Archive for the ‘Open cluster’ Category

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A planetary observing run on Mount Baldy

August 2, 2018

Last night I went up to Cow Canyon Saddle with some fellow PVAA members and other friends, for an informal star party. Venus, Jupiter, Saturn, and Mars are nicely lined up along the ecliptic right now, so we went to take a look.

I was rolling with London’s XT4.5 dob and my Apex 127 Mak. I hadn’t gotten the Apex out in a little over a year, and it was nice to confirm that it’s still in fighting trim.

Me, not so much. It was my first session with a scope – any scope – out in months, and I was a little scattered. I had to rifle through three bags to find my good diagonal, and it took three attempts to get out of the house with both my phone and my headlamp. The rustiness even extended to the sky. Normally I can get most of the good stuff using memory and dead reckoning, but I had to haul out an atlas to remember how to get to M81/M82 and M11. Sad!

I got up to Cow Canyon Saddle a little after sunset. Amanda and Ron Spencer and their kids were already set up, checking out Jupiter with their 90mm refractor. Ludd Trozpek was there, too, with a 10-inch dob. My friends and WesternU colleagues Thierra Nalley and Jeremiah Scott arrived a few minutes later.

Thierra, Jeremiah, and I started in Venus, which is in a half-full phase right now. We quickly moved on to Jupiter and then Saturn. Mars hadn’t cleared the mountains to the east so we spent some time running up the magnification on Saturn. The seeing was phenomenal. We put the 8.8mm ES82 in the Apex 127 for 175x and Saturn looked like it was nailed to the wall. We put in the 5mm Meade 100-degree and at 308x the seeing was visible, not as the usual small-scale shimmers, but as an occasional wave of distortion washing over the whole field of view, as if we were viewing Saturn through a thin film of water with a low ripple now and then. In my experience, nights on which I can push past 300x are few and far between, so we got pretty darned lucky.

Enough about the eyepieces and the conditions. The planets looked unreal. Even at low power, Saturn’s Cassini Division was easy and crisp, as if it had been punched out of the disc of the rings with a metal press. At higher power, the shadow of the rings on the planet and the shadow of the planet on the rings were equally stark. And the planet itself was striped with pastel bands of salmon and cream. We had no problem holding any of these details in direct vision. As always, it was a kick in the brainpan to be reminded that while I’ve been going about my little business on this little planet, Saturn has been doing its own thing out there, 800 million miles away: regal, immanent, undeniable. We caught Rhea and Titan, too, but failed to spot the other moons.

Jupiter was only slightly overshadowed by its smaller sibling. The King of Planets was wrapped in dozens of belts and zones, down to the limit of vision, with the four Galilean moons neatly arrayed to either side.

Of course, we had gone up in large part to look at Mars, and see if we could detect any details through the nearly-global dust storm. When Mars cleared the mountains to the east, it was instantly the brightest thing in the sky. Even Jupiter looked wan compared to the red planet. I think every scope on the mountain was aimed at Mars within the first minute. The seeing may have been good up high, but Mars was fairly boiling in the near-horizon turbulence. Still, we could see the north polar cap immediately.

We decided to let Mars climb up out of the murk, so we switched to the deeper sky for a while. Lyra was almost at the zenith and Epsilon Lyrae was an easy split at 175x in the Apex 127. We spent some time with the Ring Nebula while we were in that neighborhood, then swung north to catch M81 and M82 before they got too low. Then it was back to the band of the Milky Way to pick up M11, the Wild Duck Cluster (after the aforementioned faffing about) and Albireo.

We went back to Mars and the view in clear air was vastly improved. The north polar cap was steady, and we caught fleeting hints of detail elsewhere on the planet. I don’t think that was all imagination – the most recent Hubble images show some of the dark features in the southern hemisphere starting to emerge through the dust. We had fun, both with the observing and with teasing each other about Percival Lowell, canals, and Tharks.

Jeremiah had been keeping an eye on Cassiopeia as it rose in the northwest, and I was casting frequent looks in that direction as well. A little after 10:00 the Double Cluster finally cleared the local horizon and we got a nice look at 48x in the Apex 127 (as low as that scope goes, using the trusty 32mm Plossl). Our final object was the heart asterism around Sadr at the center of Cygnus, which I wrote about for the Binocular Highlight column in the July issue of Sky & Tel.

The Spencers had departed before we looked at the Double Cluster, and Thierra and Jeremiah left after Sadr. Ludd and I finished the session with a few minutes of binocular observing. He had along a recent acquisition: a WWII-vintage Sard 6×42 with a true field of 11.9 degrees. It’s a legendary instrument that lives up to the legend. The first thing you notice when you pick them up is that they’re heavy – there’s a lot of glass in there. That’s in part because the prisms are huge. Unlike some modern binos that skimp on prisms, the Sards have prisms that are if anything maybe a little oversized. The eye lenses are also immense. It’s not just a lot of glass, it’s good glass, as I could tell as soon as I looked through them. It’s not sharp to the edge – stars take on interesting shapes in the outer 25% or so of the field – but it is impressively sharp over a huge true field, with excellent clarity. It was an interesting experience, looking at all of the constellation Lyra at one time. Cassiopeia almost fits – you can see all but one of the stars at either end of the W/3/M. Ludd reports that under darker skies, the Sards are a wonderful tool for scanning the Milky Way. They’ve re-fired my occasional interest in low-power, super-wide-angle binos. If anything comes of that, you’ll hear it here first.

So, all in all a fantastic observing session, with some of the best views of Jupiter and Saturn that I’ve ever had. I should do this more often.

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Observing report: Saturday night stargazing on Mount Baldy

April 2, 2017

Waxing crescent moon, afocal shot by Eric Scott with Samsung Galaxy S6, shooting through Orion XT10 reflecting telescope.

London and I went up Mount Baldy last night with our friends Thierra Nalley and Eric Scott. Marco Irigoyen and Leandra Estrada joined us up on the mountain. We went up to look for comet 41P, but that didn’t pan out.

Since we went ostensibly to look for the comet, I brought the XT10 for firepower, and lots of binoculars. We got set up at Cow Canyon Saddle at about 8:30. Our first target was Orion, before it could sink into the light dome over LA. Second targets were the Pleiades and the Double Cluster. The Double Cluster in particular looked magnificent. I’ve been on a small-scope kick for a while so the XT10 hasn’t been out much, and I tend to forget what a potent instrument it is, especially under dark or semi-dark skies.

The skies on Mount Baldy last night were definitely semi-dark. Even three days shy of first quarter, the waxing crescent moon was bright enough to throw shadows and rather seriously degrade the darkness of the sky.

I tried for the comet but just couldn’t see it. I had the chart, knew where to look, and swept the area repeatedly with binoculars of all sizes and with the XT10, and I got bupkiss. This was after catching the comet easily in 7×50 binos every time I looked for it in Texas last weekend – but I wasn’t fighting any moon then. I think the comet is so big and diffuse that the surface brightness is low, and therefore it is easily swamped by moonlight. It certainly was not evident last night.

While we were in the neighborhood of the Big Dipper, we had a look at Mizar and Alcor, the famous double star in the dipper’s handle. Then for comparison we checked on Sigma Orionis, and then Marco wanted a look at Jupiter. After Jupiter we went on an extended tour of the deep sky, in which we observed:

  • M81, M82 (interacting galaxy pair)
  • M97, M108 (planetary nebula and galaxy in same field)
  • M3 (globular star cluster)
  • M37 (open star cluster)
  • M35 (open star cluster)
  • M104 (Sombrero galaxy)

In addition, we also saw three more open star clusters with our naked eyes and/or binoculars: the Hyades, M44, and the Coma Berenices star cluster.

We finished up on the moon, and then Jupiter again. We spent quite a bit of time getting pictures of both with Thierra’s and Eric’s phones. By coincidence, they both have the Samsung Galaxy S6, which has a very full-featured slate of camera options. Leandra is a pretty talented photographer and she was able to coach us on what settings to use. I think the results are pretty astounding, for handheld shots using phones. Here are the two best images of Jupiter, captured by me using Thierra’s phone and Leandra’s advice:

Here’s a composite of Jupiter and the Galilean moons – the planet was overexposed in the original to get the moons to show up, so I replaced it with the better of the two shots above.

And here’s a comparison screenshot from Sky Safari Pro 5 identifying the moons – from left to right in the above image they are Callisto, Europa, Io, and Ganymede.

As usual, the view at the eyepiece was about an order of magnitude more detailed than what the photos captured. One thing that I had never seen before with one of my own scopes was a band of ruffled white clouds within the north and south equatorial belts (the prominent orange-brown stripes on either side of the equator). The barest hint of this survives in the photos. It was a pretty mesmerizing view. For eyepieces we used a 32mm Plossl (37.5x), 28mm RKE (43x), 24mm ES68 (50x), 14mm ES82 (86x), 8.8mm ES82 (136x), and 5mm Meade MWA (240x). The most used were the 28mm RKE, 14mm ES82, and 5mm MWA. If you’re wondering why we used both a 32mm Plossl and a 24mm ES68 – since they give the same true field of view – we used the Plossl during the afocal photography because it gives a wider exit pupil, which is easier to keep the camera’s aperture centered inside.

Even though we missed the comet, I was pretty happy with what we did see – at least one of every major class of deep-sky object, including all of the stages of the life cycle of stars. In the disk of the Milky Way, new stars are born from vast nebulae of gas and dust, like Orion. In time, heat and light from the newborn stars push away the remnants of their birth clouds, leaving behind only the stars themselves, as open star clusters (‘open’ as opposed to globular). Over time, the stars in open clusters drift apart to become ‘field stars’ like the Sun, no longer gravitationally bound to their siblings. When the run out of fuel, stars blow themselves apart in supernovae if they are 8 times the mass of the Sun or larger, whereas smaller stars blow off their outer layers of gas to form planetary nebulae like M97. Whether stars die suddenly in supernovae or slowly as planetary nebulae, the matter blown out by dying stars enriches the galactic gas and dust clouds, and in time it will be incorporated into new generations of stars and planets. We are products of this process – all of the elements in our bodies other than hydrogen were born by fusion in the hearts of stars, and seeded into the galaxy’s spiral arms when those stars died.

Farther out, globular clusters like M3 orbit the core of the galaxy on long elliptical orbits that are not flat, but come looping in from all directions. The stars in globular clusters are typically very old, 12 billion years or more. We know very little about how and why globular clusters formed, and how they came to have such weird orbits. Probably they are some kind of developmental leftover from the formation of the earliest galaxies in the first billion years after the Big Bang – astrophysical fossils, if only we knew how to interpret them.

All of these processes are going on in other galaxies as well, especially spiral galaxies like M81, M104, and M108.

To put all of that into context, here are all of the objects we observed again, this time ranked from closest to farthest:

In our solar system:

  • moon – 240,000 miles or 1.3 light seconds
  • Jupiter – 370 million miles or 33 light minutes (currently – Jupiter is about 5 AU out from the sun, but right now we’re on the same side of the sun so it’s only 4 AU from us)

In our spiral arm of the Milky Way galaxy (the Orion spur):

  • Mizar and Alcor (double star) – 83 light years
  • Hyades (open star cluster) – 151 light years
  • Coma Berenices cluster (open star cluster) – 280 light years
  • M45 (Pleiades; open star cluster) – 440 light years
  • M44 (Beehive; open star cluster) – 577 light years
  • Sigma Orionis (multiple star) – 1255 light years
  • M42, M43 (Orion nebula; star-forming region) – 1344 light years
  • M97 (planetary nebula in same field as M108) – 2030 light years
  • M35 (open star cluster) – 2800 light years

In the next spiral arm out from the galactic center (Perseus arm):

  • M37 (open star cluster) – 4500 light years
  • NGC 869/884 (Double Cluster; open star clusters) – 7500 light years

In the galactic halo of the Milky Way:

  • M3 (globular star cluster) – 34,000 light years

External galaxies:

  • M81, M82 (interacting galaxy pair) – 11 million light years
  • M104 (Sombrero galaxy) – 31 million light years
  • M108 (galaxy in same field as M97) – 46 million light years

That is very satisfying to me, to take in such a menagerie of celestial objects, at so many scales and distances, in the space of a couple of hours armed only with a comparatively inexpensive telescope and an idea of what’s out there to be seen. I can’t wait for next time.

Saturday night astro crew. Left to right: Marco Irigoyen, Leandra Estrada, London Wedel, Matt Wedel, Thierra Nalley, Eric Scott. Photo courtesy of Eric Scott.

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My article in the March 2017 Sky & Telescope

January 27, 2017

jan-2017-st-cover-wedel-article-highlighted

This is one was an easy write-up, because it had been in my head and in my notebook for a long time. Way back when I first got tapped to write for S&T, I pitched a tour of the winter Milky Way from Puppis to Gemini. I’d never written for a magazine before and I had no idea how much sky it would take to fill 1600 words. Turns out, all I got through on the first attempt was Canis Major, Puppis, and a couple of odds and ends like M48. That was my article in the December 2015 issue.

Right after that came out, I pitched the unfinished second half, and now it’s out. Like that first article, it’s a tour of the winter Milky Way pitched at binocular users, but hopefully useful for telescopic observers, too. This piece runs from Monoceros through northeastern Orion to southern Gemini. The March issue of Sky & Tel is probably hitting newsstands this week. If you get a copy, I hope you enjoy the article.

If you’re thinking that Gemini is a pretty arbitrary place to stop cruising the Milky Way, you’re not wrong. I can say no more for now, but stay tuned…

Update: whoops, I originally put January in the post title instead of March! This is, of course, the March issue, it just came out in January. Sheesh.

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Sunday night on Mount Baldy

November 3, 2015

Moon through trees 2015-11-01

Sunday night I went up Mount Baldy for a solo session. I was rolling with the C80ED, which has become my default grab-n-go rig.

One of my goals was to test a couple of new eyepieces. Several astro retailers had a big sale on Meade wide-angle eyepieces last month. I was torn between the 20mm and the 5mm Series 5000 Mega-Wide 100-degree EPs (man, is that a mouthful or what?). The 20mm would have been a great low-power, widefield scanner, which is something I’ve gotten progressively more interested in this fall. But for a long time I had been without an EP shorter than my 6mm Expanse, which is not without its problems, so I sprung for the 5mm instead.

In the meantime, thanks to this thread on Cloudy Nights I had become aware of the VITE eyepieces. These odd little birds come in only 3 focal lengths (at least so far): 23mm, 10mm, and 4mm. They are three-element EPs with one aspheric plastic element and plastic bodies. They’re about $17 apiece on Amazon, or $9 apiece on eBay. I ventured my nine bucks and got the 4mm from eBay, thinking it would make an interesting comparison with the 5mm Meade 100-degree. I had done a quick comparo late Saturday night from my driveway on the moon and the Orion Nebula – more about that in a bit.

Sunday evening on mount Baldy I cruised through the highlights in Lyra, Cygnus, and Sagitta. I did a quick, rough sketch in my notebook of the open cluster NGC 6823. It has a curl of stars wrapping up around it like a fiddlehead fern.

NGC 6823 sketch

After that a couple of high school kids and their little brother drove up nearby, and I spent about an hour showing them around the sky – the Dumbbell Nebula (M27), the Double Cluster, Pleiades, Andromeda galaxy, Polaris, M15, 61 Cygni (aka Piazzi’s Flying Star), and finally the Messier open clusters in Auriga – M37, M36, and M38.

The kids left about 10:30. Since I was in the area I had a look at M1, and then cruised down to Orion. The constellation was slowly crawling over the ridgeline to the east, so I started visiting the bright stars, and in some cases splitting them. First up was Meissa, which was elongated at 68x and cleanly split at 120x in the 5mm MWA and 150x in the 4mm VITE.

Mintaka was an easy wide split at only 25x. Seeing was not good, but Eta Orionis appeared to be elongated east-west at 120x and 150x. The view in the VITE was kind of a mess, so I spent a few minutes just cruising around Orion’s belt and sword with the 5mm MWA. Alnitak and its dim companion were widely split. I turned south to Sigma Orionis. I’ll have to check my notes, but I don’t believe I’d ever split this star before. It’s pretty great, with a group of three fairly bright stars and a second group of three much dimmer ones. I backed down to 68x and all six stars were still nicely split, and frankly looked a bit sharper, although that might have been down to bad seeing.

Sigma Orionis sketch

So, here are my thoughts and observations on the 6mm Expanse, 5mm MWA, and 4mm VITE. These don’t count as an actual review, as I didn’t have equivalent focal lengths to compare, and I’ve only spent a couple of nights with the two newer eyepieces, observing only a handful of objects. Still, I tried them on a variety of things – the moon, globular and open clusters, the Orion Nebula, double stars – and the strengths and weaknesses were consistent. All of these observations are with the C80ED, so the chromatic aberration (CA) with certain EPs is particularly interesting.

6mm Expanse – Has a small but noticeable amount of CA on bright stars. Eye placement is a bit tricky – I get some kidney-bean and full-aperture blackouts until I get my eye placed just so. Comfortable enough once I get my eye in the zone, though. Halos on some bright objects.

5mm MWA – Sharp from edge to edge. No detectable CA, but the edge of the field does look blue until I get my eye centered. No detectable field curvature. Eye relief is pretty tight – when I move in close enough to see the entire field, my eyelashes brush the lens about half the time (I do have long lashes, but still). I have to move my head around to focus on objects in different parts of the field. Very immersive – I feel like I could climb through the eye lens and into space. The rubber eyecup is annoyingly loose – it frequently comes off with the dust cap.

4mm VITE – Can’t focus the whole field at once. Center of the field is sharp enough, but objects start getting blurry halfway to the edge of the field and are entirely defocused at the edges. ‘Sweet spot’ is pretty small. Considerable CA – makes an ED refractor perform like a short fast achromat! Strong internal reflections from bright objects on the edge of the field, or just out of the field. Almost impossible to focus on the lunar terminator if it’s centered – a big bright glow from the lit side of the moon fills the center of the field. Eye relief is tight – eyelashes scrape most of the time.

Verdict – The 5mm MWA is a keeper. The eye relief is short but tolerable, and totally worth it for the huge, flat, well-corrected field. As for the VITE, I’m glad I didn’t spend more than $9. I’ve read that these perform better in longer focal ratio instruments, but at f/7.5, the C80ED isn’t exactly fast. So how long does the light cone have to be for the VITE to perform well – f/10? f/15? At those focal ratios, it would take an exceptionally still night for a 4mm EP to be useful. I will try the thing in my Mak and probably in my C102 but I am not expecting much. People on CN seem pretty happy with the 23mm, so maybe there’s some variation within the line.

Back to the observing report. By midnight I was tired and my feet were cold. I had just resolved to pack up and head home when I saw that the hillside behind me was lit up by moonlight. The moon was coming up behind the ridgeline to the east. It had been a long time since I’d had a chance to shoot the moon rising behind trees, so I quickly set up the camera adapter and got to work. My best still shot is at the top of this post. And here’s a video:

I went for the sideways aspect ratio this time, but I didn’t quite get the camera square on to the view. Guess I’ll just have to try again next month.

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My article in the December Sky & Telescope

October 31, 2015
SnT Dec 2015 cover - marked up

Einstein has my article on his mind!

Here’s the exciting news I teased back in September: the December 2015 issue of Sky & Telescope, which is available online and should be hitting newsstands about now, has an observing article by yours truly. It’s a binocular tour of the southern stretch of the winter Milky Way, from Canis Major through Puppis to end in Hydra.

SnT Dec 2015 contents - marked up

The road that led here started back in December, 2014, when I got a very nice email from S. Johnson-Roehr, “JR”, the observing editor for Sky & Tel. JR had stumbled across this very site (possibly because I’d just recommended the newly-reprinted Caldwell Objects?) and asked if I’d be interested in contributing an observing article. We batted some ideas back and forth and quickly settled on the winter Milky Way. I had been through this area of the sky before but I wanted to give it one more pass, both to flesh out my notes and to road-test the star hops I had in mind. I made those observations this spring, wrote the article over the summer, and now it’s out in the world.

I have one favor to beg of anyone who reads the article – I need feedback. This is my first time writing about astronomy anywhere but a blog, forum post, or club newsletter, and I’d like to know (1) what worked, (2) what didn’t, and (3) what you’d like to see in the future. The comment field is open.

There’s a lot more to like in this issue of S&T, some of which will be of particular interest to regular readers of this blog. Tony Flanders has another inexpensive telescope shoot-out. Back in 2011 he and Joshua Roth looked at $100 scopes, in particular the Orion SpaceProbe 3, GoScope 80, and SkyScanner 100 (that article is a free download here, and a follow-up comparing the SkyScanner to the StarBlast is here). This time Tony considers three scopes in the $200 range: the Meade Infinity 90mm refractor and alt-az mount, the Orion StarBlast 4.5, and the Astronomers Without Borders OneSky. I won’t give away any spoilers, except to note that he finds all three to be capable scopes, which I’m sure is no surprise around here.

Another nice review in this issue is Alan MacRobert’s look at the first two volumes of Jeff Kanipe’s and Dennis Webb’s Annals of the Deep Sky, from Willmann Bell. As a deep-sky junkie who likes to read himself to sleep with Burnham’s Celestial Handbook and Stephen James O’Meara, I have been curious about these new books, but I hadn’t heard anything about their quality before reading MacRobert’s article. Sounds like I need to make space on my Christmas list.

There’s loads more interesting stuff in this issue – cover articles on Einstein and gravitational waves, great observing articles by Alan MacRobert, Fred Schaaf, Gary Seronik, and Charles A. Wood, a very nice piece by Sue French looking at some neglected open clusters and double stars in Cassiopeia (an area I thought I knew well)…you get the picture. If you’re not a subscriber, you can find the December issue of Sky & Telescope on your local newsstand, or order a print or digital copy online here.

If you’re new here, welcome! Have a look around, and feel free to comment.

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Double stars and the Double Cluster: a short observing run in bright skies

October 17, 2015

I completed a major lecture Thursday so I treated myself a short stargazing run in the driveway that evening. Transparency was rotten – it was so humid here that even with the temps in the low 70s I was still sweating, and with all that water vapor to bounce back the city lights, the sky was bright to about 45 degrees above the horizon. I did a quick turn around the sky with my old 7×35 binoculars, which I’d not used in ages, and all I could see were the major constellation outline stars. I decided to see what the C80ED could do, in part because it’s my best grab-n-go scope and I knew it would be a short run, and in part since I’d just had it out under much darker skies.

I started on M57, the Ring Nebula, which is obvious even at low power under most conditions. This time out, the Ring was just a ghostly blob in averted vision at any magnification, even when Lyra was still quite high. But the seeing was rock-steady. Epsilon Lyrae, the famous double-double star in Lyra, was very elongated, like a pair of 8s, at 68x, and cleanly split – juuuuust barely – at 100x, although I had to go up 136x to easily hold the split in direct vision. After that I bopped over to Cassiopeia/Perseus to split some doubles (Eta Cass was nice) and look at the Double Cluster. Didn’t attempt a sketch, I was just rolling for aesthetic appreciation, but I did use a lot of magnification and spent more time on the clusters than I usually do. I had not noticed before that NGC 884 has an empty center. I mean, under dark skies there are plenty of stars in the middle, but the bright stars form a series of arcs around the edge, and under so-so skies those outer bounding arcs of stars are all you can see. NGC 869 is the opposite, it just gets more and more concentrated toward the center, albeit unevenly.

Double Cluster from SEDS

The Double Cluster: NGC 884 (left) and 869 (right). Photo borrowed from SEDS.

At 11:20 the clouds suddenly thickened up – in the space of five minutes I went from pleasant observing to totally socked in. After I got everything stowed, I went inside and looked up Stephen O’Meara’s entry on the Double Cluster in his Caldwell Objects book. His observations were gratifyingly similar to mine, but I learned some interesting stuff about the clusters. They are BIG and they are distant: 7300 light years, compared to less than 4000 light years for most Messier open clusters, and dimmed by about 1.5 magnitudes by intervening dust clouds. One shudders to think about how much more impressive they’d be if they were only half as far off and not obscured by interstellar dust.

Anyway, a good run. We’re clouded out this weekend, so I’m glad I got it in.

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Guest post: Whys and hows of astronomical sketching, by Doug Rennie

October 11, 2015

Doug Rennie first opened my eyes to the value of sketching for the visual observer. I’m very happy to host his thoughts on the subject – and his sketch of the Alpha Persei association.

Rennie Alpha Persei association - curved and inverted

Sometime in the late-1990s, I wrote an essay on bibliophila, the love of books, for a literary journal. Thinking back, I recall two quotes I cited in that essay, one from an anonymous French book collector in 1851, the second from renowned literary critic Edmund Wilson – and both relate to the reasons why several years ago I made sketching a regular component of my observing routine.

“Owning a book puts it in your possession,” the Frenchman wrote. “But only reading a book makes it yours.”

For me, the same principle applies to stargazing. Locating and observing a celestial object, be it Messier, NGC, IC, asterism, whatever, produces a visual experience – and another box checked on your Objects Seen list. You now “own” it. Then, too often, you move onto the next one in the catalog, and just as quickly, the one after that. And so on. The impressions and mental images of the object you just minutes ago observed are already dim and vanishing fast in your memory’s rear view mirror.

But.

Not so if you regularly sketch what you observe. Because now you have to slow down, actually study what you see in the FOV, look at it through various eyepieces, seeing it both up close and large and bold – its own entity – and smaller and more subdued and part of a larger celestial context, the latter being what I personally prefer.

Then you put pencil to paper and sketch it.

One star dot at a time. Or perhaps you sketch it twice: Once at high magnification to capture all the detail and maximum star count, a second time pulled back to see both object and surrounding star field, the total celestial tapestry. By the time your sketch is done, you will have spent a half hour, sometimes more, in the company of this one single object. Moreover, you will have a permanent and personal hard copy of what you observed.

In the spirit of that anonymous Frenchman, you will have made the object yours.

The second quote, from Edmund Wilson, is this:

“No two persons read the same book.”

Think about it.

And this, too: Astronomical sketching is exactly the same. No two observers see the same exact object. If you want confirmation, hit a sketching site such as Deep Sky Archive and go to any object, say NGC 6633, and you will see a dozen sketches, often more, by different observers – and no two even look REMOTELY alike. I mean, you would think you were looking at sketches of 12 different objects. Sue French turned me onto this site over a year ago and I thought, Wow this will be great as I would now have a sense of what pattern(s) to look for in future first time searches. Nope.

If anything, more confusing (So, is This what it looks like? Or is it this one? Or . . . maybe . . . this? . . .)

Just as no two persons read the same book, it seems that no two observers see the same object. Even something as “clear cut” an image as, say, the Pleiades will have as many variations as there are observers/sketchers. So one more reason to make every object yours by laying out on paper the testimony of your visual senses for each object you observe on THAT night in THOSE skies with THAT instrument with THAT/THOSE eyepieces.

Now I’ve been observing for just over 3 years, and my background is all humanities, my hard science expertise zero. Or close to it. I am primarily an aesthetic observer who just enjoys drinking in all the beauty up there and, sad to say, pays scant attention to RA and Dec #s, Bortle Scale assessments of my sky that night, recording AFOV and TFOV, etc. I just go out and hunt down what I want to observe, and once I have what I’m after in the EP, I hang around it for a while. Most of the time, but not always, doing a sketch.

I began to sketch almost as soon as I started observing, and my early sketches are, well, “pitiful” would actually be kind. I was going to include one here to illustrate, but in the end could not bring myself to post one. Bad. These things are terrible. Third graders would laugh.

So here’s how I now go about it, and produce some decent-to-me results.

I have an artist’s sketchbook, spiral bound so it lies flat when opened, 8 x 10 inches, hard black cover. Cost under $10. My wife is an artist, so I initially used her drawing pencils, but quickly bought a set of my own at a local artist supply store: 2B, 4B, 6B, 8B, etc. Cheap. I store them in a plastic travel toothbrush case. I also use her recommended eraser, some artists’ gray plastic eraser, “Prismacolo” thing and it works superbly.

I have a scraggly small lined notebook that I use at the telescope and record in it a very rough first draft, focusing on accurate positions and spatial relationships among the stars, and taking care to use different size “dots” for individual stars commensurate with their brightness/dimness and size. I do a fair amount of erasing to get this draft, which is REALLY ragged, as accurate a reflection as possible of what I see.

I first do the outermost stars in all 4 directions just to make sure that I get the entire image I want in, then sketch in the anchor/biggest/brightest stars to get the main pattern. Once this is done, I work outward from there, one quarter section at a time. Seems to work.

The next day, I transfer the image into my sketchbook, now taking time to create perfectly round dots for every star and, often, using one of those plastic architect’s templates (3 bucks at Office Depot) for the larger stars, insuring that I get perfectly round dots for each. On the smaller stars, this is generally not a problem. See the attached sketch of the Alpha Persei Association. The two largest star sizes were done with the template.

Rennie Alpha Persei association - curved

A soft 2B pencil works best for most stars, but for the really tiny dim ones, of which there are generally quite a few, I go to a 2H or HB harder lead pencil which creates a lighter gray hue. When I have completed the entire sketch, I then take a very soft/dark 6B pencil, freshly sharpened and pointy, to go over the larger and darker stars to set them off, as they are through the eyepiece in “real time”, more dramatically from the background stars.

For open clusters, by far my favorite object to observe, I much prefer the look I get through one of my refractors (Explore Scientific AR102, Stellarvue SV80ED, Orion ST80) vs either of my Dobs, the largest of which is a StarBlast 6. With a Celestron 8-24mm zoom eyepiece in place for the first observation, I can go in and out, seeing the object large and up close with maximum stars, then widest field possible which puts the object at the center and gives it more context, and various degrees of both in between. Once I find the sweet spot, to me the ideal meld of object and context, I can go to one of my fixed focal length eyepieces, often an ES 16mm or Agena flat field 19mm. Some objects, such as the Double Cluster, look best in my ES 24mm/82 afov.

That’s it. Nothing more to see here. And, as you can deduce from the foregoing, sketching is NOT all that difficult. I mean, c’mon, it’s not particle physics. So if you’ve not already included sketching as a regular part of your observing, why not give it a test drive next time out?