Archive for October, 2012


Observing report: the compleat stargazing session

October 22, 2012

Saturday night London and I met up with David DeLano at the Salton Sea for an evening observing session. In thinking about how to describe it I decided that it was the compleat observing run–and yes, I mean compleat, meaning total or quintessential, not ‘complete’.

For one thing, we observed almost every class of object out there: artificial satellites, meteors, the moon, a planet and its moons (Jupiter), a comet (Hergenrother), double stars, asterisms, planetary nebulae (the Ring and the Dumbbell), a supernova remnant (Crab Nebula), bright diffuse nebulae (M42 and M43 in Orion), binocular associations (Alpha Persei Association and Hyades), open star clusters near (Pleiades) and far (M35-38, among many others) and very far (NGC 2158), a very dense open cluster (M11, the Wild Duck cluster), a very sparse globular cluster (M71 in Sagitta), a showpiece globular (M13, the Great Glob in Hercules), a non-Messier glob (NGC 288), Local Group galaxies (M31 and M33) and satellite galaxies (M32 and M110), and at least one non-Messier galaxy (NGC 253, the Silver Coin). Okay, so we didn’t track down any asteroids, terrestrial planets, dark nebulae, Milky Way star clouds, or galaxy clusters. Still, I think we did okay for a sunset-to-midnight run, especially considering we had no fixed plan beyond “hang out and look at stuff”.

Also, we used almost every class of common astronomical instrument: naked eyes, binoculars, doublet refractors (David’s Galileoscope and my SV50), a triplet refractor (David’s SW100T), a Newtonian reflector (London’s Astroscan), and a catadioptric scope (my Apex 127 Mak), in apertures from two to five inches and focal ratios from f/4 to f/12.

We spent a lot of time just looking up. We used whatever instruments we had to hand, on whatever targets were of interest. We used rich-field scopes on solar system targets and planet killers on the deep sky and located faint nebulae with binoculars. We compared views, compared eyepieces, and compared objects. We found new stuff, checked maps, and got lost–yes, both of us. We explored. We rocked.

I did not log any new Herschel 400 objects. I did have a fantastic time. In the future when I am looking forward to an observing run, my standard will be, “I hope it’s as much fun as that one night at the Salton Sea with David”.

I’ve done a LOT of observing this month, with two Mount Baldy runs and overnight trips to Joshua Tree, the All-Arizona Star Party, and the Salton Sea. Also, I’ve been fortunate to get to observe with three of the 10MA regulars in that time (David DeLano, Terry Nakazono, and Doug Rennie). Partly I’ve been making up for lost time, since it was too darned hot to go camping before October this year, and I was too busy in previous months anyway. It’s going to wind down now for a bit, though–this coming weekend I’m out of town, and three weekends from now we’ll be celebrating London’s 8th birthday.

I’ve been in a reflective mood already, as I passed my fifth anniversary as a stargazer and as I approach my 400th observing session. That really kicked into gear when Richard Sutherland asked me in a comment if I had any big plans for the next five years. I’m not ready to tackle a subject that big just yet, but I have learned a few things in this month of crazy observing:

  1. The moon is not nearly as much of a hindrance to deep-sky observing as I used to think. Yes, it gets a lot darker when the moon goes down–David and I were both struck by this Saturday night. But Doug and I swept up a ton of faint fuzzies in binos and in his SkyScanner despite a moon only about three days from full.
  2. Two inches of aperture will take you crazy deep under dark skies. By using every trick in the book–fanatical dark-adaptation, staying up past midnight (when most folks turn their house lights off), observing at the zenith, waiting until after a rain had swept the crud out of the skies, and mildly hyperventilating–I was once able to spot M1, the Crab Nebula, from my driveway using my 15×70 binos. At the Salton Sea two nights ago, it was dead easy in direct vision in the 10x50s, and in our 50mm finder scopes. M32 and M110 were also dead easy in the Galileoscope, and more difficult but still doable in the binos, with the difficulty mainly down to lower magnification and therefore smaller image scale.
  3. With the right eyepiece, the XT10 is a pretty decent rich-field scope. I got the XT10 back in 2010. It came with a 2″ focuser, but until this summer I had not invested in any 2″ eyepieces; I was loathe to spend any money on an eyepiece that I could only use in one scope. But this summer I caved and bought a 32mm Astro-Tech Titan. With a 70-degree apparent field, it gives a true field of almost two degrees in the XT10–enough to frame the Pleiades, the Double Cluster, the Andromeda Galaxy and both satellites, or the entire sword of Orion. That is an 80% gain in the area of the true field of view over my widest 1.25″ eyepiece. David DeLano also has one for his SW100T and it is a fantastic eyepiece in that scope as well. The 32mm Titan normally runs about $80, and IMHO it’s a steal at that price, but right now it’s on sale for closer to $60. If you have a scope with a 2″ focuser, what are you waiting for?
  4. For regular camping, a scope you can pick up and move around is highly desirable. At both Joshua Tree and the Salton Sea, I was happy to have the Apex 127 along, because I could just pick it up and move it to get away from local lights or trees. I will have to keep this in mind in contemplating future scope purchases. I have to admit that I am interested in the Celestron C8 SCT, partly for historical reasons, partly because it is the biggest scope that will ride comfortably on my SkyWatcher AZ4 mount (= Orion VersaGo II), and partly because it is probably the biggest scope I could just pick up and move around without a second thought. I reckon I’ll have the Apex 127 forever, though, even if I get a C8 someday, for the same reason that I’ll keep the XT10 if I get a bigger dob–for what it does, it’s just about perfect.
  5. Accessories matter. For the first time ever, I have spent more money on accessories than on scopes this year. This summer I went nuts and bought some nice eyepieces, and I just ordered some tube and finder rings and a dovetail for the Apex 127 and SV50. Observing is a lot easier when stuff Just Works, and most telescopes Just Work better with better accessories–sturdier mounts, better diagonals and eyepieces, more convenient finders, and so on.
  6. My interests are changing. I’ve only done a handful of comet sketches, but I’m digging them. I’m getting kinda excited about the idea of sketching deep-sky objects. I’m also getting more interested in trying to understand the 3D structure of what’s out there. Before this past month, I hadn’t done any serious binocular astronomy in over a year, and it’s really been great to get back to that. I have no idea where I’m going yet, but it is probably going to involve a lot more than tracking down the next hundred LTGs*.

* Little Turd Galaxies.

The most exciting development in the past month? The morning after the All-Arizona Star Party, Jimmy Ray said that London was pointing his Astroscan around with sufficient skill that he could probably earn a certificate at next spring’s All-Arizona Messier Marathon (certificates start at 50 objects). I had not even considered this possibility, but I discussed it with London on the drive home. Actually being able to find stuff with his telescope the past two weekends has been very empowering for him, and he wants to give it a shot, so we’ll probably start practicing in the coming weeks and months. Fingers firmly crossed!


Comet Hergenrother again

October 18, 2012


Observing Report: All-Arizona Star Party 2012

October 17, 2012

The 10MA crew at AASP ’12. From left: me with my XT10, David DeLano with his SkyWatcher 100T, London with his AstroScan, and Terry Nakazono.

Last Saturday night London and I were out in Arizona for the 2012 All-Arizona Star Party. We’d been to the 2010 AASP–one of the finest nights of stargazing of my life–but we missed it last year, so it was great to get back out there. Terry Nakazono went with us. It was our third time observing together after a couple of Mt. Baldy runs this summer, and our first time under truly dark skies.

Happiness is a new scope under dark skies!

The big news for us was meeting frequent 10MA commenter David DeLano for the first time. David and I have been email pen pals for a couple of years now, and he’s written a couple of guest posts (sun funnel and diagonal comparison) but we’d never met in person before this weekend. He’s not unusually happy in this picture–in my admittedly limited experience, his grin is as much a feature of his face as his moustache. But he is pretty darned happy, because he was rolling with his dream scope this weekend, a 4″ f/10 SkyWatcher triplet apo that he’s owned for just a couple of months. This was only his third or fourth time using it, and the first time under dark skies.

Terry’s new Celestron NexStar 102GT–a.k.a. the Costco Scope. Photo by Terry Nakazono.

As luck would have it, Terry was also rolling with a new “big gun”, and it was also a 4″ f/10 refractor. His is an achromat, the Celestron NexStar 102GT, which he acquired even more recently. He calls it the “Costco Scope”, because apparently this particular package of scope and mount is only available in Costco stores. It’s a 4″ long-focus achromat on a fully motorized GoTo mount for $200 even, which is probably one of the best deals in telescopes right now. Terry showed me Barnard’s Galaxy and IC 342, another faint galaxy, through this scope, and I can confirm that it both pulls down the photons and gives a nice crisp view.

Loaded for bear. The padded grocery sack on the left covers the end of the XT10 so it doesn’t get dinged when I close the hatch. Photo by Terry Nakazono.

With Terry’s new scope and tripod–not to mention his tent and the rest of his gear–London’s AstroScan, my XT10, assorted camp chairs and sleeping bags and backpacks and water bottles and so on, our Mazda 5 was packed pretty full. Terry snapped this pic when we stopped for gas in Blythe.

The AASP was not just a chance to hang out with new friends but also to catch up with an old one. I hadn’t seen Darrell Spencer (on the left here, checking out David’s SkyWatcher) since the 2010 AASP, although we’d emailed back and forth a few times. It was great to see him again–and kinda funny, too. Not much had changed. He was rolling with his 11″ Celestron SCT and I had my XT10, just like last time. He was working on the Herschel II list and I was chasing Herschel 400 objects, just like last time. He’s closer to finishing his list, though, with only 25 or so objects left. Meanwhile I’ve just barely passed the 150 mark on the Herschel 400.

Darrell was already set up when we rolled in, and he invited us to set up to the south of his camp. Next to him was Jimmy Ray (just visible here between Darrell and David), who quickly hit it off with our crew. Darrell and Jimmy also shared their experience with us, which was a real boon, especially for Terry as he was still learning the ropes of his first GoTo scope.

Oh, about that GoTo scope. Up until now Terry has been working almost exclusively with tabletop Dobsonian reflectors. His first scope on getting back into astronomy in the past couple of years was an Orion Funscope, and his most-used scope is his SkyScanner 100 (see his review here). With the SkyScanner 100 and more recently a StarBlast 4.5, he has logged over 400 deep-sky objects, mostly galaxies. To put this into perspective, in five years of stargazing I have observed perhaps 350 deep-sky objects, mostly with a 10″ scope. So it’s quite an achievement, and one I hope I can convince Terry to write up as a guest post.

Anyway, my point is that going from small reflectors with no electronics to a big GoTo refractor is quite a change of pace. I asked Terry how it came about and he pointed to two major factors. First, the scope is a heck of a deal and he was curious about it. Second, and more importantly, after logging 400 DSOs by starhopping with small reflectors, he felt he had earned a break. I couldn’t agree more.

A few low clouds skirted the western and northern horizon around sunset, but they didn’t last, and the skies were cloud-free all night long. Transparency was good but not incredible. Jimmy said he could see the Gegenschein and pointed it out to Darrell and me, but neither of us was fully convinced. I’m not saying Jimmy didn’t see the Gegenschein, but I didn’t see anything I felt comfortable calling the Gegenschein. That could be inexperience on my part, and it could be imperfect vision, too. London regularly sees things in the sky that I just can’t make out. But it was also at least partly imperfect transparency.

(Now, I should qualify that by pointing out that the skies here in Claremont are essentially never as clear as the sky was at the AASP Saturday night. The transparency was only imperfect by the standards of the remote Arizona desert, where on the clearest nights it seems that there is no atmosphere whatsoever between you and the stars.)

The western sky was striped with delicate crepuscular rays after sunset (also just like last time).

One of my major goals for the night was finding and sketching comet 168P/Hergenrother, a dim periodic comet that unexpectedly brightened by a factor of 100 recently. It’s a tough catch from town–earlier this week I caught it from my driveway with the XT10, but only by waiting until it was high in the sky, knowing exactly where to look, and using averted vision. But under dark desert skies it’s dead easy, and shows a bright nucleus and wide tail even at low magnification. Comet Hergenrother is also moving at a decent clip–as the sketch shows, it moves visibly in the space of an hour.

I found the comet by sweeping northeastern Pegasus at low power, and sketched the field without taking the time to figure out exactly where I was. I thought I could work that out later, using Stellarium, and I was right. The right part of the above image is a screenshot from Stellarium, inverted and annotated in GIMP, to show the field of the comet. Hergenrother is still visible–check Heavens Above or google ‘comet Hergenrother chart’ for finder charts. Update: the best Hergenrother charts I have found so far are at Skyhound and AstroBob. The Skyhound chart covers more days, but the AstroBob chart goes deeper, and those dim little stars are clutch if you’re trying to find the comet under less-than-perfect skies. The Heavens Above charts are great but AFAICT they only show the position of the comet right now, so there is no provision for printing out a chart for this evening (and the comet will have moved in the meantime).

I chased the comet, I traded views with my fellow stargazers–including London, who found the Pleiades by himself with his AstroScan–and I hunted down a bunch of new Herschel objects. But my favorite views of the night were the unexpected ones.

First were the meteors. Holy smokes did I see a ton of them. I lost count around three dozen. One of the best came when Terry and London and I were walking David to his car–a brilliant meteor shot across the western sky and left a glowing trail that slowly faded. I almost missed the best meteor of the night, though. Around 1:30 in the morning I was looking down to check my charts when I saw bright light flashing in my peripheral vision. I looked up in time to see a fireball shooting straight down toward the northern horizon. It was so bright it cast shadows on the ground–something I had read about but never seen before. Update: David pointed out via email that the Orionid meteor shower peaks this weekend, and the meteors we saw last weekend were probably advance scouts from that swarm.

From midnight to 1:00 AM I took a little siesta. I reclined in the lounge chair with my 10×50 binos and split my time between dozing, scanning with the binos, and just looking up in wonder. The Milky Way shone from one horizon to the other like an arch supporting the dome of the heavens. But ironically it was the “dome of the heavens” I was trying to escape.

Shattering the Bowl of the Sky

I haven’t talk much with others about this, so I don’t know how common it is, but for me one of the hardest things about space is perceiving it as space. It is very, very easy to look up and see the sky as a dome set on top of one’s little patch of the Earth like a bell jar. It is much harder, for me at least, to keep in mind that it is three-dimensional, that the stars are not points stuck to the dome or to a celestial sphere but free-floating lights–no, impossibly distant suns–hanging unsupported in…nothing. In space, or in spacetime, which is harder to think about but amounts to the same thing.

One thing that I find helps me in trying to escape the tyranny of the spherical sky is to imagine that I am looking not up, but out, or even down. It works best if I lie down with my feet pointing south, and imagine that I am hanging off the side of the Earth like a picture on a wall. I used to do this in the front yard of my parents’ house, under radically dark rural Oklahoma skies, and to enhance the illusion I would dig my fingers into the dirt to keep from sliding off. When I tried it Saturday night I managed a mental 180: for a few minutes I fooled myself into thinking that I was hanging facedown, with the whole Earth above me like a great balloon tied to my back, staring down, down, down. Down forever into a great cosmic gulf in which the stars and clusters and galaxies were distributed at different depths, unevenly, like coral reef fish seen by someone snorkling at the surface. I wanted to let go, cut the balloon string, and fall into those distant deeps.

Eventually I came back down–or was it back up?–went back to the telescope, and got back to work. But the aftereffects of my perceptual voyage into deep space–really deep, fall-into deep–lasted like a slight electrical charge, a pleasant tingling in the brain.

The next time you’re outside under dark skies, try it and see where you go.

Morning panorama from the east end of the airstrip–click to enlarge

I pushed through to about 4:30 and then crawled in the back of the Mazda for a few hours’ rack. By about 8:30 it was too bright and hot to sleep anymore so I got up, got some badly-needed caffeine on board, and went about the day’s business. Which on the morning after a stargazing run with London means a hike.

A nice lineup of TeleVue refractors. From left to right, I think they are a TV-101, TV-85, TV-76, and TV-60. With mounts, this is probably $10,000 worth of equipment. Photo by Terry Nakazono.

On our way through camp we got to peer at other peoples’ scopes, in the manner of nosy neighbors. This lineup of TeleVue refractors was certainly droolworthy.

Of the many cool scopes we saw, my favorite was this homemade motorized binocular chair. The twin 6″ reflecting telescopes feed light to the eyepieces. The scopes can raise and lower as the observer raises and lowers his head, and the whole chair turns and reclines at the observer’s command thanks to a hand-held control paddle. Given my love of binocular astronomy, something like this might be my ultimate observing setup.

We didn’t have as much time for our hike as we did in 2010. Then we walked about five miles all told, over about three and a half hours. This time we had about an hour and a half, but we still managed to cover a lot of ground and see lots of cool stuff.

We used saguaro cacti as waypoints. This one seemed to be telling me something…

Back from a successful “bone hike”. Photo by Terry Nakazono.

At the 2010 ASP London was about a week shy of his 6th birthday. When we started out on that hike, he announced that it was going to be a “bone hike”. I didn’t have the heart to tell him that you can’t just decide to walk out into the desert and have any guarantee of finding bones. I figured we’d get what we’d get, and I’d break the tough news later if it became necessary. As luck would have it, it wasn’t–one of our first finds, just a few hundred yards from camp, was a big fragment of a cow tibia.

This time London knew going out that we’d probably get skunked, and it certainly looked like we would for most of the hike. But on our way back, within a stone’s throw of the closest RV, we started seeing the clean bright white of sun-bleached bone. We picked up a shoulder blade and parts of three vertebrae, perhaps from the same cow that lent us its tibia two years ago. We left behind a couple of ribs and another shattered vertebra for the next people to pass that way hunting for bones–possibly our future selves, if nothing turns up sooner on our next AASP morning-after bone hike.

I’ll end this post like I ended the last AASP observing report, with a photo of Darrell and London and myself, standing on a dusty abandoned airstrip in the exact middle of nowhere–a seemingly unremarkable spot that has become one of my favorite places on Earth. I’m already looking forward to my next Arizona star party. I hope I don’t have to wait two years to get back.


Hey, nice sketch!

October 16, 2012

Just a quick hit: Justin Balderrama, a fellow PVAA member who blogs at The Young Astronomer, had one of his sketches chosen for the Astronomy Sketch of the Day this past Sunday. Congratulations, Justin!


Observing Report: My fifth anniversary at the eyepiece

October 9, 2012

Moonrise on Mount Baldy, Oct. 3. Photo by Agnes Kwon.

Last Wednesday evening was the fifth anniversary of my first light with my first telescope. On Oct. 3, 2007, the UPS guy dropped of a big box with an Orion XT6 inside. I built the scope on the living room rug, used a distant water tower to get the finder aligned, and waited impatiently for nightfall. The first object I pointed the scope at was Jupiter. I’d already seen Jupiter and all four Galilean moons with binoculars, but the view in the telescope was indescribably better. I could see cloud belts and colors and details I would not have thought possible. After Jupiter I turned the scope to the Andromeda galaxy and let my eyes collect photons that had been travelling for 2 million years. My final object for the night was the Pleiades, which just barely fit in the field of view of my low-power eyepiece.

One thing I have always been glad of is that I started keeping an observing log from the get-go. It’s an Excel file with date, time, location, instrument(s), objects observed, and notes from every binocular or telescopic observing run since that first one. It runs to 2297 rows now, with notes on all 396 of my observing sessions to date. I was kind of hoping that my fifth anniversary in amateur astronomy would coincide with my 400th observing session, but I’m not quite there yet.

It’s a fitting time to reflect on all of the amazing things I’ve seen in the past five years–and to ponder all of the wonders I have yet to see.

Waning gibbous moon, photo by Agnes Kwon.

A couple of months ago I made a list of my favorite observations of my observing career so far. Heading the list are the annular eclipse and the Venus transit from earlier this year. Other highlights include seeing the gegenschein at the All-Arizona Star Party in 2010, watching the crescent moon pass in front of the Pleiades from the Salton Sea, and tracking a comet as it moved against the background stars, with fellow PVAA member Steve Sittig up at the Webb Schools (never got around to blogging that one–shame). These were all fantastic things to witness with my own eyes. Each one is engraved indelibly in my memory. Probably the most moving was seeing the little black dot of Venus crossing the face of the sun, and knowing that that tiny dot was a world, and not jut any world, but a twin of Earth. It was a profound–and profoundly odd–experience.

I’ve learned a lot about observing itself in the past five years. I know my way around the sky pretty well. I know that if the night is sufficiently clear and if I’m fanatical about dark-adapting my eyes, I can see the Crab Nebula with 15×70 binoculars from my driveway. After buying and selling lots of telescopes, I’ve learned what telescope I have is way less important than how I use it–and mainly, just that I use it.

And most importantly, I’ve learned that I am a social stargazer. If there is a common thread that ties together all of my favorite observations, it’s that they were shared with others–sometimes a whole crowd of people at a public outreach, and sometimes just one or two friends in the dead of night in the middle of nowhere. Oh, I’ve spent plenty of nights at the telescope alone, and those solo vigils are often how I get away from it all. But the “Aha!” moment of discovery is reduced to a dim shadow if there’s no-one there to share the “Aha!” with.

iPhone photo by Chad Claus, shooting afocally through my Orion XT10 with a 32mm Plossl eyepiece.

So it’s fitting that last Wednesday night I went up Mount Baldy with a group of friends and spent the evening stargazing. Most of them are new to observing so I gave them a quick tour of some late summer and early autumn highlights. I didn’t see any objects I hadn’t seen before, but it would be a mistake to say that I didn’t see anything I hadn’t seen before. The way that the Wild Duck Cluster just resolves into a dense swarm of seemingly tiny stars at 120x, or the Galilean moons of Jupiter stacked in an almost perfectly vertical line just above the horizon, are sights that I will not soon forget. And even overly familiar objects take on new life when you see them for the first time through the eyes of another–something I first learned as a parent, and am learning again as a stargazer.

As I look to my next five years as an amateur astronomer, I am thinking about what’s next. And that means not just whether or not I’ll get a bigger, nicer telescope, or what observing projects I’ll take on during that time–it also means who I’ll share those observations with, and what we’ll see together.

I can’t wait.


Observing Report: a semi-cloudy night at Joshua Tree

October 8, 2012

My scope at Joshua Tree Saturday night. Clockwise around the scope are the bright star Capella just in front, the constellation Perseus (12:00), the Pleiades (2:00), the Hyades (V-shaped arrow of stars directly oppose Capella), and Jupiter (4:00). Photo by Kevin Zhao.

Saturday evening I was at Joshua Tree. My summer anatomy students invited London and me along to the Indian Cove campground. I didn’t have room in the car for the big gun so I took my 5” Mak, which is what it’s for—times when I need a decent amount of aperture in a small package. That was no loss: the sky was striped with high, thin clouds all night and never really cleared out. We got decent views of a few things, but the 10” would have been wasted. We used the Mak to look at the Double Cluster and Jupiter. In moments of steady seeing there were quite a few cloud belts showing, and all four Galilean moons were lined up on one side of the planet, which was pretty cool. London brought along his AstroScan and we used it to look at extended objects like the Pleiades and the Andromeda galaxy.

iPhone panorama by Chad Claus. Click for the big version!

The clouds might have made for lousy telescopic views but they made for gorgeous naked-eye skywatching. At sunset the whole sky was striped with light from one horizon to the other.

Here’s another view, actually taken by me for a change. This is the unprocessed raw image, direct from my Coolpix 4500.

Moon halo photo by Kevin Zhao. Jupiter is inside the ring at 1:00, and the Pleiades are outside at about the same angle.

When the moon rose around 11:30, it was surrounded by a ring of faint light. I thought it was a moonbow, but that’s something different. The ring we saw around the moon is called a 22-degree halo and apparently has no other or more poetic name. That’s a shame. In the early morning, when the moon had gotten well above the horizon, it was surrounded by a complete circular halo with radiating clouds on either side. That was worth the clouds. I’ve been under wonderfully clear desert skies many times, but I’ve never seen a moon halo quite like that. For once, I think the clouds were worth it.

Update: There wasn’t just a moon halo, there was also a sun halo Saturday afternoon. Agnes Kwon captured it in pixels. Witness:

Many thanks to Agnes, Chad, and Kevin for letting me illustrate my post with their awesome photos!


Observing Report: SkyScanning in Oregon

October 2, 2012

I was up in Oregon last week to visit my university’s second campus in Lebanon. It was a kill-many-birds-with-one-stone type trip: in addition to day-job work in Lebanon on the weekdays, I got in a productive meeting about a joint project with a paleontological colleague who lives nearby, and–the point of this post–last Wednesday night I got to go stargazing with frequent commenter Doug Rennie.

Doug lives up by Portland and I was staying in Albany, so we needed someplace in between with reasonably dark skies. We settled on Baskett Slough Wildlife Refuge, just north of Dallas, OR. We met in Dallas for dinner and then drove out to the slough.

I had along a new-ish pair of Nikon Action 10×50 binoculars that I picked up this summer and haven’t used much. Doug brought his Celestron SkyMaster 15x70s–the same model I have and love–and his Orion SkyScanner 100 tabletop telescope.

Neither of us really knew what to expect in terms of sky quality. The waxing gibbous moon was only three days shy of full, and I was seriously concerned that we’d get “mooned out” and not be able to observe anything in the deep sky.

This brings up the interesting question of how much moonlight it takes to significantly degrade the night sky. I’ll write a full post about it someday, but for now it is enough to note that the brightness of the moon increases exponentially on the run up to opposition (full moon), and decreases exponentially after full moon. For explanations of why that is, check out this graph and this tutorial and read up on opposition surge and heiligenschein. The upshot is that three days shy of full the moon is only perhaps a quarter as bright as it is at full moon, and happily we were able to see quite a bit.

I didn’t know that when we started out, though, but I knew that we wouldn’t see anything if we didn’t try. Ursa Major was opposite the moon, getting closer to the horizon, and with it some of the best and brightest galaxies in the sky. I spent a few minutes faffing around and managed to get M81 in the field of view. It was dim, but it was there, and our observing run was underway.

Some hazy clouds were skirting the northern horizon, and I was worried they might come south and ruin things for us. Also, after the frustrating chase and unimpressive view of M81 we needed a win, so our next target was the Double Cluster, NGC 869 and 884. They were spectacular–two brilliant knots of stars in the rich Milky Way starfields of northern Perseus.

After that we hit some other summer and fall “best of” objects, including the Andromeda galaxy (M31), the Great Glob in Hercules (M13), the Ring Nebula (M57), and the Dumbbell Nebula (M27). Next to M31 we caught the brighter and more compact of its two Messier satellite galaxies, M32. I don’t know if M110 would have been visible or not. It’s a tougher catch, especially under less-than-perfect skies, and I didn’t waste any time looking for it.

M13 was an easy catch, and we kept running up the magnification to see if we could get it to resolve at all. Doug’s 6mm Expanse yielded 67x and, we thought, some tantalizing hints of detail. We Barlowed it up to 133x and the cluster took on the slightly grainy texture that is often the most resolution one can get in a small scope. We also tried lots of magnifications on the two planetary nebula, M57 and M27. We could only glimpse in averted vision the slightly darker center that makes the Ring a ring, and the Dumbbell showed the barest hint of its bilobed structure.

After that we turned back north and plied the starry Milky Way between Cassiopeia and Perseus. Cassiopeia is just lousy with asterisms and open clusters; the only ones we bothered to identify were M103 and nearby NGC 663, which is bigger and brighter.

A highlight of the evening was sweeping the Alpha Persei Association with binoculars. It’s really seen best this way–very few telescopes have a wide enough field of  view to show more than a small part of it. I once read a description of this big, close cluster–variously catalogued as Melotte 20 and Collinder 39–as a “vast wonderland of far-flung suns”, and I can’t look at it without those words coming to mind.

Since Perseus was now a good way up the sky I thought it would be worthwhile to track down the open cluster M34. I’m glad we did. When Doug looked at it he said, “I know this cluster–I’ve drawn it!” And he had–his sketchbook recorded the fingerprint-specific arrangement of stars that make up the cluster. I was most impressed by this–by the drawing and his visual memory both.

At this point we were winding down a bit and just scanning around with binos, taking things as they came. Halfway down the western sky I found the brilliant blue-white double star 16/17 Draconis. By this point Doug’s green laser pointer was fading a bit from cold and overuse, but with some yammering and gesticulating on my part–and much patience and good humor on his–we were able to get both pair of binos on target. That really is a gorgeous double, and just wide enough to be clearly split in low-power binoculars. I recommend it.

Our last stop of the night was the Pleiades, which had just climbed over the northeastern horizon. They were stunning, as always. That gave us a total of nine Messier objects, three non-Messier NGCs (663, 869, and 884), another big open cluster (the Alpha Persei Cluster), and a double star. So, 14 objects in all, which is pretty good for a two-hour session under any conditions.

Using the SkyScanner was a revelation. I had taken a few brief peeks through Terry Nakazono’s SkyScanner on our Baldy runs, and been impressed, but I’d never gotten to just pick one up and freewheel. And “freewheel” is a pretty good description of what we were doing. The scope is light enough that you don’t think twice about just picking up one-handed and moving it wherever you need it. At the same time, four inches is a lot of aperture, and I was consistently impressed by how much the little scope could do, both in terms of light-grasp and resolution. Doug must have collimated it to within an inch of its life, because the image was still good at 133x–a real achievement in any small, fast Newtonian. Finally, I didn’t notice any issues with the focuser. This is one of my pet peeves. Fast scopes have steep light cones and it takes a precise focuser to consistently hit focus without going past in either direction. One of the things that drove me crazy about the Celestron FirstScope was the lousy focuser, which consistently overshot focus. So when I say the focuser on the SkyScanner didn’t draw attention to itself, that’s a good thing. I’m sure that like all consumer scopes there’s some sample-to-sample variation with the SkyScanner, and Doug’s might be an unusually fine example, but so far both of the SkyScanners I’ve gotten to use have impressed me. I think I’ll get one for the Suburban Messier Project, which is on hold until it cools off some–it was 107 here today. In October!

Oh, and speaking of the Suburban Messier Project, I was most impressed by the quality of Doug’s sketches, and by the fact that, having sketched something once, he could recognize it at the eyepiece later without knowing in advance what it was. I’d like to have that level of familiarity with these objects, and I intend to get it–by sketching them. Stay tuned.