Summer has truly begun in DC when the forecast calls for back-to-back nights with good seeing, and the planets begin to rise high above the horizon. After a very satisfying morning with my Takahashi FC-100DZ, gazing at the southern icecap of Mars, I hauled out my TEC 140 last night and found the same gap in the trees. Once again, there were Mars and Jupiter in the pellucid morning sky, in good (if not exactly great) seeing.
I'd swapped my DM-4 mount for a DM-6, and my carbon fiber tripod for a Berlebach Uni. The heavier ensemble is much more pleasant to use. As I've written in these pages, there's just not beating the mechanical quality of TEC. Every aspect of the 140 is a joy to see and a pleasure to manipulate. The DM-6 and Uni hold the telescope exceptionally well, with virtually no vibrations even when I adjust the buttery-smooth Feathertouch focuser. If I could have just one setup: yes, it would be this.
I've often found an easily noticeable difference at the eyepiece between quality 4- and 5.5-inch refractors. The TEC in particular has given me my finest-ever views of Jupiter and the Moon, with an ethereal, three-dimensional quality and the sensation of texture that I've never had with another telescope.
This morning, however, I was mildly surprised to find that the view resembled what I'd seen the previous morning, using the FC-100DZ. Granted, I could see a star near Mars that I hadn't sighted with the smaller refractor, and the cloud belts of Jupiter definitely showed more detail in moments of steady seeing. At well over 200x, a dark albedo feature on Mars seemed to more clearly extend north from the southern icecap, which of course I could make out clearly.
Yet the difference was, overall, insubstantial. I think amateur astronomers too often exaggerate the importance of equipment in what they can discern at the eyepiece, and too often understate the influence of the atmosphere. In my experience, even subtle atmospheric differences from night to night - and from one part of the sky to the other - can matter more than very substantial differences in equipment (that might make one setup cost many thousands of dollars more than another). It's humbling to know that a $150 telescope - such as the C90 - could outperform an $8000 refractor (such as the TEC 140) on any given night.
I also wonder to what extent nearby streetlights were running interference, softening the view at the eyepiece. Something like that seems to have happened to me before, when my FC-100DC suddenly showed garish chromatic aberration as I observed the Moon under some bright lights.
In any case, several dark markings - barges? - were fleetingly visible in what I took to be the north equatorial and north temperate cloud belts of Jupiter. I was again struck by the pale and almost washed-out view of the planet, where contrast has often seemed so stark with a 5.5-inch refractor. I thought I could make out a very faded Great Red Spot: not much more than a subtle blotch in the planet's southern hemisphere.
After I packed up, I reflected on a recent trip to some astronomical archives, which I consulted to complete my next book, Ripples in the Cosmic Ocean. Among other stops, my travels took me to the archive of the Royal Astronomical Society of Canada, which is tucked away in a little office on the second-story of a nondescript building in Toronto. There's a heap of telescopes in the middle of the archive, and the Society's wonderful archivist explained to me that all of them, in various ways, tell the history of astronomy in Canada. He hopes to mount them in a museum - and indeed I drooled over some fascinating pieces.
One I found particularly striking: a beautifully-preserved little telescope - is it 40, maybe 50mm across? - used by satellite-trackers in Operation Moonwatch, amid the paranoia that accompanied the early Space Age. The mechanical quality really impressed me - the tabletop tripod alone was a diminutive masterpiece - and I wondered what the optics could reveal. I'll bet today's amateurs would pay through the nose for a travel scope like this one.
I visited the archive to look over some astronomical logbooks, and as usual those were a treat. It can be viscerally moving to read over another amateur's drawings and reflections from decades or centuries ago. Our world has changed - and sometimes other worlds have, too - but there's a common thread: the long-dead observer and I both gazed with wonder at something that's far bigger than our fleeting lives. We struggle to put in words what it means for us, as we obsess over equipment and traces of detail in planetary disks.
We are the Universe, conscious of itself - but only briefly.
The planets are rising high above the early morning horizon, and for once the forecast called for good seeing. I slept fitfully until 4:15 AM, nearly convinced myself to fall back asleep, and finally slipped out the back door at 4:45. I soon found that I couldn't see a planet from my backyard, but I did find a spot nearby where a gap in the trees revealed two brilliant planets. They were remarkably close together - not much more than Jupiter and Venus were about a month ago. With the Sun beginning to brighten the morning sky, I set up my Takahashi and targeted the brightest of those planets.
At first, I thought it must be Venus - that's how bright it was - and I assumed the less brilliant, yellowish planet was Jupiter. For a minute or two I thought my finderscope must be misaligned. I kept targeting the brightest planet, and time and again Jupiter showed up in the eyepiece. Finally, it dawned on me - a little later than it might have, had I had more sleep - that in fact the brilliant planet was Jupiter. I was astonished to find that the dimmer - but still very bright - planet was Mars. It's so much brighter now than it was just a month ago - and that, of course, means that it's fast approaching Earth.
I was a little disappointed upon observing Jupiter. Towards the eastern horizon, the seeing was a little worse than I'd expected, and although I could make out many salmon-colored belts, shimmering in the tremulous atmosphere, the planet seemed a little washed out. It lacked the vivid reds and ochres that sometimes create such striking contrast on Jupiter. At just over 200x the Galilean moons were tiny disks, but without obvious differences in color.
Mars, by contrast, was a deeper red than I've normally seen it. For the first time in two years, I made out a polar icecap - this one the southern icecap - and a dark ring around it that was, in the late nineteenth century, widely assumed to be meltwater lake draining off the cap. I could also discern dark streaks shooting up towards the Martian equator. In the nineteenth century, many astronomers - not just Percival Lowell - figured that these were canals and oases channelling polar meltwater towards cultivated fields. That was how the Martians were thought to cling to life on a drying and cooling world.
Mars is my favorite planet to observe when it nears its biannual opposition (and it's free of planet-encircling dust storms). This morning reminded me of the morning of June 9th, 2020, when I observed Mars for the first time through my FC-100DC, as it began to approach Earth that year. That morning, I was stunned to discern the southern icecap for the first time, along with dark albedo features that had never been visible to me before. It excited me to no end to realize how much more could be visible as the planet wheeled closer and closer to Earth that fall.
I have much the same feeling now. I truly can't wait to see what Mars will bring this year. I wonder what I'll be able to glimpse with telescopes that are a little better than those I had in 2020.
We've had plenty of clear skies lately - after a generally rainy spring - but the atmosphere has been so turbulent that I've rarely thought it worthwhile to take out a telescope. This week brought more of the same, but also something unique: a rare, close conjunction of Venus and Jupiter in the early morning sky. With the sky mostly clear, transparency quite good, and seeing a good deal worse than average, I woke up at around 5 AM last night and walked out with my Takahashi.
I wasn't sure where to go. Trees blocked the view of the planets from my backyard. Before our move, I might have walked to the park I like best, but that's 20 minutes away now. By the time I got there I figured the Sun would be too high in the sky - and I'd be painfully sore from carrying everything. I wandered in that general direction all the same, and then noticed a hill I usually pass while taking my kids to the playground. I decided to walk up the hill just in case - and, sure enough, by the time I got to the top I noticed two brilliant beacons just rising into view above the eastern horizon. Jupiter and Venus!
What a difference the new carbon fiber tripod makes! Walking with it is so much easier, and the FC-100DZ is much more stable now. After setting up I plugged in a 24mm Panoptic eyepiece - for a magnification of 33x - and took in the view.
I'm not a big conjunction guy - I care much more about seeing details on other worlds than I do about seeing those worlds appear close together - but it was pretty impressive to see both Jupiter and Venus in the same field of view. Although seeing was very poor and it was hard to make out much detail on either world, it was easy to get a sense of just how different they are from each other, and how diverse even our little Solar System really is. It certainly helped that three of Jupiter's moons were clearly visible, and that Venus was roughly halfway illuminated. I tried to take a customary blurry cellphone picture, and just by chance at that very moment a plane zipped in front of Jupiter.
As night turned to day, I packed up and walked home. When I returned to my backyard, I noticed that Jupiter and Venus were both clearly visible from a little spot near my fence. Maybe I hadn't needed to walk, after all? Still, there's always something magical about that hour before sunrise, when the city is still asleep and the loudest noises are often birdsong.
It's really hard to beat autumn in DC, and I'm trying my best to take advantage of every clear night. When conditions took a turn for the better tonight, I hurried out, Takahashi in hand, to the nearby park. Some kids were playing hide-and-seek nearby with flashlights - not exactly what you want when you're tired from playing with your own small children - but I didn't need dark-adapted eyes. I was out early enough to observe the waxing Moon and nearby Jupiter. I thought I'd already had the year's last glimpse of Jupiter; now I was determined to have one more look.
Jupiter was low enough in the sky to be tinted red by the thickening atmosphere, and in that corner of the sky seeing was mediocre at best. Still: I could clearly make out ruddy Io, just coming out from Jupiter's disk, with its shadow still on the planet. I couldn't believe my luck. I was able to observe such shadow transits for the first time last year, but I never had the chance this year - until the very last night I could view the planet.
The seeing wasn't good enough to reward prolonged study of Jupiter - and, to be honest, my much bigger TEC 140 has spoiled me a little with its more colorful and textured views of the planet. So I turned to the Moon, then illuminated perfectly around my favorite corner of the lunar surface: the area between the giant craters Plato and Copernicus.
Tonight I was especially struck by the length of the shadows in Plato, which are caused by the crater's mountainous rim. The shadows seem to be caused by mountains that must be higher and steeper than any on Earth. No wonder the Moon was widely considered before the Space Age to be a world of soaring mountains with the proportions of stalagmites in caves.
While the rim of Plato is lined with jagged peaks - remarkable, given that they're nearly four billion years old and would be ground to dust on Earth - they rise "only" around two kilometers above the lunar surface. That's far lower, of course, than Earth's tallest mountains. It's the low elevation of the Sun above the surface that casts shadows long enough to extend the entire 100-kilometer width of the crater. Some nineteenth-century astronomers thought those shadows flickered and thereby betrayed the presence of a lunar atmosphere; not the case, of course.
As I was disassembling the telescope, I happened to look up just as a fireball briefly illuminated the sky: a meteor quite possibly older even than Plato. It was a marvelous sight. I'm continually amazed at what you see just with the naked eye, if you take the time to occasionally glance at the night sky.
One last word on equipment. The Takahashi is beautiful and its optical quality is absolutely top notch, of course, but mechanically it is definitely a step below the TEC 140. The focuser and sliding dew shield, in particular, are just not quite as smooth and solid. I don't know that there's anything I'd change about the TEC, but the Takahashi has a few quirks here and there that I might address if given a chance. Still, it's a little powerhouse and once again acquitted itself well tonight.
We've had a few clear nights this week, with seeing and transparency both hovering near average. It's been a demanding month at work, but I had to step out last night, Takahashi in hand, to catch a glimpse of Jupiter and Saturn. The glare of the rising full Moon, however, discouraged me from going to the park near my house - it would just be too bright, I thought - so I popped up to my rooftop for a quick look.
That rooftop really isn't suited for serious observing. Somehow the concrete slabs thrum with vibrations from my building, and the warm air boiling from the rooftop always worsens the seeing, sometimes dramatically. Nevertheless I did steal a few clear, stable glimpses of Jupiter and Saturn: enough to make out countless zones and bands on Jupiter, and the Cassini Division on Saturn. The small, orange disk of volcanic Io, I believe, was just about to move across the Jovian clouds; I've been so overworked lately that I didn't bother to check.
Then I looked over at the Moon, still rising in the east. Like most observers, I always prefer the Moon when it's only partly illuminated - I love the shadows along craters and mountains - and in any case tonight it was clear that the atmosphere along the eastern horizon was just not going to cooperate. Seeing and transparency in that corner of the sky, it seemed, were particularly challenging. Still, the Moon is always - always - a striking sight through a fine refractor, no matter the state of the atmosphere.
After about fifteen minutes, I packed up and stepped back inside, thoroughly pleased that I'd ventured out despite my fatigue. It's almost always like that: even when tired, there are few things I'd rather do.
Conditions were glorious last night - temperatures in teens, seeing and transparency both above average - and I was feeling surprisingly energetic, so I dragged my TEC 140, DM-6, and Berlebach Uni tripod out the door, and walked 15 minutes to my favorite nearby park. I had about 80 pounds of gear with me, but somehow, last night, I found it quite manageable. It was heartening to know that I could transport the TEC 140 without much more difficulty than I used to haul about my dearly departed APM 140.
When I set up shop I noticed that the sky was strikingly dark, and that the stars and planets scarcely twinkled. I immediately plugged in my highest-power Delos eyepiece - which manages 217x - and targeted Jupiter. What a view! I lost track of how many cloud belts I could make out, and subtle detail was everywhere. I was looking at the same hemisphere I had admired about a week ago with the TEC 140, and that same barge I noticed then was still around. Now the Galilean moons looked even more clearly like disks, and therefore like real little worlds.
I decided that the difference between the TEC 140 and the APM 140 lies in the sensation of texture on the planets. More than the APM, the TEC gives me the feeling that the clouds of Jupiter, for example, have depth, which in turns makes it clearer that I'm observing a three-dimensional object. That really makes a profound difference. Both the APM and the TEC provide views that are far better than those of four-inch refractors, including the Takahashi FC-100DZ. There's just so much more contrast visible with the bigger refractors, and on a low-contrast object like Jupiter that means everything.
The view of Saturn was a bit less perfect, just like it was a week ago. While I could easily crank up my magnification past 200x on Jupiter - which is usually about the limit in the Washington, DC air - Saturn benefitted from lower magnification. Still, I was struck by the obvious complexity of its ring system in moments of good seeing. It seemed I could clearly make out not only the Cassini division, but at times I got a flicker of brightness variations, attesting to distinct ring groupings of varying brightness.
After observing Jupiter and Saturn for a while, I wheeled the telescope east to observe the Pleiades at low magnification, which was pleasant but not noticeably different than it is in a smaller refractor. Then I realized that Uranus had climbed well over the horizon, and in fact that it should now be near 37 Ari, a star of very comparable magnitude (5.75 to 6 for Uranus). I've never observed Uranus before. I've tried to find it, but come up empty time and time again. It's actually a little embarrassing; it shouldn't be that hard to identify. So, this time, with the weather perfect and armed with a powerhouse telescope, I decided to give it a try.
The trick was to find Menkar (Alpha Ceti) and Kaffaljidhma (Gamma Ceti) in the constellation Cetus. While these are bright stars - Menkar in particular, at magnitude 2.5 - it's telling that even with atmospheric transparency better than average, I could only barely make them out. DC's light pollution is especially bad to the southeast from my position, which is where the national mall and the rest of the city's downtown area is located. Anyway, once I found those two stars I used them to triangulate Mu Ceti, which at magnitude 4.25 truly was at the edge of my perception.
These three stars in Cetus formed a narrow triangle that pointed to Uranus and 37 Ari. In fact, the length of the triangle was actually greater than the distance of the planet from that triangle. Using my finderscope, I searched. And searched. About 20 minutes went by, and no dice: I could see only stars. I started scanning more broadly, thinking I'd done something wrong. Then I checked my star map - which I get through an app called Stellarium - and suddenly it hit me: I'd been looking for something that looked like a planet. But Uranus is so far away - and therefore so dim - that it should really be indistinguishable from a star at low magnifications. My problem was that I had plugged in my 24mm Panoptic eyepiece, which gave me a magnification of just about 40x. I needed to trust my map and really crank up the power on the star that, I knew, must be Uranus.
So I did. With the high power Delos eyepiece back in and my magnification at 217x, suddenly the planet became obvious: a little grey-green ball, wandering through space. I could make out, at most, only the subtlest detail on that little ball - and really it was virtually featureless. But the thought that that ball was four times the diameter of Earth gave me a rare, visceral sense of the scale of the Solar System. It can be hard to wrap your mind around the reality that the distance between Uranus and Saturn is actually greater than the distance between Saturn and the Sun. Now, at the eyepiece, it seemed obvious. I hadn't found Uranus before because I'd underestimated the size of the Solar System; I didn't imagine that a planet so big could look so small.
It might seem like a drawback of manual mounts that it took me over 20 minutes to find Uranus - not to mention the many times I've searched for the planet and failed. Nothing could be further from the truth. When you do "star-hop" successfully with a simple mount, the sensation of actually finding what you're looking for is really special, and you don't get that with a go-to mount. You also start to genuinely learn the sky; I'd never thought about the constellation Cetus, for example, but now I know where it is, and I know that its third-brightest star is actually a triple-star system that I'd like to check out someday. That's not to say that star-hopping is always feasible or desirable, especially in the big city. But, as usual, you do give something up by opting for the convenience of modern technology.
A last note on equipment: in recent days, I've ranked the Delos eyepieces, TEC 140, Orion 6x30 finder, DM-6, and Berlebach Uni tripod in comparison with other gear I've used. I've described them as the best I've seen in their class of equipment. Yet I haven't mentioned how well they all fit together. It really is seamless. The DM-6 holds the TEC 140 with perfect ease; there are no jitters, just buttery smooth movement even at high magnifications. The Uni tripod, while light, is an absolute rock, while the finder scope makes it a breeze to hop between stars. And the Delos eyepieces slotted in the TEC 140 provide a glorious view of just about everything. It's all very pricey, of course, but I really recommend this mix.
The walk home was arduous. But, like William Herschel exactly 240 years ago, I'd found a new planet, and that made it easily worthwhile.
We've had some wonderfully clear, autumnal nights over the past week, with Jupiter and Saturn riding high in the evening sky and the Moon waxing and waning nearby. I'm teaching what may be my favorite course at the moment - about the human history of nearby celestial bodies (what I call "neighboring worlds"), and a special highlight is taking my students out for a night with a telescope.
I have now accumulated some very fine refractors, however, and I worried about how they'd fare after being handled by twenty students. To that end, I drew on my research funds to buy a William Optics Zenithstar 81. It's a beautiful little refractor, and I figured that it would be more than adequate to give my students an impressive view of the Moon. For their first assignment, they need to find a feature on the Moon and then write a history of how people have understood, imagined, explored, or planned to exploit that feature.
A few things immediately struck me about the Zenithstar. First, it costs about a third as much as the TeleVue 85 I used to own - less than a third, when you consider it comes with its own mounting rings, dovetail, Bahtinov mask, and carrying case - despite giving up only four millimeters in aperture. Second, its build quality looks to be on par with the very best telescopes I own and have owned, with the possible exception of my TEC 140. Third, it seems to weigh less than the FS-60Q I once owned, and much less than the TV 85, and its sliding dew shield makes it much more compact than either telescope.
It was really easy to carry the telescope to a darker corner of campus, and there set it up on my DM-4 mount and Berlebach Report tripod. Almost immediately, the Plossl eyepieces I'd decided to use provided beautifully crisp views of the nearly fully illuminated Moon. The students who had started to gather were predictably impressed. When we found we had a few minutes to spare at the end of the evening, I decided to try showing them Jupiter and Saturn. At about 56x, the planets were small, but beautifully sharp and clear. Many of my students were awestruck; they had a hard time believing that they could really see the major cloud belts of Jupiter and the rings of Saturn from downtown DC.
Experiential learning is always special; it makes the otherwise abstract concepts we discuss in class come alive for my students, and it can provide lifelong memories. I for one was stunned by the performance of the little refractor. It is, by far, the most portable telescope I've owned, and when it comes to performance it really doesn't give up much to the TV 85. I loved my TV 85, but I would have a hard time recommending that telescope as a go-to instrument when the Zenithstar seems to provide so much more value for the cost.
Last night conditions were even better, and now I resolved to head out with my biggest telescope: the TEC 140. The weight of the telescope, tripod, and mount means that I really can't haul everything to my favorite field. I targeted the little alcove next to a church that I've used over the past year, yet when I arrived as I was dismayed to find that the church had installed a new streetlight that completely ruled out observing there. I wandered about, dragging my heavy gear, until I decided to head down to a little amphitheater near the National Cathedral. There I found a perch that, if I moved around a bit, afforded me a view of Jupiter, Saturn, and the Moon through the canopies of nearby trees.
When I swung the TEC to Saturn, I was mesmerized. This was only the second time I'd used the TEC, and the first time in good seeing. In those conditions, Saturn looked absolutely stunning, like a beautiful jewel set in a velvet background. Its many moons were brilliant and sharp, and the shadow of the planet on its rings gave me the rare sense that I was actually seeing a world in three dimensions (often, objects in the eyepiece look flat, and therefore two dimensional). Cloud details were obvious on the planet's yellow-white disk.
Switching over to Jupiter provided an even more spectacular revelation. The TEC provided what may have been my best-ever view of the planet, with more cloud belts and zones than I could count, delicate, feathery structures within those belts and zones, and a perfectly obvious, brown "barge" - an elongated, oval cloud feature - near the planet's equator. There was a contrast and vibrance to the planet's colors that you just don't get with a smaller refractor, and all four Galilean moons were visible as clear disks, rather than points of light.
Jupiter and Saturn soon wheeled behind the trees, so it was time for the waning gibbous Moon. Once again, I was dumbstruck. The Moon wasn't that far above the horizon, but at 163x there was just such a wealth of subtle, perfectly sharp detail, from jumbled crater peaks to winding rilles and delicate scarps. The terminator was perfectly positioned to throw mountain after mountain in sharp relief, and in exploring them I eventually lost track of time. Then a giant cricket jumped on my pants, I realized in shaking it off that it was past midnight, and I began packing up for the painful trek home.
The TEC 140, I have to say, is noticeably better than the APM 140 I've also raved about in these pages. I'm not sure it's worth the extra cost; certainly I could never have afforded the difference if I didn't use the telescope for my research and writing (which means I could draw from my research funds to buy it). I realize how lucky I am, and I hope I can keep using the telescope for a lifetime.
It won't be that often, however, until I manage to own a backyard; as wonderful as the telescope may be, it's also hard to transport more than a few minutes from our home.
We've had some clear skies over the past week, and of course for me that involved hauling my telescopes outside. With Jupiter and Saturn high above the horizon early in the evening, now is a great time for planetary observation. I set up my Takahashi FC-100DZ on our rooftop one night, but although it was convenient - and the National Mall looked spectacular in the distance - plumes of heat rising from our building marred the view. Jupiter was a boiling mess, and Saturn looked only slightly better.
Smoke from the west coast wildfires moved in early this week, so the transparency of the sky plummeted. Yet seeing was above-average, and - knowing that a little haze in the sky can sometimes improve planetary views - I stepped out anyway, Takahashi in hand. I mount the telescope on a DiscMounts DM-4, and although the mount should easily be able to hold the Takahashi with minimal vibration, so far its stability doesn't compare to that of the AYO II I recently sold - even on my heaviest tripod. Perhaps I need to play around with the tension? I suppose I'll keep experimenting.
I wasn't prepared for the thickness of the wildfire smoke at high altitude - yes, that's more than a little depressing - and so Jupiter and especially Saturn were dimmer than I'd anticipated. Yet seeing was, at times, phenomenal. All of Jupiter's moons were visible, and all looked like clear disks of varying color and size. Orange Io and giant Ganymede were especially easy to pick out at 177x, and for once I wished I had more magnification (unfortunately, I'd left my Nagler zoom eyepiece at home).
On nights of bad seeing, one two dark belts can be visible on Jupiter. Now, I saw some spectacular detail. Not only were the two northern and two southern temperate belts plainly visible, but I could make out delicate, at times feathery texture all along each belt. I lingered a while on that view. Saturn, unfortunately, was less impressive: the smoke was just too thick to permit more than a dim view.
On a night with higher transparency, I walked out with my EVScope. I confirmed what I'd long suspected: in a light-polluted urban sky, brightening at the edges of the view precludes long exposures. While you can still get impressive urban (!) views of many nebulae, star clusters, and galaxies, the telescope performs much better when the light pollution isn't as bad.
The comparison above shows what the EVScope can do under a suburban sky (top) and in ideal conditions under an urban sky (bottom), with similar exposure times. It should be stressed that conditions for the bottom image were truly ideal: the nebula was near zenith, there was no Moon, and transparency was excellent. Still, it's clear that the telescope goes a bit deeper when the light pollution is lower. Of course, I also could have had a much longer exposure under that suburban sky, had I wanted to do that.
All in all, two good nights of very different observing - and one pleasant view from our rooftop.
Everybody approaches amateur astronomy in different ways, but for me - and many others - the most difficult thing about the hobby is that you always wonder, no matter how sublime the view: what would I see if I had different equipment? Usually "what would I see" means "what more would I see," and usually "different" means "just a bit better" - and that means that many amateur astronomers, at least at some point, embark on a long, frustrating, painfully expensive quest for new telescopes, new mounts, new tripods, new eyepieces . . . the list goes on.
I've been on that path for quite a few years now. Yet when it comes to telescopes - or more specifically, to optical tube assemblies - I reached the end this spring. For a long time, I dreamed of someday - somehow - being able to own a truly world-class, medium-sized refractor. I long had my eye on the Telescope Engineering Company (TEC) 140: an American-made, oil-spaced triplet of uncompromising optical and mechanical quality that, while portable, easily outperformed much larger telescopes. I didn't think I'd be able to afford it for a very long time, but then I realized that although I'd slowly cobbled together a rather large collection of telescopes, I was really only using three of them (my EVScope, Takahashi FC-100, and APM 140). If I sold my unused telescopes and some other gear for the right price, I might just have the financial foundation I needed to pursue a used TEC 140.
Precisely as those thoughts entered my mind, a TEC 140 ED in like-new condition popped up on the used market for a daunting but reasonable price. I took the plunge, and then went on a truly exhausting campaign to sell everything I could spare to recoup what I'd spent. Some of what I sold, I know I will miss for a long time. I ended up parting with my FS-60Q, TV-85, and APM-140, and each loss stings in a slightly different way. I've had unforgettable memories with the TV-85 and APM-140 in particular, but upgrading equipment is not for the sentimental.
In the end I earned precisely as much money as I spent on the TEC 140, so my guilt was mostly assuaged when it arrived. Comparing it to the APM 140 was instructive and ended up highlighting the virtues of both telescopes. The TEC 140 is, first and foremost, slightly but meaningfully heaver and bulkier than the APM 140. Its focuser is more robust, its finish is of clearly higher quality, and its tube ringers are easier to manipulate. With that said, the APM's focuser is just as buttery smooth, and I actually find its sliding few shield a little easier to manipulate. It's not a tossup - the TEC 140 is clearly mechanically superior - but the APM holds up surprisingly well when you consider that it costs less than half as much (during sales, more like a third as much).
Because the TEC 140 is that much bulkier than the APM 140 and uses a Losmandy dovetail that I didn't want to replace, I needed a new, sturdier mount. That's also because my AYO II mount had, after just a year, started to develop an unacceptable amount of slippage on one side. So, I scraped together what I could and purchased a DM-6 mount to match the DM-4 I purchased for my Takahashi. This, to be sure, is a beautiful piece of metal . . . but although mechanically superior to the AYO II (in my view), it's also very substantially heavier. The upshot is that my TEC 140 setup is a good deal less portable than my APM 140 setup had been.
Because it's less portable, I can't take the TEC 140 to the field where I used to set up my APM. That field will be reserved for my FC-100DZ and EVScope from now on. On some level it feels like a minor loss - I had some wonderful times there with my APM - but I'm quite sure the FC-100 can pick up the slack. And I do now have the alcove, near the church by my home, that affords some fine views of the southern sky.
The TEC-140 is also so heavy that I refuse to take it out unless seeing is above average. This morning, for the first time in a while, it was forecast to be. So there I was, huffing and puffing on the sidewalk at 4:00 AM, bound for the alcove and for a date with Jupiter and Saturn. Both planets have passed behind the Sun and are again high enough above the horizon to be worth a look.
It was an exhausting walk, but setup was easy and quick as usual. When I turned to Jupiter, two things struck me. First, seeing was not nearly as good as advertised; that close to the southeastern horizon, it was average at best. Second, the color correction of the telescope was absolutely spot on. The older TEC 140 ED is supposed to be slightly better in longer (red) wavelengths than the newer TEC 140 FL, but slightly worse on shorter (blue) wavelengths, which should make the ED somewhat better for observing Mars and Jupiter, but somewhat worse for astrophotography. In any case, Jupiter's coloration was lovely, even if the planet's fine detail was often obscured by the turbulent atmosphere.
Saturn, fortunately, was higher in the morning sky. Turning to the planet at 98x, with a 10mm Delos eyepiece installed, made for a genuine "wow" moment. Never have I seen more than a few of Saturn's moons, but now Enceladus, Dione, Titan, Tethys, and Rhea were all clearly visible. Subtle gray shading was easy to see on the planet's disk, as was a shadow just behind the rings (I love their orientation right now). The Cassini Division was plainly obvious but now around the entire ring system; unfortunately, seeing was just not good enough to see more. Once again, the color correction was sublime.
After turning to some stars and observing them in and out of focus, it was clear to me that the telescope has - surprise, surprise - exceptional, beautifully corrected optics. Yet it struck me, as it did several months ago with the FC-100DZ, how much more seeing matters than optics when it comes to planetary observation. Did I see more detail this morning on Jupiter and Saturn with the TEC 140 than I would have with the APM 140? Maybe, just a little. But have I seen more detail with the APM 140 when the atmosphere cooperated? Absolutely. I'm looking forward to experiencing what the TEC 140 can do when the atmosphere truly is steady.
I suspect I will miss the portability of the APM 140, and wow that is a good telescope when you consider its cost relative to the TEC 140. Yet for me, it is important to know that the quality of my optics are not keeping me from seeing more planetary or lunar detail. With that in mind, I am very happy with my beautiful TEC. A distant goal, accomplished surprisingly soon!
I was quite tired after I last published on this blog, but the night of the tenth was clear again - and again the seeing promised to be better than average. With a week of uninterrupted rain coming our way, I had to step out again. This time I decided to try our rooftop, which was been a little too crowded to feel safe lately.
I decided to see whether the APM 140 was portable enough to haul upstairs. To my astonishment, the telescope slipped easily into the Gitzo carrying bag that I've been using for my Vixen refractor. That sliding dew shield goes a long way. It also barely felt heavier, and it suddenly dawned on me that, because the APM can sit well on the same mount and tripod, it's actually just as portable as the Vixen. Imagine that: a nearly six-inch-wide, portable refractor!
To my relief, the rooftop was relatively empty. I unpacked and set up the telescope in under five minutes, and of course the APM acclimates so fast that it was immediately ready to go. Jupiter was up first. To my delight, I'd tuned in on time for another shadow transit - my third in three weeks! To think I'd never seen one before. This time it was plainly obvious that it was Io's shadow on the Jovian clouds; I could clearly make out the moon as a tiny orange disk. How the mind soars to imagine its volcanoes belching sulfur into the radioactive torus swirling around Jupiter.
I switched to Saturn, but the planet was just a bit lower in the sky than Jupiter, and the difference in seeing was plainly noticeable. Turning back to Jupiter, I was struck by how much better - I'm afraid there's no other word for it - the planet looks through the APM than it does through the Takahashi FC-100DC, even when the smaller telescope has its focal extender screwed in. The biggest difference, I find, is in the color. Jupiter's reds typically look a pale pink through the Takahashi, but they are clearly red - in the case of the Great Red Spot, a vivid crimson - through the APM.
I also noticed that my Delos eyepieces offered a notably better view then the Naglers, for what it's worth. Both made by the same company, of course, but the Delos seemed to have just a bit more contrast, and they were definitely easier on the eye to use. I'm thinking now that I should swap my 9mm Nagler for a 10mm Delos, if I can do it while breaking close to even.
As I admired Jupiter with the 6mm Delos screwed in, for a magnification of 163x, the seeing suddenly stabilized for around 20 seconds, and the planet suddenly snapped into crystal-clear focus. I was taken aback; I almost couldn't believe what I could make out. It was a textbook view of the planet - in that it could have literally appeared as a Hubble photograph in a textbook, held at arm's length, while squinting ever so slightly. The Great Red Spot and the swirling, complicated clouds surrounding it beautifully framed Io's shadow, and the details in the cloud belts were so richly textured . . . I was just astonished.
When the seeing returned to normal, I could do nothing but pack up and leave. There are times in amateur, observational astronomy when you've had your fill and you need to step away to process it for a while. I packed up - again, in under five minutes - and stepped quietly downstairs, knowing I was sated for the week.
A note on the APM. Earlier this year, I would not have believed such a telescope was possible - or at least, I would not have believed I would ever own one. Here is a refractor that, at 5.5 inches in aperture, excels at just about every object, but somehow manages to be grab-and-go portable. It weighs just a few pounds more than my much smaller Vixen - which is itself light for its aperture - and so a relatively light mount and tripod can comfortably handle it. I can carry it with ease. Its focal length is fast enough for wide-field views, but slow enough for magnificent planetary observation. It offers absolutely sharp, color-free views and first-class mechanical quality, at least on par with my Takahashi, but somehow costs just a hair more than that much smaller refractor - and about the same as the Vixen. Somehow, it cools down just about as fast as they do.
It's true that my APM has what I gather is an unusually high strehl ratio - in other words, its optical quality is better than average - so my experience with this model might be unusually good. Even so, tonight's look at Jupiter - not exactly the easiest object to view - made me wonder why anyone would need or want anything more expensive at this aperture. My cup was full, and I can't imagine that any other portable telescope would have filled it further.