July 19, 2020
In many cultures, in many times and places, bright comets were thought to herald - or perhaps cause, or confirm - disaster. It therefore seems almost absurdly fitting that, in this terrible summer of 2020, a naked-eye comet has appeared in our sky. I wrote earlier about failing to spot that comet - "NEOWISE" - in the morning, but it's rounded the Sun and is now visible in the evening - a much more convenient time for me to observe. This week I decided to make a concerted push to see it.
I started with a pair of Nikon "Action Extreme" (ugh) 10x50 binoculars, on the 15th. After walking to our rooftop, I scanned the area south of the Big Dipper after sunset. The sky took longer to darken than I'd anticipated, but eventually, around 9:30 PM, I found NEOWISE. It's strange: this was my first comet sighting since Hale-Bopp way back in 1997, and it gave me a complex medley of emotions. On the one hand, it seemed a little underwhelming; Hale-Bopp and Hyakutake in 1996 had given me a wildly unrealistic frame of reference. I vividly remember seeing Hyakutake cover much of the sky, or Hale-Bopp's ion tail still visible at sunrise. By comparison, NEOWISE was a smudge - partly because it's dimmed since I should have been looking for it, a week ago. And on the other hand, what a thrill, nonetheless, to see a relatively bright comet; how exciting to receive such a vivid reminder that our Solar System is a restless and active place.
On the 16th, I marched out again, this time with my Vixen ED115S. Several weeks ago, I tried to sell that refractor to afford my APM 140. I had a sale lined up, I thought, but the buyer kept asking for more discounts. Finally he asked for one more discount and posed a question that forced me to measure the telescope. When I did, I was struck by the beauty of the thing and declined to go lower - then sold some eyepieces instead.
Thank goodness! The Vixen is just about a perfect telescope - it might actually be my favorite. As I've mentioned before, it's just the perfect size and weight for me, and perfectly well-balanced with its upgraded focuser. It provides just a bit more punch than the Takahashi can manage, and although it's heavier it's still very manageable. It's also, somehow, easier to use; the finder is in exactly the right place, the focuser is buttery smooth, and the handle makes it a snap to mount.
Anyway, conditions could not have been worse on the 16th. Not only was it gusty, but the air was murky, thick with humidity, and thin clouds already covered much of the sky - with thicker clouds following in their wake. I scoured the horizon for that comet. Eventually I found it, peeking through high-altitude cirrus, further north than I'd remembered. Since it was already partly obscured, it looked only a bit brighter than it had using binoculars - but there it was, nonetheless, a bright little nucleus with a fan-shaped tail. Jupiter was rising, so I had a look before heading back downstairs. The seeing was terrible and haze covered the planet with a yellow veil, but still - the detail wasn't bad, considering.
Then, miraculously, on the 18th conditions promised to be superb by DC standards: above-average seeing, according to ClearDarkSky, and above-average transparency, with not a cloud to be seen. I rumbled out of my building at 9:30 PM, with the APM in its giant suitcase. It soon dawned on me that I was more tired than I normally am; this was going to be a long, hard walk. After 15 minutes I was drenched with sweat and sore in a million places, but I'd made it to the park and covered myself with bug spray.
I walked around and scouted out what I could see. Finally, I found a gap between houses that afforded me a good view of the comet, plainly visible with the naked eye but very close to the horizon. I had to set up in a far corner of the park to look through that gap, and the mosquitoes were worse there than they are in my normal spot. Still, I got a good view at last.
I was struck by the brightness of the comet's nucleus relative to its tail - and struck, too, how little that tail seems to brighten with increases in aperture. The APM gave a clearly brighter view than the Vixen, let alone the binoculars, but the difference wasn't that great - not as great is it is when I view, say, the Ring Nebula. Still, the view was very satisfying - best with a 17.3mm Delos eyepiece at 57x, I decided. Higher magnifications did not seem to bring out any more detail in the nucleus, possibly because the comet had already neared the horizon. Using averted vision, I thought I could spot a hint of a halo surrounding the nucleus - more than the tail, that is - but that might have been my imagination. Either way, with the APM, a very fine comet; proportionally more elongated than Hale-Bopp, much shorter, of course, than Hyakutake, and far fainter but still aesthetically pleasing.
When the comet got too low in the sky and the mosquitoes got too bad, I migrated back to my usual observing spot, where Jupiter and Saturn were rising to the east. When I had a look, however, I was shocked. The seeing was actually abysmal - some of my worst of the year. It was as though a southerly, high-altitude wind was rushing across my view, distorting and periodically compressing both planets. Jupiter still showed a good deal of detail in fleeting moments of greater stability, and the four Galilean moons all lined up made for a pretty sight.
But I was reminded again that you just can't count on ClearDarkSkies - or any tool based on our weather forecasts - to help you predict what the sky will be like. I enjoyed some of my best views this year - on May 31st, June 9th, and July 10th - when ClearDarkSkies predicted poor to average seeing, and some of my worst views when it predicted good seeing. In particular, seeing seems to differ in different areas of the sky, and you never know what those areas will be.
On a mechanical front, I swapped my red dot finder for a right-angle finderscope on the APM, and that made a huge difference for the better. It's much easier to find things now with the big refractor. On the other hand, I also had a big more trouble using the telescope on my AYO II mount. I had to tighten the mount considerably to keep the telescope stable, which meant that it was harder to nudge along as I tried to keep up with the movement of the comet or planets. I might have been a little too impatient; maybe I should have worked harder to balance the telescope perfectly - but that balance does shift as I change eyepieces. At some point, I'll likely have to bite the bullet and buy a slightly sturdier (and heavier) mount. At least there's minimal wobbling after I do give a nudge.
On another front, I suddenly realized last night that, after selling eyepieces to fund the APM, I suddenly have a dearth of high-magnitude eyepieces with a good field of view. When I can afford it, I'll need to invest in some more eyepieces. Or maybe I should sell more things I don't use? It never ends.
To conclude, NEOWISE ultimately offered some memorable (if all too brief) views, and the refractors, as usual, acquitted themselves nicely.
June 9, 2020
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.
May 26, 2020
It's been a while! With around 8,000 COVID-19 cases confirmed in DC - and who knows how many undiagnosed - I've resolved to use my telescopes only in conditions of average or better seeing, and only with at least one showcase object in the sky. For two months, that combination basically did not materialize. Conditions were so bad for astronomy here in DC that I saw plenty of advertisements for telescopes published by people in and around the city.
A couple weeks ago, the sky was finally clear. Although seeing was below average, I couldn't stand being cooped up in my apartment any longer. I took my TV 85 to our rooftop and had a look at the rising full moon. Though the TeleVue never disappoints, the atmosphere was just roiling, and the view was soft. I could only use low magnification. Still, it was nice to catch a glimpse of something astronomical.
Then, last night, seeing was briefly better than average - it's been so long since that happened - and at dusk the Moon was a beautiful crescent hanging over the western horizon. This time, I took out my Vixen ED115S, and resolved to walk around ten minutes to a nearby park. After two minutes of walking with all my gear, I was sore, sweating, and ready to quit. I ducked into a nearby driveway, then walked over to a patch of grass bordering a private school and forest. From there, I could see the Moon in a gap between trees. Good enough!
With the Moon sinking towards the horizon, seeing was not quite as good as I expected. Or more accurately: it was inconsistent. At times, the view was a little fuzzy, or perhaps hazy; at other times - and briefly - it was crystal clear. Still, I now had my first opportunity to test the Vixen in conditions that were better than terrible.
It's an impressive telescope, no doubt about it. It's immediately obvious that it gathers more light than the FC-100DC. This was not a given, because small Takahashi refractors are renowned for outperforming larger telescopes. But subtle features, such as rilles, that are hard to see in my smaller telescopes are clearly visible in the Vixen, giving a mesmerizing complexity to the lunar landscape. You truly get the sense that you could explore it forever. And in particular, the "ashen glow" of the crescent Moon - that majority of the lunar disk illuminated by Earthshine - was much brighter than I can ever remember seeing it. I could actually make out a lot of features on that part of the Moon - a first for me.
Above all, the optics are sharp. I also feel that they take noticeably longer to cool down than those of the TV 85, for example, or even the Takahashi. And if you really look for it, you can see just a bit of false color on the lunar limb when the Moon isn't perfectly in focus. It's just a hint of greenish-yellow, but it's there. I guess I've developed expensive eyes while using these fine refractors. I actually doubt that I'd be able to see even these hints of false color with the Moon higher in the sky; that's something to check out next time. Still, for now I think there may just be a bit more of that color than I can make out with the Takahashi.
There's also more coma - more distortion on the edge of the view - than I see through my smaller telescopes. This is not surprising, and it does not feel distracting to me; you really have to look for it to notice it. But notice it I did when the sky darkened and a star appeared near the Moon at low magnification. My Vixen has a number of heavy upgrades, and that makes it about twice as heavy as the FC-100DC. Still, the AYO II mount holds it with no problems at all. The view, in fact, is rock steady - better than I expected. I can't give that mount enough praise.
After about 40 minutes, the mosquitoes were out in force and I had to pack up quickly. A pity; I'd hoped to catch a glimpse of some other objects, but I have to admit that my observing site was far from ideal anyway.
I am very happy with this telescope. The optics are superb, if not entirely color-free, and it just feels good to use and handle. It's almost the perfect size for a medium-sized refractor; any bigger, and you get the sense that it would be much harder to mount. As is, you barely notice it's there sometimes. You could get lost in that view.
The Vixen provided another useful lesson to me last night. With a heavy heart, I decided to sell my Mewlon 180. Although the telescope is absolutely beautiful, it just takes too long to cool down - and it's too heavy to carry far in its case. I've been debating whether to use the funds to buy a larger refractor, but now I wonder whether the Vixen is the biggest telescope I can manage - until I have a backyard or car, at least.
March 30, 2020
Life - for me, for millions in the United States and around the world - has changed just a bit since I last wrote. Friends and students have fallen ill, and so many have lost their jobs. It feels crass to complain, but still: my family of four is now largely isolated in our little apartment, and my office is in a walk-in closet. It's less than ideal.
In these difficult and chaotic times, I of course have no way of traveling for work, which means that I have a surplus sitting in my research budget. Not surprisingly, that got me thinking about improving my little telescope collection.
With the Mewlon around, I decided that the C8 was expendable, after all - especially since the device I purchased to make it acclimate more rapidly (a Lymax Cat Cooler), is much bigger and heavier when accompanied with a battery than I'd anticipated. So I sold the C8 and its accessories, then used the profit to buy two new Baader diagonals: supposedly, the best on the market.
Now I had three telescopes in DC, and really four is probably the sweet spot for me. This past winter convinced me that I'm going to have my easiest observing sessions when it's cold - certainly on the rooftop, since nobody goes up there when it's even a little cool. I decided that I needed a somewhat bigger doublet refractor that would cool down very quickly, but gather a bit more light than the Takahashi FC-100DC could reveal. It couldn't be too big, however, or I wouldn't be able to easily carry or mount it. And it couldn't be prohibitively expensive (not an easy restriction, considering how refractors scale in size and cost).
After doing a lot of research - too much, considering my other obligations - I settled on a Vixen ED 115S. This is a fine doublet telescope that shows very little false color when in focus (so little that it passes as an apochromat), gathers substantially more light than a 100mm telescope, is versatile at F 7.7, and remarkably light at just over 10 pounds. For some reason, it seems to be quite rare.
The telescope is decidedly not cheap, however, though it does ship with second-rate accessories that nevertheless can only be purchased as accessories when buying from TeleVue or Takahashi. To my astonishment, I found the Vixen with a heap of top-rate add-on accessories - tube rings, greatly upgraded focuser, handle, etc. - for sale at an incredible price on Astromart, in used but like-new condition. I pulled the trigger, and the telescope arrived just a week or so later.
For more than two weeks after the telescope arrived, the clouds and rain would not relent. I suppose that's good; coronaviruses apparently do not spread as easily in humid weather. And certainly fewer people went outside. Still it was frustrating, especially as I increasingly worried about navigating my building and touching the germs on every surface. Hauling telescopes through the building increasingly seemed like a perilous prospect.
Then, last night, the sky cleared for just a few hours. I forgot about the pandemic for a moment and hurried to bring both the Vixen and my trust TV 85 to the rooftop. I mounted them on the AYO II: perhaps the finest piece of non-optical equipment that I've purchased in this hobby.
It was quickly apparent that both seeing and transparency were nothing short of atrocious. And I mean atrocious: the night probably offered a worse combination of both than anything I've experienced in the past year. On top of that, gusts of wind rolled over the rooftop, and clouds defied the forecast to move in quickly from the west.
In that context, my decision to bring the TV 85 quickly paid off. I might otherwise have been worried that the new telescope was partly to blame for the somewhat soft appearance of the Moon, for example. But the blurriness and inconstancy of the view were, if anything, even worse through the magnificent optics of the smaller telescope, despite its smaller aperture.
And despite the uncooperative atmosphere, the Vixen impressed. It took just a bit more time to cool than the TV 85, and provided useful views almost immediately. A look at Venus quickly revealed that the Vixen shows noticeably less false color than the TV 85, even in poor seeing. The TV 85 showed a fringe of blue around lunar limb in these terrible conditions; not so the Vixen. It should be noted that, to my eyes, the TV 85 normally offers almost no false color: perhaps even less than the FC-100DC (it's just amazing in that regard).
With its remarkably wide view of view, the TV 85 did provide superior views of the Pleiades. The Vixen dazzled too, but there was just something about the TV 85 view that stood out. Maybe the fault lay in the eyepieces: while I used a TeleVue Plossl in the TV 85, I used a Baader Hyperion Zoom in the Vixen. In my experience, there's no substitute for TeleVue eyepieces.
A look at Orion, however, exposed the advantage of larger aperture. Despite the abysmal seeing, the Trapezium was absolutely crystal clear, with an impressive amount of space between its components. Switching to a 2", 55 mm TeleVue eyepiece revealed all of Orion's belt at around 16x, glittering and glorious despite hazy atmosphere and light pollution.
In short, the new telescope is wonderful: optically on par with the Takahashi and TeleVue, nearly as portable as the Takahashi (though it requires a heavier mount and tripod), almost as quick to cool down, and aesthetically really nice to boot. It is also just a joy to use. There's no fussing with anything, and it works beautifully on the AYO II mount. My only complaint comes by way of comparison: while the upgraded Moonlite focuser is rugged and fluid, the stock TeleVue focuser is just a bit smoother.
Who knows what the world looks like when I next write. In the meantime, it's nice to be reminded - with the aid of two fine telescopes - that the universe will remain more or less the same.