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.
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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! 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! |
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