepiece; at first, it's like they're not quite in focus, and then, towards the edge of the view, they stretch out into miniature arcs. I think I might need another kind of eyepiece for beautiful wide-field views under dark skies. All in all, a memorable trip, and a welcome relief from these COVID times. The good times keep coming! Another clear morning, with average seeing and above-average transparency. Astronomy and my toddler have been costing me sleep recently, and deep down I knew it wasn't a good idea to head out in the wee hours again. Yet there I was, waking up at 2:30 AM, gulping down four cups of coffee, and slipping out the door with three big bags. My cat watched me go with a knowing look. When I got outside, the night seemed nearly perfect. Not a single cloud in the sky - now that's rare - and the stars seemed remarkably steady. Mars was a brilliant red near the half-Moon; it's getting noticeably brighter, it seems, with every week. The temperature was perfect, and a gentle breeze made it even better. As the Earth warms, I figure, most of us will be spending more time walking in the night. I guess I'll be a veteran. When I got to the park, conditions somehow seemed even better. I couldn't see the Milky Way, of course - not in these urban skies - but the sky did seem unusually full of stars. Then, as I unpacked my trusty Takahashi refractor, it suddenly hit me: I'd left my stool at home. A cascading series of problems followed. I'd taken my little Report tripod, which can usually hold the Takahashi okay, but only when not fully extended. Well, I would have to extend it all the way without a stool, and even then I'd have to bend over a little to use the eyepiece - let alone the red dot finder. A pleasant early morning under the skies suddenly seemed a lot less fun. My worst suspicions were realized when I turned to Mars, now high above the eastern horizon. The tripod wasn't up to the telescope, and the view took a full four seconds to stabilize when I nudged the planet into view. That's an especially big problem because I don't currently have an eyepiece with a big field of view, so I have to keep nudging and nudging - which means more and more wobbling. There was so much wobbling, in fact, that I hard time perfectly focusing the telescope - a consequence, in part, of the Takahashi's lack of a two-speed focuser. Craning over my eyepiece, I suddenly felt let down by my equipment, for the first time in months. If only I'd brought that stool! What's worse, the seeing turned out to be surprisingly uneven. It guess that breeze was messing with the view. Admittedly, the view of Mars would have thrilled me a month ago: there was the southern polar cap, bordered (if memory serves) by dark dunes, and there - in fleeting moments of atmospheric stability - a delicate latticework of dark albedo features, spidering up from the pole. And yet, on the whole it was all a bit blurrier than I expected. The Moon was impressive, with gloriously crisp detail around Plato in particular. I thought I could maybe - maybe - make out a few craterlets, but it was hard to be sure with the view wobbling, my neck aching, and my knees buckling.
When I turned south to Jupiter and Saturn, I was shocked - for the opposite reason I had been just a day and a half earlier. Both planets were almost void of detail, the view entirely washed out by terrible - not just bad, terrible - seeing. I hastily turned back to the Moon and tried not to remember the view through the APM. After a while, Venus rose to the northeast, a glorious golden crescent very near blood-red Aldebaran. It was nice to see the Pleiades again, rising over the trees. I suppose it won't be too long before Orion makes it reappearance in the morning sky. A bright comet, NEOWISE (C/2020 F3) is visible to the naked eye just before sunrise - a sight we haven't had, I think, since PANSTARRS (C2011/L4) in 2013, and Hale-Bopp (C/1995 O1) in 1997. Unfortunately, I couldn't stay out long enough to see it. I fervently hope it survives its pass by the Sun so I can catch it in the evening sky within a week or so - clouds permitting, of course. I walked home knowing it would be a very long day with very little sleep. Had it been worth it? If only I'd brought my stool, then certainly. But now . . . at least I'd gotten another good view of Mars. It's hard to imagine what it will look like in just a few months! Rocking a fussy baby is a dangerous thing. The mind latches on to anything that can distract from the crying, and for me that means telescopes. Could I really use my Mewlon 180, I wondered lately? The telescope is beautiful, but it takes at least an hour to cool down - about as long as I often have to observe. And would I really feel comfortable collimating it in a park? Could I even haul it to a park in the handsome but bulky carrying case I bought for it? The answer to all these questions, I ultimately decided, was no. At the same time, I happened across a new telescope model: a 140mm refractor made by a German company, APM. At just under 20 pounds, this telescope is remarkably lightweight for a 5.5" refractor, and because it's a doublet - meaning it has two lenses - it cools downs quickly. Color correction is also excellent - maybe not quite as good as my Takahashi FC100, but on par with my TV 85 - and a sliding dew shield means the whole assembly is quite compact. Quality control is so good that the telescopes can ship with strehl reports, meaning you know exactly what effect unavoidable wavefront aberrations will have on image quality. The price, meanwhile, is unbeatable for a big apochromatic refractor. I couldn't help but think that the APM would work much better for me than my Mewlon, especially as I've gotten used to those pinpoint refractor stars. Once the idea was in my head, as usual, I couldn't shake it. I sold my Mewlon and a few eyepieces - including my cherished Ethos - then bought a rarely used, second-hand APM with an unusually high strehl of 0.958. To my surprise, the big telescope rides quite easily on my AYO II mount. I had been told that the mount can't quite handle refractors with similar apertures, such as the TEC 140. But if I balance the refractor just right, it does fine - provided I don't use a heavy eyepiece. Which, hey, I had to sell to buy the telescope anyway. Although I promised myself after June 9th that I'd only take a telescope out in the early morning if the seeing seemed above average, by July 1st I couldn't wait any longer. Both seeing and transparency promised to be below average on the morning of the 2nd, but the sky was clear and I wanted to test the refractor. I went to bed at 10:30 PM, woke up at 2:30 AM, and was out the door at 3:05. I'd bought a large soft case to haul the telescope and all my equipment except my mount, and it certainly made it much easier to walk the 15 or so minutes to my new favorite observing site. When I got there, however, my arm was nevertheless ready to fall off. This urban observing location is really special: screened by bushes in a large park that I have permission to use at night. As on the 9th, I was surrounded by rabbits and fireflies, and by 4 AM a cacophony of birds started calling all around me. The nearby trees are alive with noise - not bird calls, but animals moving through them. An army of squirrels? A flock of pterodactyls? Either way, it's a memorable experience being out there in the early morning. Turning to Mars, the image was clearly brighter than what I observed through the FC-100DC on June 9th, but also softer with a bit more light scatter. Nevertheless, that southern polar cap and some delicate dark albedo features were clearly visible. Switching to Jupiter and Saturn, it was clear that poor seeing and to a lesser extent transparency, not the optics of my telescope, would limit my morning views. Both planets had more color than they do through my Takahashi, and I could see a whole family of moons around Saturn - always a thrill. Even at high magnifications, the view remained bright - another step up over the Takahashi. Yet I couldn't really push past 100x and still see detail; the seeing was just not good enough. Still, the great red spot was as obvious as I've ever seen it. I wanted to have a look at the Ring Nebula to compare the light gathering capacity of the APM to my other refractors. With so much light pollution in the muggy sky, the nebula still seemed faint. But I could clearly make out a ring without using averted vision - a first for me. Then, at around 4:15 AM, I noticed a bright light on the eastern horizon. Was it a plane? Or could it be Venus? I had a look, and yes - there it was, a delicate golden crescent. I've never seen Venus look so beautiful; a mesmerizing sight that defied all my iPhone attempts to take a picture. Walking back was another huge chore, and when I returned I noticed that the wheels on my case already had some wear and tear. Still, I thought the telescope acquitted itself very well. The only false color I detected, I think, was a function of seeing. Stars were, of course, pinpoints. The view was noticeably brighter than it is through my Vixen - about as bright as it was through my dearly departed C8, I figured. Thermal acclimation was nearly instantaneous. The mount was sturdy, with vibrations at well under two seconds. This telescope is a keeper. On the evening of the 2nd, I realized that the sky would be clear again on the morning of the 3rd - except now the seeing and transparency promised to be average. Could I really function for a second day on four hours of interrupted sleep? Yes, I decided I could - and there I was again, in the park by 3:30 AM. This time I brought my Takahashi. I didn't have the energy to lug out my APM on so little sleep, and I wanted to compare the view through the FC-100DC with what I'd had with the APM. Mars was, once again, my first target. I had been a little disappointed with the view of Mars through the APM, although to be honest I would have been blown away had it not been for that magical morning on June 9th. Now, using the Takahashi again, I realized that the view on the 9th was a function of good seeing and good transparency - and a great little telescope, of course. The view on the morning of July 3rd was similar to what I'd had using the APM on the 2nd, albeit less bright and with a bit less scatter (possibly owing to better seeing). The south polar cap was easily visible, and some dark albedo features too - a fine view, but not comparable to what I saw on the 9th. When I turned the telescope south to Jupiter and Saturn, I was surprised: the seeing in that part of the sky was actually worse than it had been on the previous morning. Jupiter in particular was a hot mess, with nothing visible aside from the most obvious belts and zones. I could just make out the Cassini Division on Saturn, and I actually got some half-decent iPhone photos. Saturn photographs much better than the other planets largely because it's fainter. My phone washes out all detail on brilliant objects on a black background, so Jupiter especially almost always comes out as a bright white ball - except in those especially blurry moments, while taking a video, in which the picture just passes into or out of focus. In general, views of Jupiter and Saturn were worse using the Takahashi than they had been with the APM, but a lot of that comes down to a slight difference in seeing. I would say that, with the focal extender, the Takashi probably gives slightly sharper but less colorful and somewhat dimmer views. With that said, the difference in brightness on the planets was less than I expected; the Takahashi puts up a hell of a fight against any telescope, it seems.
Turning to the Ring Nebula, the picture was very different. In subpar transparency - the forecast lied - the nebula was only barely perceptible at all. I needed averted vision to see a ring, and then again - just barely. I guessed that the view with the APM was twice as bright, a gigantic difference, of course, when it comes to observing deep space objects. Once again, Venus loomed on the horizon when it was time for me to start thinking about packing. Once again, the view was glorious - and the iPhone washed out all details (ditto for Mars). Oh well - I took a shot anyway, and now it's on this website. Somehow, even terrible pictures help me remember the wonder. Dodging crowds of rabbits, I made my way home. The lack of sleep hurts, but I'll cherish these early morning memories. And I sure am happy to have another telescope in the fold. Washington is a feast-or-famine city for amateur astronomy. Clouds and bad seeing can endure for weeks - even months - with little relief, and then, suddenly, the weather clears for a week. When that happens, I've learned to take advantage of it - no matter how tired or distracted I may be. So when the sky cleared last week, I was ready. Unfortunately, the first couple nights were marred by bad seeing. But the last two nights may have been my best since I started this hobby, many years ago now. On night one - on the seventh - I hauled my Vixen 115SED to a park about a ten minutes' walk from my home. With its various upgrades and attachments - including the diagonal - the Vixen weighs just under 15 pounds. My larger tripod - a Berlebach - weighs around 12 pounds. Everything else probably weighs about as much. Walking ten minutes with all that gear - in three big bags - is about all I can take. But I made it, and after thoroughly dousing myself with mosquito spray, I walked towards the center of the park. There, I found a depression screened with bushes: quite possibly the best observing site I've encountered in a city. As I unpacked, I found I was surrounded by rabbits. Over the next two hours, they would routinely hop by, some no more than six feet away. I could see the flash of their white tails bounding along from time to time. My attention, however, was elsewhere. The Moon would rise only after I had to walk home, which meant that conditions were ideal for deep space observing. Of course, while seeing was pretty good, transparency was much worse, and at the beginning of the evening banks of high-altitude clouds seemed to obscure exactly what I most wanted to observe. Still, even then I had a good look at some particularly beautiful and bright stars: Arcturus, for example, glowing like an ember in the dark. Whenever I take out the Vixen - okay, it's been just three times now - I'm impressed by how comfortable it feels to use. The size and weight seem just right to me. Stars meanwhile are absolute pinpoints, and the colors are just sublime. I'm convinced that a fine refractor will spoil every other telescope for the observer. There's just something about the sharpness and color that you can't get with another instrument - even if those other instruments lend themselves to much larger apertures. Anyway, tonight I wanted to observe some globular clusters. I started with M13, the Great Globular Cluster in Hercules. Every nebula, galaxy, and globular cluster aside from the Orion Nebula is a subtle find in DC's light polluted skies. Even the brightest require averted vision to see clearly, and the Hercules globular is no exception. Yet with averted vision, I could make out countless tiny stars: diamond fragments against black velvet. Next, I hunted down M80 and M92: two relatively bright globulars swimming in the most light-polluted part of the sky. They were not immediately spectacular, but then, of course, you think about it: the light coming through the eyepiece left its source during the onset of the Last Glacial Maximum (colloquially called the last "ice age"). There's something indescribably special about scouring the most distant reaches of the Milky Way. And these two globulars I had never observed before. The Ring Nebula (M 57) was last on my list. It was a remarkably easy find, and quite obvious despite its relatively low elevation above the horizon. I needed averted vision to clearly see the ring, and I just wonder what it would look like in a truly dark sky. Still, it's always surreal to see M57: a preview of the eventual fate of our Sun. I went to bed content on the seventh, then woke up on the 8th to realize that seeing and transparency early in the morning of the ninth would both be above average. I can't remember the last time that happened. With Jupiter, Saturn, Mars, and the Moon all slated to be in the night sky, I couldn't miss it. I set my alarm to 3:30 AM - then woke up at 2:30, exhausted but ready to go. I packed up my FC-100DC and walked out the door. This time I nearly blundered into a deer while entering the park. For some reason, that deer just wasn't interested in moving. I was again surrounded by rabbits and this time, a chorus of singing birds. It was beautiful. There were the planets and the Moon, all lined up - and there were high-altitude clouds, defying the weather forecast. For the next two hours, I switched from one world to the next, dodging the clouds as best I could. Here I find it hard to put in words the thrill I got when I turned the Takahashi to Mars. Mars is still many months removed from its biannual opposition - its closest approach to Earth in its long orbit - but the view through the Takahashi was so much better than anything I'd seen before that it truly was like I was seeing the planet for the first time. As you can read in this blog, in previous attempts to observe Mars I always wondered whether I could really make out its surface features. No such confusion this time. There was the south polar cap, bright and clear as day . . . and there were its dark albedo features, not only obvious but intricate in detail, despite the relatively small apparent size of the planet. I was flabbergasted. With focal extender screwed in - and even without - the Takahashi is a stunning planetary telescope. I realized just how stunning when I turned to Jupiter. At around 200x, I have simply never seen so much on the giant planet. You had the feeling that, if only you could get a little closer, you could see an almost Hubble-like level of detail. The seeing didn't quite let me do that, nor did those awful clouds. But still: it was stunning to see all those cloud features I'd previously seen only online or in books. Totally obvious - of course - was the great red spot, and over an hour I followed along as it moved toward the limb of the planet. The four Galilean moons were all lined up, and I could easily make them out as disks. Saturn was equally spectacular, of course. At around 250x, the view was a little dim with those clouds rolling in, but impressively detailed. It was not quite the best view of Saturn that I've had with the Takahashi - owing, I think, to those clouds - but it was close. Cloud features were plainly evident, as was the shadow of the planet on the rings - always a highlight for me. The Cassini Division clearly surrounded the entire planet. Not to be outdone, the Moon was just as impressive as the bigger, more distant worlds. The pictures didn't quite turn out as I'd hoped, but wow: the detail was perhaps even more spectacular than it was on May 31st, and this time without any false color at all. I observed at around 250x for a while, savoring the view especially with TeleVue Plössl eyepieces attached to a 2.5x PowerMate. Crater peaks and rilles in particular were breathtaking to resolve and follow.
I had one quick look at the Ring Nebula before the Sun came up. Although its constellation - Lyra - was now much higher in the sky than it had been on the 7th, the brilliant Moon made up for it by washing out fainter objects. The nebula was quite easy to make out, but dimmer - slightly - than it had been through the Vixen. Now the Sun was coming out, and I had to rush home for my young son's wakeup time. Having had just two hours of sleep, it would be a long day. But so worth it after such a memorable night. |
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