For amateur astronomers, two things happen to the atmosphere around this time of year in Washington, DC: in general, transparency improves, and seeing - meaning, of course, stability - deteriorates. Daytime brings deep blues, sunset a beautiful gradient from azure to scarlet, and nighttime brilliant winter stars in a velvet tapestry (when not facing towards the National Mall, at least). At the same time, the stars noticeably twinkle far more than they do in summer, and moments of steady seeing become ever rarer. The muggy, mosquito-plagued nights of summer, when the planets can very occasionally look like little Hubble photos viewed from afar, are now a distant memory.
All the same, since keeping this blog I've found autumn to be my favorite time to observe. It's just so much more comfortable being outside, the planets are still high in the sky, and my refractors at least give me a puncher's chance of making out some detail on them, even in nights of mediocre seeing.
With that in mind, I stepped out on the 14th, Takahashi in hand, and found a nook near my mostly tree-covered backyard that afforded me a good view of Mars. It was cold by DC standards - around freezing - but my telescope was well acclimated and the view was beautifully sharp. The Martian south pole in particular looked large and sort of smeared; not quite as brilliant as it can, but larger in dimensions. Later, a spectacular set of pictures posted by Peter Gorczynski over at CloudyNights.com revealed the cause: a swirl of clouds around the pole that were barely visible to me in the mediocre seeing.
I didn't last long in the cold weather, and over the next week seeing here in DC grew worse - but transparency remained better than average. I decided to test out the Unistellar EVScope 2 on the comparatively few but spectacular deep space objects that are beginning to climb high above the horizon in our late autumn sky.
On the 22nd, I marched about 20 minutes uphill from my house to my daughter's school. Its field is now the nearest I know that is not completely saturated with light, and I can only hope it stays that way. It's not hard to haul the EVScope that distance, thanks to the relatively ergonomic backpack it comes with, and I can only emphasize yet again how absurdly easy it is to set up the telescope once I'm in position.
It takes no more than a minute to have the EVScope fully aligned and tracking my first target. It quickly and easily hooks into its tripod, immediately connects to my phone, and in just moments aligns with the night sky and slews to my first target. It takes me two or three times longer to set up my refractors on their sample manual mounts, which of course don't have any software at all. Other tracking amounts, even the simplest ones (such as the iOptron AZ Mount Pro I own), require far more steps to set up, and often don't quite align perfectly; it's why I inevitably favor manual mounts when stepping out with my refractors. I'm not sure how Unistellar leapfrogged all the established brands in amateur astronomy by offering a mount that truly is plug and play - but they have, and it's wonderful.
After I let the telescope cool down, I turned to the Orion Nebula. In the past, I've tended to focus too much on my phone while the telescope slowly integrated its pictures and the view of my target gradually brightened. This time I favored the eyepiece, which as I've written elsewhere is much improved on the EvScope 2. I now noticed that the eyepiece view seemed much sharper and, to my surprise, three-dimensional than the image on my phone. The dark nebula jutting in front of the familiar crescent of the Orion Nebula, for example, truly looked as though it was in the foreground, and I followed a fascinating zigzag pattern of dark nebulosity weaving across the bright core that mostly washed out in the phone image.
The EVScope permits easy if relatively low-resolution astrophotography, but the current iteration at least is really designed for observing. I've complained that using the EVScope is a very different experience from using a traditional telescope, because I've tended to wait around for the images to integrate on my phone. This time, I was glued to the eyepiece - and it really did feel like a proper observing experience.
The EVScope 2 improves considerably over its predecessor, and the Unistellar software has continually added new capabilities. Just have a look at the image of the Orion Nebula that I took almost exactly two years ago, and compare it with this week's version. I suspect I could further improve the view through the EVScope 2, and I wonder what it would look like were I truly under a dark sky. Still, I find the progress to be really exciting.
Just last night, I learned that Unistellar had released yet another software update: this time to enable planetary observation. I couldn't resist, and marched back to the same field. This time, however, I was a little disappointed. While the telescope for the first time automatically dimmed its images of Jupiter and Mars and showed real details on both worlds, overall the view was of course radically different from what I see through my refractors. While traditional telescopes may not as clearly reveal the cloud bands of Jupiter, for example, they show far finer and subtler detail; far more realistic and impressive coloration; and of course the moons and stars surrounding the planets.
I expected as much, but in the moment I couldn't help but be underwhelmed. Yet while walking home, I considered where the technology might be in another two years. Eventually, I suspect there will be few if any areas where traditional telescopes reign supreme. To me, their greatest value could then lie in the connection they provide to generations of observers stretching back to Galileo: to a history of often-eccentric women and men straining at odd hours to discern barely perceptible truths hidden across unimaginable distances in time and space. There are some things clever software can never replace - not many, perhaps, but some.
Autumn came early this year in Washington DC, yet the relative warmth of early autumn lingered well past its usual expiration date. The mosquitoes lingered with it, even if their population fell with the leaves, but overall it's been a gorgeous month in the city. Over the past week, we had three crisp, clear nights with tolerably good seeing and transparency. With the canopies above my yard increasingly bare, I was able to peak through and branches and observe without hauling heavy gear for twenty exhausting minutes.
A few nights ago, I rolled out my TEC 140 to observe the Moon and Jupiter. Night comes early at this time of the year, of course, so I made it outside before my six-year-old daughter's bedtime. I asked her to join me, and when she did she was thrilled to make out craters on the Moon and, with some difficulty, cloud bands on Jupiter. To my surprise, those were unusually difficult to make out. The sky had a milky quality around bright objects, a kind of watercolor softness, that seemed to obscure detail on the likes of Jupiter. Still, a memorable experience for daughter and daddy alike.
On November 8th, conditions promised to be marginally better, and temperatures were just about ideal. This time, I stepped out with a much lighter setup: my Takahashi FC-100DZ, clamped to the CT-20 mount that I'd screwed into my Berlebach Uni tripod. It's a more robust outfit than I take to the local park, but it's still easy to move all in one go.
A quick aside: the exceptional weight of the DM-6 mount can make it really sturdy and capable of handling surprisingly hefty telescopes. Yet it also ruins the portability of my TEC 140. The mount feels at least as heavy as the telescope, and when yoked to a tripod it's a chore to move even without the telescope attached. Another problem is that attaching the telescope to the DM-6 mount is a heart-stopping experience in the dark. It's hard to be sure that the dovetail is actually in the clamp, and I've now been unpleasantly surprised several times when the telescope suddenly lurched down after I thought I'd got it in. I live in fear that on some sad night I'll misjudge it, step away, and watch in horror as the telescope crashes to the ground.
I have no such problem with the Takahashi. Yet the lightness of the CT-20 mount does mean that the telescope tends to tilt - even when perfectly balanced - if objects are too close to zenith. The CT-20 has an answer, however: it's easy to adjust the tension in the altitude and azimuth axes. This can mean that there's too much tension to easily nudge the telescope along when observing objects that are high up in the sky, but I'll take the tradeoff: less weight and less hassle is worth some compromise.
In any case, the Takahashi gave me some very satisfactory views of the waning but still nearly full Moon. The view along the emerging terminator in particular was quite striking, while the Moon's fully illuminated surface showed a mesmerizing swirl of subtle grey shadings. The rays streaking from Tycho, one of the youngest big craters on the lunar surface, are always impressive when the Moon is this close to full.
Yet Mars is now wheeling towards its biannual opposition, so of course it stole the show. The planet is quite high in the sky by around 10 PM EST, and it's already brighter than any celestial body visible at that time save Jupiter and the Moon. I feel that its color even by naked eye is not quite as blood-red as it was two years ago; it's paler and a little closer to orange.
The Takahashi revealed its waxing globe, but showed considerably less contrast than I could make out a couple years back. In moments of good seeing I could make out the south polar icecap, and then a dark albedo swirl around the ice, interrupted by lighter land before continuing towards the north. Yet the view was anything but sharp, and the planet seemed unsteady somehow in the mediocre seeing. Part of the problem is that much of Mars is currently obscured by bright dust storm: a common if frustrating occurrence when Mars makes a close approach to the Sun.
It was to gain a clearer view of the Moon and Mars that I stepped out last night with the TEC 140. Conditions seemed about the same, except it was colder and the reappearance of a halo around the Moon suggested that transparency would be lower. The TEC takes meaningly longer to cool down than the Takahashi, although in both cases the Delos eyepieces take longer to acclimate than the telescopes. I'm not sure it's widely understood that compound eyepieces take longer to cool down than, say, Plossl eyepieces - but that's certainly been my experience, and it does stand to reason. There's just a lot of glass in those things.
In any case, both refractors and their eyepieces need only a few minutes to give acceptable views, even if they do take longer to fully acclimate. When everything was ready I was surprised to find that the TEC 140 actually provided slightly softer views than the Takahashi did the other night, even if contrast on Mars in particular seemed just a bit higher, and the Moon's terminator at times snapped into exquisite if fleeting focus. I was once again impressed by the Takahashi; despite its compact size, I rarely feel I'm missing out when I use that telescope, the way I did with many other small telescopes I've owned. It punches far above it weight.
Yet to me the bigger takeaway was that the difference between telescopes is often completely swamped by atmospheric conditions. In mediocre seeing and transparency, there really isn't much of a divide between the $8000 (!) TEC 140 and the $3000 Takahashi (of course both telescopes have world-class optics; even in bad seeing, I would suspect a meaningful difference between them and a run-of-the-mill refractor). In my years of observing here in DC, I can probably count on one hand the nights on which the atmosphere was so stable and clear that I could use magnifications of 200x or more. The pricey difference between optics is often less apparent here than it would be elsewhere, and I think that's something observers should acknowledge more often. Where you live will dictate the gains you get by spending more on bigger and fancier telescopes.
William Sheehan - who publishes some of the most engaging books on the history and practice of planetary and lunar observing - writes that as an observer views Mars near opposition, "over it, intermittently, uncertain details dart and then are gone like doubtful visions." None other than Percival Lowell - a key popularizer of the Mars canal theory, among other things - coined the term "revelation peeps" to describe these sudden glimpses of intricate detail.
That is precisely what Mars had on offer tonight. It wobbled and wavered, like a coin seen through the burbling water of a fountain. Then, for fractions of a second, it snapped into sharp relief, looking really and truly like a planet seen from an approaching spaceship. Just before my brain could grapple with that new reality, the planet reverted so quickly to an indistinct blob that I could scarcely believe it had ever been otherwise.
Mars! Always so difficult, but oh so compelling.