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.
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It's been a remarkably cloudy month. I even travelled briefly to Arizona, and even there, in the desert: rain. I could scarcely believe it. But at last, tonight the clouds parted over Washington, DC, and although the sky was just a bit hazy and I didn't have much time, I figured I'd take the TV 85 to the rooftop anyway. I'm so happy I did. When I stepped out, the Moon was high in the sky - just passing the Pleiades, actually - Venus was still well above the horizon, and Orion was glorious overhead. I just picked up an AYO II mount - a much sturdier upgrade over my VAMO Traveller that took about four months to manufacture and ship - and was eager to see how it would perform. It's odd: seeing for me can vary enormously from one part of the sky to the other. Part of the reason no doubt has to do with how often I observe from a rooftop. Warm air rising from my building naturally obscures anything too near the horizon. But after observing from enough parks, I'm convinced that DC must have some unusually turbulent - or at least complex - skies. In any case, Venus was a bit of a mess for me tonight, though of course I could clearly make out its phase. And I was impressed to see very little false color around its disk - none when the seeing briefly stabilized. The Moon, by contrast, was just stunning. I know I've sung its praises repeatedly in these pages, but wow: the TV 85 is a miraculous telescope. Maybe I just have a perfect sample? Once again, I saw absolutely no false color on the Moon. Once again, the view was absolutely razor-sharp, with that beautiful cold, white hardness that the Moon can have when it's high in the sky. And the mount clearly made a difference in stabilizing the telescope. It's a hair less smooth than the Traveller, but much sturdier and nearly as compact. This time, I enjoyed picking out the subtlest shadows I could spot at nearly 200x. It's always striking to me that those shadows can give the impression of towering peaks on the Moon - the impression of the lunar landscape that prevailed until the Space Age - whereas of course the Moon's surface is quite flat compared to Earth's. It's amazing, the optical illusions oblique light and a lot of distance can inspire.
TeleVue, it seems, does not get a lot of love compared to its competitors: Takahashi, for example, or AstroPhysics. Apparently TeleVues show just a bit too much false color, and their cost is just a bit too high. But when it comes to optical quality, my TV 85 is easily a match for my FC-100DC. False color is absent; stars are absolutely pinpoint. The TeleVue also seems to focus just ever so slightly more perfectly than the Takahashi - although that may be a result of its smooth, two-speed focuser - and it cools down more quickly. The Takahashi, of course, is all but flawless in its own right. And it draws in more light, which does make it better for some purposes. All the same, I've never been disappointed after observing with the TeleVue; I've never felt that I really should have brought out a bigger telescope. It's an incredible little instrument. 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. It's been cold here, for DC standards, and often windy, and the nights have had an annoying tendency to cloud over at short notice. In those conditions, the TV 85 really is ideal. It cools more quickly than some of my eyepieces, it sets up in a matter of minutes, and it consistently provides views that exceed my expectations. It really is a magical little telescope. I have never been anything other than impressed after using it. The other night, I walked onto the observation deck just as clouds were rolling in from the west - weather forecast be dammed! They moved far more quickly than I thought possible; after I set up my telescope, they had almost reached the Moon and Orion. I had just seconds to take pictures before they arrived. I did catch a short video of the first streamers beginning to race by the Moon. Just a few minutes later, however, I had to pack up. When the windchill is cool enough to numb your fingers, it's always a mixed feeling when you have to walk in earlier than you expected. Last night, the sky was perfectly clear, but the seeing was mediocre at best and transparency wasn't great either. Still, the Moon was high in the sky, and not quite full, with intricate vistas I haven't often observed coming into view along the retreating terminator. This time, I was driven inside not by wind-blown clouds but by the windchill. Luckily, I've become quite good at realizing when my fingers are in trouble.
Still, with temperatures at around -1° C before the windchill, the TV 85 gave me some spectacular views in no time. And although some complain that TeleVue telescopes reveal just a bit more false color than, say, Takahashi telescopes, I see no difference between the TV 85 and my FC-100DC. At the limb of the Moon, with the telescope acclimated, there is absolutely no false color. The divide between the brilliant lunar surface and the inky blackness of space is absolute. Not the best observing nights, but the combination of the Moon and the TV85 never fails to please. 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.
Every Christmas, I head to Winnipeg with my family to visit my in-laws. It is painfully, mind-numbingly cold, and of course I miss my telescopes back home. Yet I've managed to cobble together some equipment that lets me scratch my astronomy even while far from home. This Christmas, I bought an Explore Scientific Twilight I mount to store in Winnipeg. This is my second time purchasing that mount - I sold my first purchase to help finance my VAMO traveller mount - and I again find myself both impressed and disappointed. The mechanics are, on the whole, quite good. It looks great! But quality control at Explore Scientific seems spotty at best. Twilight mounts have magnets that hold an allen key you use to adjust the inclination of the mount head. Both mounts I purchased had hanging magnets, only partly attached with glue. This new mount is smoother than the old one, but again the slow motion knobs just don't stay tight for long, which means that there's give in the slow motion controls. Not a big deal, but I've found that this is the biggest difference between premium products and that next step down: you know just what you're getting when you pay top dollar. In any case, the mount makes a good pairing with the C90 I already had in Winnipeg, but not a great one. The C90 is almost comically over-mounted. I also managed to buy a C6 for Winnipeg this time around - they're bizarrely cheap right now - but it hasn't arrived yet. I felt its absence keenly when I tried to use the C90 to observe the crescent Moon on a cold (-20° C, or -4° F) morning soon after arriving in Winnipeg. Maksutov telescopes take a notoriously long time to reach thermal equilibrium - it's why I don't have one in DC, where I have to observe soon after setting up - and the C90 is certainly no exception. After 30 minutes the C90 hadn't come close to reaching thermal equilibrium, and the view was a blurry disappointment. The C6 should cool down a little faster, and then provide better views. Roughly a week later, on a clear and positively balmy (around -8° C, or around 17° F) Winnipeg night, I stepped out after letting my C90 cool for around 45 minutes. ClearDarkSky told me that seeing would be mediocre at best, but in fact I found it remarkably good. The stars scarcely twinkled, and in fact for many minutes I enjoyed just looking up at the night sky with naked eye. When I turned to my telescope, I found the standard C90 finder to be every bit as bad as I remembered. It's literally unusable, and unfortunately the long focal length of the C90 makes it hard to use the telescope at low magnifications as its own finder. In the cold, I eventually found the Orion Nebula, and the view surprised me: not quite as good as what I see through my TV85, but not too far off. Through Winnipeg's dimmer light pollution, the nebula seemed about as bright as it does with the refractor back home. After a little while I managed to see Rigel, too, and there was Rigel B, plain as day. With bright stars the difference between refractor and Maksutov telescopes is a little more obvious: though the C90 does a good job, stars are just a bit more colorful and a good deal sharper through the TeleVue or Takahashi. I gave up trying to observe Betelgeuse by telescope but did linger on it with naked eye. The giant star has been dimming of late - in fact I noticed that a couple weeks ago - and some think it may soon explode in a supernova brighter, from Earth, than the full Moon. In any case before long my fingers started to go numb, so I picked up my whole setup and simply carried it inside, in one go. All in all, a good night. The C6 will likely reveal far more, and I look forward to using it here in Winnipeg. A glorious full Moon tonight, in bitterly cold weather. While it was -1° C outside with a windchill of -4, it certainly felt a lot chillier on our observation deck. The TV 85 cooled down mercifully fast - even faster than my fingers - and I was able to observe some interesting details on an almost blindingly bright Moon before I started to worry about frostbite. Over the past year, I steadily replaced my Celestron and Explore Scientific eyepieces with TeleVue equivalents, and some nights I really notice the difference. This was one of them. The eyepieces are just so crisp and clear; so easy on the eye. Of all the astronomy equipment I've purchased, my favorite might just be the TeleVue 3-6mm zoom eyepiece. It really gives up nothing but field of view to much more expensive, fixed-magnification eyepieces, with the possible exception of my Ethos. To me, there's always something a little miraculous about seeing the full Moon through a telescope, especially after you've become acquainted with its partly illuminated surface. Owing to shattered glass forged in the fires of cosmic bombardment, many features on the Moon reflect light directly back to its source, rather than off to the side. Much that is usually invisible on the lunar surface therefore pops into view when the Moon is full, including the glorious ray systems around some of the Moon's biggest craters. It's partly why it took "Selenographers" more than two centuries after the invention of the telescope to draft a passably accurate map of the Moon.
Luckily - or perhaps not - we now have cameras. My iPhone never quite captures what I see, but it's always nice to share something after a night outside. 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! 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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