Once again, the sky was clear and the seeing better than terrible last night, so out I stepped onto my rooftop. With a curfew on from 7 PM - what a strange and distressing time this is - I couldn't go outside. Luckily, there were very few people on the rooftop, and no helicopters hovering low in the sky. The Moon was three-quarters full, and with no planets in the sky and transparency quite low, it would be my focus once again. I really wanted to see if I could make out more chromatic aberration tonight through the FC-100DC; the view a couple nights back had made me reconsider the focal extender I'd bought for the telescope. A band of ragged clouds obscured the Moon as I stepped outside, but they passed within a few minutes. When the Moon emerged, I noticed no - and I mean no - chromatic aberration at all, not even on the lunar limb. The seeing was, by then, pretty unsteady, but I did manage to get some spectacular views of the crater Gassendi at around 200x. Nineteenth-century Selenographers imagined that the crater's central mountains changed in shape, betraying - they thought - signs of volcanism or perhaps even life on the lunar surface. It's been a joy for me to learn a great deal about the Moon's cultural and scientific history as I work on my next book. It gives added depth to these nights of lunar exploration.
Last year, Takahashi debuted a seeming upgrade over the 100DC: the 100DZ, a telescope with better color correction and even fewer lens aberrations. Observers report that, visually, there is not much difference between the DC and DZ - certainly not on most nights - but still, in this hobby you always want what is just out of reach. A telescope that promises to show you ever so slightly more, even once in a blue Moon, can be extremely tempting. However, last night clinched it: I'll keep the DC for now. The DZ is about a third heavier, and there is just something about having such a lightweight, easy-to-mount refractor that still shows so much. And now, with the extender, it's almost as though I have two telescopes in one, both just about perfect for different roles, and one that, apparently, shows absolutely no false color in my usual observing locations.
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Last night, miraculously, the clouds cleared rather than thickened after sunset, and seeing conditions lingered - for just an hour or two - near average. I dutifully set out with my Takahashi, yet when I reached the rooftop I found it crowded with people. It's like we, as a city and country, have simply decided to ignore COVID-19. Disappointed, I walked downstairs and decided to set up shop on a bench just outside my building. While I was tucked mostly out of sight, there were bright lamps everywhere, and so I had little choice but to observe the Moon. Not ideal, but not the worst: there are few better things to do than explore the half-full Moon with a fine refractor. With the Moon at 60x, it was immediately obvious that it was going to be a special night. Maybe the seeing was supposed to be average overall, but the Moon seemed unusually sharp. Switching to around 200x, I could easily make out a number of craterlets within the crater Plato, and I was delighted to make out the towering shadows of its mountainous rim. Mountains on the Moon are rounded by years of bombardment, but they nevertheless cast spectacular shadows with the Sun at locally low elevation. These particular shadows, in Plato, have an especially interesting history. In the nineteenth century, observers announced that their flickering betrayed the existence of a lunar atmosphere. The apparent appearance and disappearance of those craterlets, meanwhile, supposedly revealed ongoing volcanism. Was the Moon an active world? To many of the era's leading Selenographers - geographers of the Moon - it certainly seemed to be. It was one of those nights where you could just linger endlessly over the minutest details on the lunar surface, exploring the complexities of terrain you've never really seen before. The Moon's mountain ranges, in particular, had a towering, three-dimensional feel to them. The glint of mountains catching the rising Sun in the blackness just beyond the terminator always gets me. I can just imagine what it would be like to stand on one of those peaks, taking it all in with the Earth overhead. Nearly as striking as the specular detail I could make out, however, was the chromatic aberration I could clearly see, despite using a telescope in the FC-100DC that is nearly free of color - and despite using a focal extender that should have all but eliminated false color. Stepping away from the eyepiece, I noticed that the Moon had a hazy look to it, with yellow distortion around the disk. Could the atmosphere be causing all that false color? Or was it stray light entering the optical tube? I'm still trying to figure it out - but it's definitely something I'll monitor. Nevertheless, a memorable night - and not least for the wail of police sirens in the background, amid protests here in DC over yet another expression of racial injustice. At least there was the SpaceX launch, earlier in the day, to give us a measure of hope for the future.
To put it lightly, conditions here have been far from ideal for observing. Our rooftop is now closed, following DC's lockdown order, and even going inside feels increasingly perilous (though some models suggest we may be approaching or even passing our COVID-19 peak). The weather, meanwhile, has been nothing short of atrocious, with almost unrelenting cloudiness at night, even after clear days. Tonight, the sky finally cleared up for a few hours. The astronomy forecast told me to expect better than average transparency with worse than average seeing. Since I usually specialize in lunar, planetary, and double star observing - the stuff I can do from the city almost as well as the countryside - I typically prefer good seeing over good transparency, so again it promised to be a sub-par night. Still, I had to take a telescope out before the mosquitoes come out in late spring. With the rooftop closed, I may not be able to observe comfortably for a long time when they do appear. Sadly, even municipal park is closed, too, so I was forced back to my old observing site, in a community garden with rows of plants and flowers that together create a labyrinth. Sadly, in the past two years two new buildings have popped up nearby, each with floodlights, so the spot is much worse than it once was. And even though I brought my FC-100 DC - my all-around, can't miss workhorse - on my lightest tripod, the ten-minute walk with all my gear was nothing if not uncomfortable. Still, there was Venus, just a few months from its opposition, almost comically bright in the western sky. I recently upgraded the Takahashi with a Rigel Quickfinder, which makes it so much easier to point the telescope. Within moments, Venus was in my sights. I bought a new Baader diagonal too - the best of the lot - and hoped to see a bit more of the planet than I had before. Indeed, the view was probably my best of the year, although with Venus that's not saying too much. It was quite low in the night sky, and it did have noticeable false color. Still, the seeing was actually probably above average (!), and there were moments when the atmosphere settled down enough for some sharp views of the planet and its striking cusps. I don't expect a better view this year, and wow - I even managed to get a (terrible) picture! It was atmospheric transparency that seemed far below average tonight. When I turned to the Orion Nebula, for example, the view was pretty disappointing. Orion is getting low in the night sky, and I've discovered that that makes a huge difference for its famous nebula in particular. As soon as the atmosphere gets too thick, the nebula starts to blend into the rest of the sky. Pointing to Rigel, however, I was astonished at the brightness of Rigel B and the separation I could see between it and Rigel A. It was the clearest view I've had of this spectacular star system. By then, the nearly full Moon was on the rise. It was a "Super Pink Moon," apparently, and although that doesn't refer to its actual color, bizarrely the Moon did have a pinkish hue near the horizon - a product, I suspect, of a hazy atmosphere with high humidity. Taking any pictures proved to be a nightmare. Since I can't sit in the garden, my hands and especially my legs are far less steady than they are on the rooftop. The picture above is the best I got, and doesn't quite capture the clarity of the image.
It does reveal, however, the excellent color correction on the Takahashi. I'd been tempted to replace the DC with a DZ during a recent Takahashi sale, as I mentioned below, but figured that the much lower weight of the DC made it a better bet for me - and that the visual performance would not be noticeable most nights. I felt a bit better about that decision after last night, though still: once you develop expensive eyes, it's hard not to imagine what even better color correction might be like. Towards the end of the night, a few deer nearly blundered into me, and they seemed a bit reluctant to leave when I greeted them. I kept hearing their rustling nearby. Then, I nearly stumbled across a raccoon on the walk home. With fewer people on the streets, DC's other residents seem to be taking over. The sky was clear the past two nights, as if to compensate for the arrival of COVID-19 in our city. Temperatures are rising, too, although they were plenty cool during that first night (March 7th). Since our baby still wakes up all the time - including every 1-2 hours at night - I once again walked up to our roof. Someday, I hope to be able to visit nearby parks again. On both nights, I stepped out with my Takahashi FC-100DC. The telescope is absolutely stable on my next AYO II mount - a significant difference over the AYO Traveller mount, especially in windy weather (and it's been a bit breezy here on the rooftop). Although ClearDarkSky forecast average seeing on both nights, I've learned to take that with a couple grains of salt, and indeed once again there seemed to be pockets of decent and poor seeing in the night sky. On the 7th, the nearly-full Moon appeared reasonably steady through my eyepiece; on the 8th, a high-altitude haze and turbulent air worsened the view considerably. Still, there's always something satisfying about seeing the apparently full Moon in the night sky, and then discovering a terminator with a telescope. I can only step out at around 8:30 most nights - after my daughter goes to bed - and at that point Venus, which is now near opposition, is sinking quickly towards the horizon. Not only does it then shine through a lot of atmosphere, but it's also just above a bank of currents boiling up from some pipes on our rooftop. And when I turn my telescope to have a look, it's usually right after I set up, when the tube still hasn't fully cooled down. Venus is, in other words, usually a shimmering mess of false color. Yet on the eighth, for maybe five glorious minutes, I did get a nice view early in the evening, at around 82x with my Nagler Type 6, 9mm eyepiece (it's a favorite). Any more magnification, and the view softened in a hurry. At 82x, however, I thought I might just be able to make out some darker details in the disk; in fact I was quite sure of it, but of course unlikely visual phenomena that are just at the edge of perception should always be taken with a healthy dose of skepticism. Minutes later, the view broke down and Venus was out for the night. On both nights, with Orion very high in the sky, I easily split Rigel A and B. Turning to the Orion Nebula, I think I was able to make out five - perhaps even six! - stars in the Trapezium on the 7th. At 123x, the whole view seemed full of delicate nebulosity (faint, however, because I'm surrounded by lights on our rooftop and my eyes don't fully dark adapt). On the 7th, a small crowd came out to our rooftop and one young man wandered over. He asked me what I was looking at; I mentioned the Orion Nebula. "What's a nebula?" he asked. Vinny - that was his name - now you know! On both nights, I did a little equipment testing. First, I've been tempted by the new Takahashi FC-100DZ. Its color correction is a bit better than that of my 100DC, especially at red wavelengths. With Mars reaching opposition later this year, it might be an upgrade worth making. On the other hand, the slight improvement in color correction comes at the cost of a longer focal ratio (F8 VS F7.4) and a substantially heavier (33% more!) tube. That may mean that I can't mount the DZ on my lightest-weight tripod and mount. And I wonder whether the DZ would complement my Mewlon as nicely as my DC can - at least in theory, since I rarely have a chance to use the Mewlon. The false color around Venus and even the Moon on the 8th (in poor seeing) did make me think, but for now I definitely lean towards keeping the DC.
I also tested a new pair of binoculars on the eighth. For a while, I've been looking for binoculars that aren't too expensive - I don't use binoculars enough to justify a high price - but also are more than toys. The big Celestron 15x70 binoculars that I've mentioned earlier in this space quickly fell out of collimation and are now completely useless. I bought a small (8x42) pair of well-reviewed Oberwerk binoculars last year, but they were surprisingly heavy, and they too lost collimation in a hurry. I returned them and replaced them with Nikon 10x50 Action Extreme binoculars. Right off the bat, the feel and size of the binoculars felt right. They were actually easier to hold steady than the smaller Oberwerk binoculars. Turning to the Moon, the view impressed: a bit of false color no doubt magnified by that high-altitude haze, but wonderfully sharp nonetheless. I think this pair is a keeper, and at $150 I don't have to feel that it represents a blown investment if I don't use it much. With the Moon and Orion high in the sky just after the kids went to bed, and the weather relatively mild, I just had to have a look. Once again, I hauled my Takahashi refractor to the rooftop - although I'm not sure "haul" is the word to use for carrying such a light telescope, mount, and tripod. The currents coming off my building again add an artificial layer of low-lying turbulence to the view, and I'm starting to suspect that my Berlebach Report tripod can barely handle the FC-100DC (the TV 85 is a slightly better match). There's a bit more vibration than I usually prefer, though I'm sure that's also a function of the wobbly concrete slabs we have on our rooftop. In any case, although the seeing wasn't bad, the Moon trembled in the eyepiece. Still the view was, at times, utterly spectacular, especially around Plato, where the rim shadows seemed fantastically long and sharp: as though they were cast by a gigantic palace overlooking the crater. At times it seemed as though the shadows shimmered ever so slightly, an effect first noticed by Selenographers in the late nineteenth century (and then blamed on "lunar meteorology"). Although the crater floor is pitted with tiny craterlets - well, tiny as viewed from Earth - I couldn't spot any. Is it futile to look for them with a small refractor? Maybe. I'll need to bring out my Mewlon when the weather is warmer. The 3.7 mm Ethos eyepiece certainly makes a big difference on the Moon by greatly expanding the field of view, but the 200x it affords was just a bit too much for the atmosphere tonight. The view was just a little soft. Turning to the Orion Nebula with the eyepiece attached, the Trapezium wasn't as sharp as it was the other night, and the nebulosity surrounding it was a little washed out - partly, no doubt, by the brighter Moon. A lower magnification would have served me better, but I had to hurry downstairs to kids who needed my attention. All in all, a good hour on the rooftop. Someday, I keep reminding myself, I'll be able to stay outside for longer!
Just a short post this time because, wow, has this month ever been busy for me. Either I've been sick or my kids have been sick, and there's far too much to do at work, so there's no chance for me to observe anywhere other than our rooftop observation deck. I can pack up my telescopes quickly when my wife needs my help - or when I'm just too sick to endure the cold for long. Luckily, Orion is riding high in the sky during the fleeting minutes I usually have to observe, and that makes for some impressive viewing even from my light-polluted rooftop. Last night my Takahashi refractor gave me some beautifully ethereal views, with delicate nebulosity filling almost the entire field of view at just over 80x. I recognize that the above picture is, of course, terrible on some level. But with an iPhone, held by shivering hands on a cold night? It's not the worst! The seeing must have abruptly worsened, because I spotted only hints of Rigel B and the white dwarf orbiting Sirius (the "pup") with a Nagler 9mm eyepiece. Both stars danced and flickered. Should I have used a higher power eyepiece? Maybe, but it was just too cold. In any case Betelgeuse was striking, even with the naked eye. It's dimmed to an extraordinary degree over the last few months! It's a sobering reminder that even stars diminish and die (although Betelgeuse may not go supernova for many thousands of years yet). A crescent moon is always a spectacular sight through any telescope, let alone the FC-100DC, and luckily I set up just before it slipped too low in the night sky. Still, I had to observe through a lot of atmosphere, and through currents welling up from the rooftop (my primary antagonist on our observation deck). As the pictures attest: the mesmerizing detail I can often see when the Moon is higher in the sky just wasn't there last night. But as always, the Moon was worth a look.
Not the best night, but any time I can get a quality view of the Orion Nebula from the city, I'll take it. After quite possibly the worst travel experience of my life - thanks, United, for losing two car seats and a suitcase - we returned to Washington on New Year's Eve, where I was happily reunited with my best telescopes. The sky was beautifully clear and transparent on the first day of the new year (and decade), so I decided to ring it in with some Moon watching. Anything above freezing now feels positively tropical to me, so I was quite comfortable on our observation deck. I would have preferred to walk to a nearby park, since it's too bright on the deck for my eyes to fully adjust to the dark, and that keeps me from enjoying deep space objects as I otherwise might. But my infant son still isn't sleeping, and I need to be on call. Luckily my telescopes pack up in under five minutes. I began by observing the waxing Moon with a 25mm eyepiece in my Takahashi refractor, for a magnification of about 30x. Immediately, I was simply floored by the difference between that view - which came after about five minutes of acclimation - and the one I'd had through the C90 in Winnipeg. As usual, iPhone pictures simply can't do it justice. The Moon was rife with such extraordinary detail, even at that low magnification, that I could have stared at it for hours, and it had a three-dimensional quality that it never appears to have through a lesser telescope. Although these pictures don't show it, I could clearly see the Moon's ashen light - Earthshine bouncing off its otherwise unilluminated surface - even by naked eye, and the contrast between the sunlight and Earthlit parts of the Moon was glorious through the Takahashi. Shifting to higher magnifications, I quickly realized that there was something odd about the seeing last night. Looking west, away from the bulk of the city, the view of the Moon was turbulent but stabilized briefly from time to time, revealing glimpses of extraordinary detail. Looking east, towards downtown, the seeing was consistently below average. The Trapezium at the heart of the Orion Nebula, for example, was a disappointing sight. In Winnipeg, the C90 had provided a better view - proof of the obvious fact that, no matter which telescope you use, light pollution and atmospheric conditions will play a huge role in determining what you see. Betelgeuse danced wildly through the eyepiece, but still I was struck by how much it had dimmed over the past few months. Will it explode soon? It's vanishingly unlikely, but still possible . . . and if so, I'm happy I paid my final respects through the eyepiece. I've always loved comparing it to Rigel.
Observing deep space objects from the city is always in equal parts exciting and disappointing. Exciting, occasionally because of the beauty of the object (the Orion Nebula, for example), but especially because of the thrill of overcoming our local light pollution to see something so far away. But disappointing because I always know how much more spectacular just about anything in deep space would look in a truly dark sky. Not so the Moon or planets. I can see them just as well from my observation deck as I could out in the wilderness, and that's a nice feeling. Last night, I stepped out in conditions that were supposedly less than ideal: below-average seeing and poor transparency (the latter actually doesn't matter so much for lunar viewing, but still). When I walked outside with my bags, the clouds were in fact just rolling in - an hour or so ahead of schedule - and the first wispy filaments were beginning to shroud the Moon. Undeterred, I set up my Takahashi FC-100DC. To put it lightly, I did not regret my decision. The seeing, as I judged it, was in fact above average, and occasional moments of tranquility and clarity made for some of the best lunar views I've ever had. I used a huge new eyepiece - an 3.7mm TeleVue Ethos - for spectacularly detailed exploration at exactly 200x (the theoretical maximum magnification of a 4-inch telescope, although fine optics can be pushed beyond that limit). It really does feel like exploration at that magnification, with my optics, and with the seeing so calm. Recently, I've been writing about the spurious sighting of a lunar city by one Franz von Gruithuisen in the 1820s. Last night, I could see how he went wrong. The Moon is revealed as a truly complex and vibrant world through a good telescope and a steady atmosphere. With the Moon just past its first quarter, a lot of spectacular and historically significant features are clearly visible. Indeed the Moon used to be one of the least interesting objects in the sky for me; good for a quick (admittedly spectacular) view, but not much else. Now, after reading and writing about the Moon's natural and cultural histories, I find it endlessly fascinating. I could spend countless hours exploring its environments, which now seem diverse and dynamic to me. It didn't take long before those clouds arrived in earnest. Even then, it was striking to see them rush past the Moon at relatively high magnification. At low magnification - just 23x! - the Moon was still absolutely crystal-clear, despite those clouds, and in fact more beautiful than I've ever seen it. The combination of the Takahashi refractor and the Ethos eyepiece worked spectacularly well in average to above-average seeing. Of course, my phone just couldn't do justice to the view, but I do think my images have improved a great deal, and even the video above - which shows those clouds setting in - is better than I could have managed a few months ago. Progress! Last week, it was clear for two nights in a row, with the Moon below the western horizon and all the bright planets setting soon after the Sun. A good time, I figured, to have a look at Orion - rising to the east at around 8 PM - and track down some double stars that I'd missed in years past. I've recently become much more interested in double stars, partly because I now imagine what the sky must look like from orbiting planets. On both nights, I was forced to use our observation deck. My daughter was a little sick, and I had to be on call in case she woke up and needed something. Since it's illuminated, the deck is a terrible place for deep space observation, but it's a whole lot better than nothing. Unfortunately, atmospheric turbulence was high and seeing on both nights was therefore somewhere between atrocious and worse than average. Not terrible for low-power observation of Orion and open clusters, but nowhere near good enough for splitting tricky double stars. On night one, I stepped out with my Takahashi refractor: my go-to, all-around telescope, especially in cold weather. The seeing was then closer to atrocious, especially near the horizon, and views of Orion were not exactly the best I've had. I've focused on getting great equipment, but more often than not it's the atmosphere that limits what I see at night. On top of that, it was gusty on the observation deck: gusty enough to actually push my telescope. Not a great night, to put it lightly.
Undaunted, I stepped outside on night two with both my TV 85 and my Mewlon. I observed for around 45 minutes with the TeleVue, lingering on the Pleiades and Hyades: brilliant open clusters that are now high in the sky and therefore spectacular at around 9 PM. The seeing was well below average: bad enough to notice at low magnifications, but not bad enough to spoil the view (in contrast to the previous night). After a while, I mounted my Mewlon. For over a month, I've waited for a sturdier mount to arrive from Stellarvue, but no success. I've had to cancel and go with another option, from the manufacturer of the only mount I have now: my VAMO Traveller. This mount is downright miraculous for its light weight and ability to handle substantial telescopes, but it's overmatched with the Mewlon. The view was therefore a little wobbly, and the problem was compounded but two equally bad problems: the seeing near the horizon, especially with the higher magnifications that the Mewlon permits, and the thermal state of the telescope, which had still not cooled down in the low temperatures (it was around 7° C). Stars danced in the eyepiece, or even stretched into short lines: a bizarre effect that I've rarely seen. Still, by around 10 PM, at modest magnification, I did get a decent view of Orion: a great deal brighter and perhaps more impressive than what I'd seen with the TV 85. Rigel A and B were also much easier to split with the Mewlon than with the TV 85, though I did manage it through both telescopes in spite of the awful seeing. Castor A and B also made for a brilliant and impressive binary, though, again: it was hard to find the targets I was hunting for with the opaque sky (transparency was low) soaking up DC's light pollution. In short: not the best night for the Mewlon, and exactly the kind of conditions in which the TV 85 can match much bigger telescopes. As usual: I'm still happy I stepped outside! A short observing session tonight on the observation deck with the FC100-DC, in temperatures cold enough to become uncomfortable after a half hour or so. Despite the hazy conditions and nearly full moon, I tried to get a shot of the Pleiades, then high in the sky. For once taking a picture with my iPhone worked better than taking a video (the above shot of the Moon is a frame from a video). I'm not unhappy with the result, considering it's the product of a phone (and a very good telescope, granted). The Takahashi refractor showed some absolutely stunning details tonight on the fully illuminated parts of the Moon, especially around the around the Mare Tranquilitatis and Serenitatis with a Baader Hyperion zoom. There was the sense that you could keep on zooming in forever, with more and more detail popping into view. Even at around 200x, the view remained wonderfully bright; at times almost painfully so. I closed the short evening by hunting for Uranus. Alas: no luck tonight.
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