Archive for the ‘Moon’ Category

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Observing Report: Total solar eclipse on August 21, 2017

August 28, 2017

My parents, Norma and John (seated), and me with London and Vicki (standing), with the projected eclipse.

Long Range Planning

Since the August, 2017, eclipse first came on my radar, my plan was to see it from somewhere on the Great Plains. I had two reasons for this. One, most of my family lives in Oklahoma, and it would be simpler for them to drive up to the eclipse path than to fly to somewhere more remote. Also, on the plains you can usually see weather coming from a long way out, and fronts move in predictable ways. I figured that if clouds did spring up on eclipse day, I’d have a better chance of driving to get around them on the plains than anywhere else.

Originally I’d been thinking Kansas or Missouri, both of which border Oklahoma and would have made short drives for my relatives. But a closer look at the eclipse map this spring dissuaded me. The eclipse would only barely clip the northeastern corner of Kansas, in the relatively densely populated area around Kansas City. The path of totality painted a broad stripe across Missouri, but mostly along a line connecting Kansas City and St. Louis. I figured that area would get hammered by visitors, and the cloud forecast wasn’t as favorable as it was for points west, either.

Map by Xavier Jubier/Eclipse2017.org

Nebraska, on the other hand, looked pretty good. My maternal grandparents used to live in Imperial, in the southwest corner, and they retired just a few miles down the road to Enders. Imperial would make a convenient rendezvous point, both for any family driving up from Oklahoma, and for me, Vicki, and London flying in from California.

In one sense Imperial was not convenient: it’s a long way from any major airport. Two hundred miles from Denver, and three hundred from Lincoln. But I like long drives in the country (really, I do!), and I was happy to trade some driving at either end of the trip if it would save me traffic in the middle.

I guess now is a good time to mention that I did not want to stay on the path of totality. I figured – correctly, as it turned out – that competition for rooms would be fierce, that at least some places would be gouging visitors, and that traffic would be a problem in at least some areas. Instead, I wanted to stay an hour or two off the path of totality, preferably somewhere out of the way, where crowds would not be a problem, but I’d still have a range of possible observing spots within easy driving range. Again, Imperial was a promising choice, and in early February, I called and reserved rooms for my parents and for Vicki, London, and me at the Balcony House Bed & Breakfast (which was outstanding, by the way – it’s worth going to southwestern Nebraska just to stay there).

By now, plans were firming up. I knew that the fall gross anatomy course at WesternU would be rolling by eclipse time, and Vicki and I would need to arrange things so we’d miss as few days of lab as possible (many thanks to our department chair for the time off!). But we also wanted some time in Imperial to unwind, and to visit places important to our family history. That meant leaving on Saturday, August 19, and coming back on Tuesday, August 22. The Balcony House didn’t have any rooms on Saturday night, and in fact, nobody else in Imperial did, either. So we decided to make Saturday an easy day and only drive as far as Holyoke, Colorado. Holyoke is another old family stomping ground – Grandpa and Grandma had lived there for several years, too, and it’s where my mom grew up.

Sun funnel testing in Claremont

The Sun Funnel Rides Again

Gear! I didn’t settle on exactly what I’d be rolling with until Thursday, August 17, just two days before we were to fly. My old Sun Funnel – veteran of the annular eclipse and Venus transit of 2012 and the partial eclipse of 2014 – was in storage in the garage. There was never really any question but what it would be going along; it’s just too darned useful for showing solar events to even small groups of people. I did have to decide which scope to use with it. We’d sold London’s AstroScan, but my flock of airline-portable scopes had grown in the meantime. Strong contenders included the GalileoScope, Tasco-Vixen 9VR, and SkyScanner 100. I set up and tested the 9VR and the SkyScanner, and I ended up going with the latter scope, for several reasons:

  1. It has the most aperture of any scope I was seriously considering.
  2. It’s at least somewhat collimatable.
  3. With its open design, I wasn’t worried about it overheating.
  4. It balanced the best with the Sun Funnel mounted.

For the flights, I put the SkyScanner in the padded bag that my Apex 127 came in, and packed t-shirts and socks around it. The Sun Funnel I broke down – I put the screen material in a folder between sheets of clean paper, and I stuffed more socks in the funnel itself. I also brought along four pairs of eclipse glasses, a piece of #14 welder’s glass (previously seen here), and 10×42 Bushnell binoculars to look for solar prominences during totality.

London with his grandparents in front of the Balcony House in Imperial, Nebraska

One more piece of gear came to me on the road. Sunday morning we woke up in Holyoke, Colorado, had lunch at The Skillet (which had excellent country cooking), and then popped across the street to the Family Dollar for a few odds and ends. I’d been thinking of making a little sun-finder, like the one David DeLano detailed in this post. My SkyScanner has a DIY wooden bracket that is square to the tube, so I just needed something round that I could use to project a spot of sunlight. I ended up going with a $1 empty condiment bottle, which I already blogged about here. When we rolled into Imperial that afternoon, I unpacked all of the gear and did a test run on the sidewalk in front of the Balcony House. Everything was ready – now we just needed clear skies.

Targeting on the Fly

My initial targets for possible eclipse observing spots were the towns of Tryon and Stapleton, Nebraska, both about a half an hour north of North Platte. I picked up a Nebraska road map and highlighted possible routes from Imperial to either Tryon or Stapleton, going either north to the path of totality and then east, or vice versa. Either town would have required about 2.5 hours of driving on a regular day, and I figured it would be smart to budget for eclipse traffic. The east-then-north route to Stapleton had the following problem: it went through North Platte, and if traffic was apocalyptically bad, we might get stuck on the edge of the path of totality, or even outside of it. The north-then-east route to Tryon would get us close to the centerline first, with fewer opportunities to get stuck off the path.

Ah, but then. A few days out, and the weather apps were predicting partial clouds and possibly even rainfall for west-central Nebraska. Right up until Monday morning, North Platte, Tryon, and Stapleton all looked they might get clouded out. So Sunday the five of us – Mom, Dad, Vicki, London, and me – had a council of war. To the level of detail possible in weather prediction, the area around North Platte looked lousy, but Scottsbluff, in far western Nebraska, was supposed to have sunny skies. Between North Platte and Scottsbluff, the weather looked progressively better to the west, and worse to the east. So we changed things up: instead of turning east to Tryon or Stapleton, we’d stay on Highway 61 north out of Ogallala and shoot up to Hyannis, then turn west on Highway 2 and go as far as we needed to find clear skies. This was basically the Tryon plan with the directions reversed: go straight north to the eclipse path first, then drive east or west along the path to a promising destination.

The Drive Up

I wish I had had the time and opportunity to take pictures during the drive up from Imperial. It was beautiful. We left Imperial right after dawn, and the rising sun turned the fields to gold. Within a few miles, we could see banks of fog lying in the low spots on the landscape. And then a few miles further, the fog was lying everywhere. We started driving through fogbanks that congealed into an unbroken blanket by the time we reached Ogallala. The weather apps were still projecting clear skies to the west and, well, unclear skies to the east, so we kept going.

The fog had cleared by the time we saw our first eclipse-watchers, at the fairgrounds in Arthur. There were hundreds of people in RVs, tents, cars, and trucks, looking worriedly up at a sky that was completely socked in with clouds. We kept going, and saw a few hundred more scattered along the side of the road as we approached the center line. About this point we hit what I can barely bring myself to describe as ‘traffic’. At its worst, we were the 9th and 10th vehicles in a convoy of 13, but the convoy was rolling along at a steady 62 or 63 miles per hour, which was fine and certainly not worth the risk of trying to pass someone on a two-lane road in the Nebraska sandhills. The hills themselves were liberally spangled with wild sunflowers. From a distance, they looked like they’d been dusted with pollen. Everywhere we went the landscape was green.

Alliance

From a purely eclipse-viewing perspective, I would have been happy with any of the towns on Highway 2 west of Hyannis. Sure, they were a few miles off of centerline, but the difference in the duration of totality would have been trivial. And I figured we’d miss the big crowds expected at Alliance. But this plan had one fatal flaw, which I did not anticipate: a complete absence of public restrooms west of Hyannis. If I’d been by myself, I might have just pulled over anywhere and, er, recharged the water table as needed, but that’s a less attractive option to a group that includes two women and two senior citizens. Actually, there may have been a public restroom in Lakeside, but we had no chance to find out, as there was a big train blocking the road into town when we came by. So we headed on into Alliance and braced for the worst.

Our setup at the Western Nebraska Community College shindig. The forest of telephone poles in the background is where line repair people train.

The worst turned out to be not that bad, actually. We drove past a big group assembled on a grassy field on the east edge of town, and on to the first gas station that looked like it might have restrooms. By the time we’d all had a biology break, it was almost time for the eclipse to start. We decided to head back out to the east edge of town and see if the group on the grass still had some parking spots. This turned out to be an excellent choice. The parking was organized by the Western Nebraska Community College, which had free porta-potties and eclipse gear for sale. We ended up next to a family from Denver that we had met in line at the gas station. They all had eclipse glasses but no other optics, so I set up the Sun Funnel so they could watch with us, and they returned the favor by taking pictures of our party.

The Eclipse

As soon as we had the cars parked, I was busy setting up the Sun Funnel, while everyone else got folding chairs set up and got their eclipse glasses on. I got the photo above, my first shot of the eclipse, at 10:45 AM.

There was a wind out of the north that kept threatening to snatch our hats away, and it was flirting with blowing the scope over. I can’t remember ever setting up the Manfrotto tripod for low use, with the legs spread almost straight sideways, but I remembered from the documentation that doing so was possible. That fixed the stability issues with the scope, and from that point on, all we had to do was re-aim it every few minutes (I’d already made this switch in the family shot above – that shot is out of order in terms of eclipse phases). As I mentioned in a previous post, not only was the dollar store mustard bottle sun finder cheap and effective, but I could see the projected dot through the translucent walls of the bottle so I didn’t have to get my head behind or underneath it to aim the scope – handy when the sun was almost directly overhead.

A labeled shot from the end of the eclipse, when all six of the big sunspots were visible, with the Earth added for scale. All of the other crud on the image is dirt and bits of grass – that’s what happens when gear is left out in the wind in a grassy field for three hours.

There were half a dozen nice sunspots, and it was fun to watch the moon overtake them. A lot of the people who stopped by to look at the sun funnel weren’t familiar with sunspots, so I gave them the quick spiel: giant magnetic storms on the sun, with the biggest that we could see then being about the same size as planet Earth.

About halfway between first contact and totality, the north wind started pushing clouds across the sky, which you can see in the above video. This added some definite suspense to the proceedings, especially when, about 5 minutes before the start of totality, a huge “dreadnought class” cloud came over. I think everyone on the field was on pins and needles – we could still see the sun, as the next photo demonstrates, but it wasn’t what you’d call a great view.

Fortunately the cloud moved out of the way right at the start of totality. And I mean precisely then. Below is a shot from just a couple of seconds before, with the diamond ring effect haloed by the tail-end wisps of cloud. Those wisps moved out just as the moon covered the last light of the sun, and our view of totality was perfectly clear.

That photo above is my best eclipse shot. Vicki has a DSLR but I didn’t take it along. I did waste a few seconds, but only a few, trying to get a couple of HDR shots with my iPhone, but they didn’t really come out. I had read plenty of horror stories of people who basically missed their first eclipse messing around with cameras, so I resolved long ago that if I was lucky enough to have clear skies for totality, I’d try to spend them looking, not shooting.

For the most part, the partial phases of the eclipse were familiar to me from the 2012 and 2014 eclipses. Totality was a whole ‘nuther beast. This was my first total eclipse, and even though I had read a lot of eyewitness reports and seen some videos of other total eclipses, several things surprised me:

  1. Neither of my previous eclipses had been close enough to total to produce the weirdly sharp shadows that you get on either side of totality, when the thin crescent sun acts more like a point source than a bright extended object. So I’d never seen that effect before, and neither had anyone that I was with. We had fun marveling at our shadows, but I didn’t think to get any pictures or video of them. You can see the sharp shadows starting at 1:25 in this video.
  2. It got a lot darker a lot earlier than I expected. This was especially true in the last 10 minutes before totality. It was extremely weird – before the dreadnought cloud moved in, we were all aware of standing in direct sunlight, just not much of it. It wasn’t like diffuse sunlight coming through clouds, and it wasn’t like sunset light, either. I’ve never seen anything else quite like it – which I guess is part of the reason people chase eclipses, to see things you can’t see any other way.
  3. The inner corona was a lot brighter than I expected. I couldn’t really see any of the outer corona, just a thin bright ring around the moon. It was bright white. The contrast between the blazing white of the corona and the absolute blackness of the moon made the latter even more unearthly. In Seeing in the Dark, Timothy Ferris described the moon during totality as an “awful black ball” and I can now vouch for the accuracy of that description. It doesn’t look right.
  4. Even at the midpoint of totality, the sky was brighter than I had thought it would be, and the ground was darker. We all did look up, and saw Venus, Mars, Mercury, and Regulus, but I didn’t see any other stars; the stars didn’t ‘come out’ as I had expected. In contrast, right where we were, looking around at family members and other eclipse chasers, it was dark, like being outside half an hour after sunset. And the 360-degree twilight lit the horizon all the way around in shades of orange, salmon, pink, and violet. In general, the terrestrial effects of the eclipse were more pronounced and arresting that what was going on in the sky – with the undeniable exception of that awful black ball.
  5. I assume that the atmospheric effects on either side of totality are symmetrical – that the weird light I mentioned above in point 2 extends just as far after totality as before, and that the 360-degree twilight extends just as far before totality as after. But that’s not how I perceived them. I noticed the oddly thin light before totality, and after totality had ended I was surprised at how long the sunset effect persisted. The above photo is from a minute and a half after the end of totality, looking north-northeast, about 90 degrees off the path of the shadow, and the twilight effect is still visible in the distance.

After Totality

Totality was a rush. In the aftermath we sat around talking happily about how amazing it had been, and watching on the sun funnel as the moon gradually uncovered the sun. London and I made pinhole projections – his is above, mine below.

We also wandered around until we found a cottonwood that was projecting crescent suns on the street. Here’s a photo:

And a video – this worked out better than expected, because the wind was blowing the leaves and branches around and making the crescent suns flicker, like sunlight glinting off moving water. Shame I didn’t think to turn the phone sideways, but I’d just had my mind blown, so I’m giving myself a pass.

All too soon it was winding down. The telescope and sun funnel had been the first things set up when we rolled in, and they were the last things put away when we left. Here’s my last shot, from 1:16 PM:

Ironically, after all the gloomy predictions, traffic was worse getting away from the eclipse than it had been getting to it. I’d hoped that maybe we could head south out of Alliance and fast-track it back to Ogallala on Highway 26, but that way was jammed up. So we went back the way we came. On the drive home we were the 5th and 6th vehicles in a train of 17, and we had to settle for a bit under 60 mph, but we still made it back in good time. There was another train blocking the access into Lakeside, so I still don’t know if the town has a public restroom.

The trip had one neat little coda. On the flight home, London had the window seat, and he spotted the young crescent moon, back in the evening sky after its big adventure. I passed him my phone, and he got some great shots. Here’s the best:

What now?

There will be other solar eclipses between now and the next “Great American Eclipse” of 2024, but most of them will happen in other parts of the world, and the chances that I’ll have the opportunity to go see them are slim. Here are the upcoming eclipses and transits that I am hoping to observe in the next decade – as always, assuming the skies cooperate:

  • January 31, 2018 – total lunar eclipse
  • January 21, 2019 – total lunar eclipse
  • November 11, 2019 – transit of Mercury
  • May 26, 2021 – total lunar eclipse
  • May 16, 2022 – total lunar eclipse
  • November 8, 2022 – total lunar eclipse
  • October 14, 2023 – annular solar eclipse
  • April 8, 2024 – total solar eclipse
  • March 14, 2025 – total lunar eclipse
  • March 3, 2026 – total lunar eclipse

That’s a pretty good lineup, I think. For more details on all of these events, see MrEclipse.com.

In sum, the eclipse was awesome, in every sense of the word. I get now why people become eclipse chasers. I’m not quite to the point where I can afford to go jetting around the world to catch every single one, but I will make it to every future eclipse that I can. If you ever get a chance to stand in the path of totality, go.

UPDATE 29 August: Mike’s comment below about Cthulhu reminded me that I needed to post another picture. After I put the diamond ring photo on Facebook, my friend Jarrod posted this modified version, which I can’t unsee. Cower before Ecl, the Dragon of Totality:

Eclipse dragon

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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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Observing Report: more Messiers at the Salton Sea

March 21, 2017

I went to Mecca Beach again Saturday evening. Like my run at the end of February, it was a solo mission, decided on at the last minute. I made up my mind in the mid-afternoon and I emailed a few folks to see if anyone was interested, but that proved to be too little notice (not surprisingly).

I got a late start, didn’t arrive until about two hours after sunset, and there was a cloud bank to the west, so I missed out on all of the early evening Messiers. I skipped right over the winter objects, having spent the last 6 weeks observing them repeatedly with a variety of instruments.

Gear

I’m flying to Texas this weekend for a Messier Marathon star party – more news on that soon – and I’m taking the Badger along. I’ve flown with little Maks and with an AstroScan once, but this will be my first time flying with a refractor. I’ve had this trip in mind for a while – it’s why I was so excited to find that the Badger would ride securely and comfortably on my Manfrotto CXPRO4 plus DwarfStar rig, because that is an eminently flight-worthy mount and tripod combo. BUT the previous testing was just a short session in the driveway. I was curious to see how the Manfrotto/DwarfStar/Bresser setup would fare under semi-realistic conditions, on an extended observing run at a distant site.

I was also testing eyepieces. I want a travel setup that will be lightweight and low hassle, but that will still cover all the things I’m likely to want. My prime mover is the 28mm RKE. It is simply delightful and gives a bright view of a wide swath of sky. Next up is the Celestron 8-24mm zoom eyepiece, which covers most of the useful magnification range for this scope (19x-57x). I used this eyepiece a lot right after I got it. Then I was off it for a while – I went through a phase of doing a lot of high-power work with my Apex 127 and C80ED, and I thought (and still think) that the Celestron zoom was just a hair less sharp than the best of my non-zoom eyepieces, particularly the Explore Scientifics. However, my eyes are now the weakest link in the optical chain, even with glasses. So although I don’t get super-sharp pinpointy star images anymore (or at least, not until I get new glasses), I also don’t worry too much about whether my eyepieces are 100% sharp or only 97%.

I also auditioned some possible third players: the 32mm Plossl, just in case I needed more true field than the 28mm RKE will give; the 5mm Meade MWA for ‘high-power’ work (still only 92x); and the 2x Shorty Barlow. It turns out that I don’t need any more field than the 28mm RKE gives, so the Plossl is staying home; the MWA is nice but big, and not worth the bulk on this trip; and my Shorty Barlow has ever-so-slightly misaligned barrel pieces, so it won’t sit all the way down in the focuser. I’d noticed this before, but it didn’t bother me because all of my other eyepieces would come to focus anyway, but not, it turns out, the Celestron zoom. So the Barlow is staying home, too, and I’m planning to roll with just the 28mm RKE and the Celestron zoom.

Star Testing

I spent the first hour on just four targets: the Trapezium in Orion, the Pleiades, Jupiter, and Polaris. I looked at the Pleiades just to see them before they went down into the cloud bank over Palm Springs. The other three targets were to test the scope and the skies. The seeing was a little better than it has been for most of this spring, but still only so-so. The Trapezium was bouncing around too much for me to resolve the E and F components, although I suspected E a couple of times.

Jupiter looked a lot better than it has so far in this scope. I think that was partly a little better seeing, and partly the result of having collimated the scope. As I mentioned in the last post, the view of Jupiter at 92x was mesmerizing, with finely-divided belts and zones resolved all the way to the poles. I was using the 60mm aperture mask to knock down the CA, and that might have helped with the seeing and with other aberrations.

When I had stared at Jupiter for about 20 minutes, I removed the aperture mask and did a proper star test on Polaris. I’m not an expert at star testing but I know a little, and I have a copy of Suiter’s book, Star Testing Astronomical Telescopes, on loan from a friend in the club. I sketched the results inside and outside of focus and compared them to the diagrams in the book when I got home. The scope has about 1/4 wave of spherical aberration. That’s not great – it’s flirting with being not diffraction-limited, and it helps explain the scope’s so-so performance on solar system objects and double stars. On the upside, the perfectly-concentric diffraction rings confirmed that the scope is now in good collimation.

Binocular Messier Hunting

The best sky conditions of the evening were in the hour on either side of midnight. The cloud bank to the west was still there, but it had retreated down near the horizon. Transparency was as good as it was going to get. Lying down in a lounge chair and looking up naked-eye, I could make out sixth-magnitude stars at the zenith. After spending a good chunk of time at the telescope looking closely at a handful of objects, I was ready for a change of pace. I grabbed the 7×50 binoculars that came with the Bresser Comet Edition package and hopped in the lounge chair for a Messier tour.

I started with some galaxies in Ursa Major. M51, M81, and M82 were all easy, as were M94 and M63 in Canes Venatici. Then I jumped over to Corvus to pick up M68 and M104. After that I went to Coma Berenices and spent a while just staring into the Coma star cluster. It’s a true open cluster, and it looks huge because it is only 288 light years away. That’s farther than the Hyades (~150 light years), but closer than the Pleiades (380-440 light years, depending on the source), and the size of the Coma cluster is nicely intermediate between those two as well.

My first Messiers in this area were the globular clusters M3 and M53. Both were easy catches, and M3 was so bright I had to look twice to make sure it wasn’t a star. Seeing them in binoculars brought back fond memories of the very first time I ever observed them. It was the spring of 2008, and we were still living in Merced. I was on a backyard campout with London, who was only 3 1/2 years old. We were using my old dome tent, and as soon as London went to sleep I poked my top half out onto the grass and did some binocular stargazing. That was the first time I ever saw M3 and M53 with my own eyes.

My next target was the galaxy M64, and it was bright and obvious – so much so that it seemed to pop out from the background, the way that planetary nebulae sometimes do. M65 and M66 were not so pronounced but they were still easy prey. M95, M96, and M105 took a little more work and chart-checking, but I managed to bag them all. Later in the morning, after I’d gone back to the scope, I picked up the globular clusters M13 and M92, and the open clusters M6, M7, and M11.

I know that other observers have seen all 110 Messier objects with 7×50 binoculars – Jay Reynolds Freeman reports having done so in his essay, “Messier surveys“. I’ve seen all of the Messiers in my 15x70s and most of them in 10x50s, but I’ve never even attempted them in 7x binos. So I am working on a proper Messier survey with these 7x50s, and so far I’m up to 40 objects. Here’s my visual log – I’m highlighting objects in green as I observe them:

If you’d like a similar record sheet for your own observations, here’s a blank one:

A Varmint of the Skies

After an hour of binocular observing, I was ready for a stretch, and also champing to track down some of these objects with the scope. I had gotten through most of them with the scope, and I was about to make my assault on the Virgo galaxies when the moon rose.

I thought that contrast had dropped off a bit, and I was seeing fewer faint stars, and the rising moon made the reason clear: a high, thin haze had developed over most of the sky. Galaxies that had been dead easy in the binoculars just an hour before were now completely invisible in the scope. I missed out on M63, M94, and M101, and abandoned my Virgo galaxy hunt. I watched the moon rise through my binoculars, then I switched to double stars for a while. I’m not going to say much about that right now – suffice it to say that the results of my double star observing will be coming to a newsstand near you this fall.

After I’d done my double star ‘homework’, I was feeling very pleased. At the start of the evening I’d written down three goals for the session: “Messiers, double stars, chill”. With the first two activities done to my satisfaction, I was content to engage in the third. I spent more time looking at Jupiter and the moon through the scope, and a fair amount of time just sitting on a picnic table and looking up with my naked eyes. The haze had thinned out somewhat by 3:00 and I was just happy to be out under the stars. Although there were people camped just a few hundred feet from me, I had the place all to myself. Even the coyotes had stopped yipping and howling.

Back at the scope, I spent a while looking around in Lyra. My favorite astronomical axe to grind is that the “celestial sphere” compresses almost limitless space and time into what looks like a dome over our heads. As I put it in this article (and this even earlier blog post), I’m constantly trying to “shatter the bowl of the sky, to see space as space”. Lyra is a good area in which to do this, with objects as close as Vega – a scant 25 light years away – and as distant as the globular cluster M56, which lies 33,000 light years away. I’ll probably write a whole post about that soon (UPDATE: hey look, I did!).

Usually if I’m up that late at this time of year, I go through the “steam from the teapot” Messiers in Sagittarius and Scutum. But an unfortunate cloud was camped out in my way. I did pick up M11 in Scutum, and M6 and M7 near the ‘stinger’ of Scorpius, with both the binoculars and the scope. I also had a nice long look at the False Comet cluster near Zeta Scorpii. The False Comet is a fantastic object for binoculars and rich field scopes – or maybe I should say “a fantastic set of objects”, since it includes the open clusters NGC 6231 and Trumpler 24, and other bright stars in the Scorpius OB1 assocation, of which both clusters are members.

I’m up to 43 Messiers with the Badger. There are 3 objects that I’ve seen in the Bresser binoculars but not yet in this scope: M63, M94, and M101. And there are 6 that I’ve seen in the scope but not yet in the bins: M5, M29, M39, M56, M57, and M79. I’m not worried about the mismatch – most of the objects I haven’t seen in the binoculars because I just haven’t tried yet. Although I am a little nervous about my ability to distinguish the smaller planetary nebulae from stars at only 7x. Still, it’s a fun hunt and so far I’ve seen almost everything I’ve attempted. Here’s the visual tally for the scope:

I ended back in the solar system. I had a nice long look at Saturn a little after 4:00 AM, and at 4:15 I was gazing at the moon when I fell asleep. After a lifetime in academia, I’m very good at sleeping sitting up, and I didn’t realize I had drifted off until my eyebrow brushed the eyepiece, ever so gently. I think that’s the first time in almost a decade of stargazing that I have actually fallen asleep at the eyepiece. I called it a night, dragged the lounge chair around to the west side of the car where it would be out of the sun, and slept until almost 11:00.

Verdict? Well, the scope is no planet-killer. Doing the star test confirmed what I already suspected. But if I use an aperture mask and keep both the magnification and my expectations modest, it still delivers rewarding views of solar system targets. And it continues to be a fantastic wide field, low power scope for deep sky work. I was also happy to find that the light Manfrotto tripod and DwarfStar mount were more than adequate. I did have to let the scope settle a little at high power, but for Messier sweeping the whole rig just got out of the way and let me observe, which is what I had hoped for. Finally, although I had other eyepieces sitting in the rack, I spent almost the entire evening using just the 28mm RKE and the 8-24mm zoom. So as a test of my travel kit, the evening was a resounding success – and a heck of a lot of fun to boot.

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Young crescent moon, pleasant surprises, the Bresser gets a name

March 1, 2017

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Got out tonight for a few short burst of observing amidst other things. I set up the C80ED and caught the young crescent moon as it was going down. Above is my best shot. It is still wildly inferior to the one I have up in the banner image, to the right of the blog title. That one I shot with my XT6, which had about three times the light gathering ability and almost twice the angular resolution of the C80ED, and I got that shot one night earlier in the lunar cycle. That was back in the early days, when we were still living in Merced. From my driveway I had a straight shot almost to the horizon, so I could catch a 2-day old moon. Here I have lots of trees and buildings in the way, so I generally have to wait an extra night to get a shot at the moon from the driveway.

Then I was out again in the half hour before midnight to try some things with the Bresser Messier AR102S Comet Edition. First, I put it on the lightweight Manfrotto CXPRO4 tripod and DwarfStar alt-az mount that I have previously only used for much smaller scopes (example 1, example 2). Orion was going down over LA so it was pretty stinky, but I still had a long look at both the belt and the sword, and I powered up to split the Trapezium and Sigma Orionis. Then I swept up to hit M35 in Gemini, then back down to Meissa at the ‘head’ of Orion. I finished on Jupiter, using the 60mm aperture mask to knock down the CA.

bresser-on-dwarfstar-1

I was deliberately bouncing around the sky, looking at a variety of targets at a variety of magnifications, to see if the Manfrotto/DwarfStar combo would keep up. I’m a pretty forgiving observer – witness my near-pathological devotion to cheap scopes and stuff made out of junk – but one thing I just can’t handle is an undermounted scope. My first Mak was a 4″ which I hated and sold away before I realized that I hated it because I’d never put it on a solid mount. That experience left me traumatized when it comes to rickety mounts.

The Bresser/Manfrotto/DwarfStar rig doesn’t look like it should work. It looks like the definition of a spindly undermounted disaster. But it was fine. I never had any problem slewing, tracking, or focusing. It helps that the Bresser is lighter than it looks, and carbon fiber is a lot stronger than it looks.

(In the photo, I have the optional eyepiece rack attached to the DwarfStar – I don’t think I’ve ever shown a photo of the mount with it in place. It’s useful.)

I was also pleasantly surprised by the views I got of Jupiter. To get to a decent magnification I used the 8.8mm ES82, both natively (52x) and Barlowed (104x), and a Celestron 8-24mm zoom dialed down to 8 (57x). In both eyepieces I could see the North and South Equatorial Belts and stacks of minor belts marching away toward the poles. There was some CA, but I could minimize the effect by keeping Jupiter in the center of the field, and my eye centered over the eyepiece. The view was so good that I slipped out of gear testing mode and just stared for a few pleasant minutes. I was also happy to find that with the rubber eyeguard removed, I could see the entire field of the 8-24mm zoom at all magnifications while wearing glasses. Which I have to do now. In fact, the other night at the Salton Sea I made almost all of my observations with glasses on.

And lastly, the Bresser Messier AR102S Comet Edition – whew! – finally has a name. I posted on Cloudy Nights about the Messier survey I’m starting with it (thread here), and CN user ‘Glob’ wrote,

mwedel, I read and enjoy your blog, let me suggest nicknaming the 4″ “The Ferret” as King Louis XV called Messier.

I responded:

That is a lovely suggestion, and it put a huge smile on my face. One thing I haven’t blogged about yet is that basically by serendipity I managed to pick up an 80mm prototype of the Bresser ‘reflactor’. So now I have two, big and little, otherwise nearly identical. Ferrets are mustelids (weasel family), along with wolverines, badgers, skunks, fishers, martens, stoats, weasels, and otters. My late grandfather was an accomplished taxidermist and one of his stuffed badgers is sitting on top of a bookcase about four feet from me as I type. It’s just about the same size as the 4″ reflactor. So I’m going to take your charming suggestion, with one modification: the 80mm will be the Ferret, as I anticipate some effort to ferret out all the Messiers with it, and the 4″ is henceforth the Badger, because it can just knock them around with all that aperture. Thanks for helping me solve that long-standing and vexing problem!

So, it’s official now: from now on, the Bresser AR102S is the Badger, and the 80mm will be the Ferret. More info on the Ferret one of these days. I’m going out with this family photo of the two – Badger’s up front, Ferret looms behind:

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Why and how to make a sub-aperture mask for a refractor

February 11, 2017

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Here’s the Bresser Messier AR102S Comet Edition with a homemade aperture mask. I just converted the scope from a 102mm f/4.5 to a 60mm f/7.7.

“WAT!? You took a refractor, the most aperture-challenged of the three basic telescope designs, and made it even smaller?”

Yup. For several reasons.

The first and most obvious is to control chromatic aberration (CA), also known as false color. Despite the name ‘achromat’, which literally means ‘no color’, doublet refractors without extra-low dispersion (ED) glass do show some false color, because their lenses do not bring all of the colors of light to the same focus point (they’re still a LOT better than scopes with a singlet objective lens, like those used by Galileo). For dim objects like galaxies, nebulae, and most field stars, the effect is not noticeable, even in large and optically fast scopes like the AR102S Comet Edition (nickname needed). But bright objects like the moon, planets, and first magnitude stars will be surrounded by purplish halos, and may have yellowish margins. In effect, the purple and yellow-orange parts of the spectrum are forming out-of-focus images that are superimposed on the main in-focus image.

The problem is that CA gets bad fast as refractors get bigger. There are a couple of standards that are commonly used to describe the focal ratio necessary to minimize CA to acceptable levels, the Conrady standard and the Sidgwick standard. By the Conrady standard, the focal ratio must be 5 times the aperture in inches; by the less stringent Sidgwick standard, 3 times the aperture in inches is good enough. Note that the standards describe focal ratios, not focal lengths, so they go up fast with increasing aperture. Here are some apertures, focal ratios, and focal lengths required to meet the Sidgwick standard:

  • 50mm (2″) : f/6 : 300mm
  • 76mm (3″) : f/9 : 684mm
  • 102mm (4″) : f/12 : 1224mm
  • 127mm (5″) : f/15 : 1905mm
  • 152mm (6″) : f/18 : 2736mm

This, along with mounting considerations, explains why reflectors and catadioptric scopes are progressively more common past 4″ in aperture. A 6″, f/8 Newtonian will be free of false color (as are all reflectors) and has such a gently converging light cone that it is easy to collimate and to focus – it’s easy for such scopes to achieve ‘planet-killer’ status if the mirror is good. A 6″, f/8 achromat will be a beast to mount and it will show lurid false color on bright objects.

But people still make, buy, and use such scopes! Why? Horses for courses: big, fast achromats can be superb deep-sky scopes, where chromatic aberration is typically not a problem. With the fixed sizes of standard eyepieces, achieving wide true fields requires short focal lengths (not just short focal ratios), and bright images require aperture, which drives the development of large but optically fast scopes like the AR102S Comet Edition. At f/4.5, it is well into ghastly CA territory on bright targets. The other night I stayed up late to catch Jupiter, and in the AR102S the planet wouldn’t even come to a clean focus. It was just a bright ball of light inside a sea of purple. I switched over to London’s 60mm f/11 Meade refractor and Jupiter snapped into a sharp and essentially color-free focus. There was a moon emerging from behind the limb of planet, already one moon-diameter out into black space, that was completely invisible in the CA-smudged view of the AR102S.

I’m okay with that – as I noted in a previous post, observing bright solar system targets with the AR102S is deliberate misuse of the scope. When I want good planetary views, I have a 5″ Mak and a 10″ Dob that can both be pushed to 500x (assuming the atmosphere is steady enough). But their max fields of view are pathetic compared to the AR102S – about 1.1 degrees for the Mak, and a shade over 2 degrees for the Dob, versus 3.6 degrees for the refractor, which is enough to take in all of Orion’s sword at once, with space left over on either side.

Still, I’m not going to take all of my scopes out with me every time I go observing, and chances are good that at some point I’ll want to look at something bright even if my main goal for the evening was low-power sweeping with the AR102S. Under those circumstances, it’s easier to have an aperture mask shoved in my eyepiece case than to pack a second scope. Hence this project and this post.

But I’m getting ahead of myself. There are other reasons to stop down a scope besides reducing CA:

  • To reduce glare from bright objects. Mostly applies to the moon when it’s full or very gibbous.
  • To give a more aesthetically pleasing image when the seeing is bad. Opinions differ on this point. Some folks prefer to look through a larger aperture despite the increased susceptibility to bad seeing, on the grounds that in the moments when the atmosphere does settle down a bit, you’ll see more detail. I suppose it depends on whether one is in exploration mode or aesthetic observation mode.
  • To make it easier to focus. F/4.5 is a steep light cone, and it’s easy to overshoot the point of best focus. Stopping down the scope makes a shallower light cone, so it’s easier to watch the image transition from out of focus, to near focus, to in focus. I’m going to test this method of finding best focus on some close double stars.

I had done some calculations in advance to figure out what sizes of aperture masks I’d want to try out. Given that the AR102S has a fixed focal length of 459mm, here are the focal ratios at full aperture and at 10mm decrements:

  • 102mm gives 459/102 = f/4.5
  • 90mm gives 459/90 = f/5.1
  • 80mm gives 459/80 = f/5.7
  • 70mm gives 459/70 = f/6.5
  • 60mm gives 459/60 = f/7.7
  • 50mm gives 459/50 = f/9.2
  • 40mm gives 459/40 = f/11.5

3-inch-sub-aperture-mask

I didn’t want to trade away too much resolving power, so I tested the scope on the moon using cardboard masks of 76mm and 60mm, made from the light cardboard spacers from a box of wet cat food. The 76mm is shown above. Perhaps unsurprisingly, at this aperture and focal ratio (f/6) the view was still unappealingly soft. But 60mm looked good, with minimal CA. This makes sense – the working focal ratio of f/7.7 is a healthy step beyond the f/7.2 that the Sidgwick standard suggests for a 60mm aperture. Going any smaller would be trading away valuable resolution, without significantly improving the image.

60mm-aperture-mask-1-gallon-jar

The light cardboard aperture masks were fast and easy to make, but they weren’t very sturdy. To make a more permanent mask, I needed plastic, heavier cardboard, or foam-core board. So I unscrewed the dewshield from the scope and walked down to the dollar store, where I looked for food packages and storage containers that might fit. Finally on the last aisle I found this 1-gallon plastic jar. The lid slip-fit over the dewshield with just a bit of extra room, which I knew I could shim out with some sticky-back felt.

60mm-aperture-mask-2-marking

I wanted to make sure the lid would fit before I did the hard work of cutting, so I put the felt on first. This was very familiar – it seems like every other scope I get has a loose dust cover that has to be shimmed to fit correctly. I’ve been slowly chipping away at the same package of sticky-back felt since 2010. I didn’t have a compass handy, so I used a small paper ruler to make a ring of marks around concentric 60mm circle inside the lid. Then found a lid to a jar of vitamins that was exactly 60mm in diameter and used that to trace the circle neatly.

60mm-aperture-mask-3-completed-mask

I was going to cut out the aperture using hobby knife, but the plastic was too tough. So I moved up to a box knife, and then a linoleum knife. Then I said heck with it and got the Dremel. The hole I cut wasn’t perfectly circular and had rough edges to boot, so I wrapped some sandpaper around a pill bottle to make a tool for rounding out the aperture.

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Here’s the scope before…

60mm-aperture-mask-5-comet-edition-after

…and after.

Even with the aperture mask, the AR102S is not a champion scope on solar system targets. The C80ED blows it away, which makes sense – it has a 33% resolution advantage over the stopped-down AR102S, and frankly just better glass. But at least the view now is clean and not appallingly degraded. A dramatic way to see the difference is to get a good tight focus on the moon with the mask on, then quickly take it off without removing one’s eye from the eyepiece, and watch the view get a lot brighter and a lot softer at the same time.

I have a few more things I want to do. The 60mm aperture mask fits over the end of the scope so securely that it could work as a dust cover, if only I can find or make something to plug the central hole. Also, I think I am going to play with making aperture masks in other sizes, just to see what happens.

And finally, I have another 4″ scope that will be fun to make an aperture mask for. But that will be a subject for another post.
skyscanner-aperture-mask-test-fit-jar-lid

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Misusing a fast reflactor: moon-gazing with the Bresser AR102S Comet Edition

February 1, 2017

bresser-ar102s-comet-set-up-for-moongazing

I was going to hold off before I posted anything on the performance of the Bresser Messier AR102S Comet Edition (which I swear I am going to start calling something else, just as soon as I think of a good nickname). That’s because I haven’t had a chance to try it out under the conditions where it is likely to do well. This is an optically fast scope, optimized for low-power, widefield scanning, ideally under dark skies where those faint stars can really pop. A great time and place to test-drive this scope would have been last Saturday night at the Salton Sea, right after the new moon, when Terry Nakazono and I stayed up observing almost to dawn, (expect that observing report in the not-too-distant future).

Unfortunately, the scope arrived Sunday afternoon, a day late for our Salton trip. Mount Baldy is covered in ice and snow, and I haven’t had time on these school nights to get up there anyway, much less to get to anyplace farther away. And the skies down here in Claremont have been crappy this week. Never clouded out, but never truly clear either – there has been a thin, high-altitude haze that is really good at both obscuring dim stuff and reflecting light pollution. So the only objects that have looked good are the bright, small things – the moon, Venus, Jupiter, and double stars. In other words, exactly the things that the AR102S Comet Edition is not specialized for.

So I don’t feel like I can give the scope a fair review yet, because all I’ve been able to do with it are the things it’s not built for. It’s like taking a Lamborghini Huracán on a Moab jeep trail – it’s not going to work out well, in ways that are completely predictable, and you’re not going to learn very much by doing it.

But when has that ever stopped me? I may not be able to review the scope, but I can still play around with it.

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Here’s a raw shot of the moon, taken with a Nikon Coolpix 4500 shooting afocally (and handheld) through the supplied 20mm 70-degree eyepiece.

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Same shot tweaked with Unsharp Mask and Curves in GIMP.

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And then converted to black and white.

I didn’t learn much. Yes, there is chromatic aberration. In other news, water is wet and the Pope is Catholic. On the plus side, the Trapezium in Orion is split into four members at 23x. Haven’t tried it on the Double Double or any other double stars, really.

On the to-do list are (1) to get this scope out someplace dark and clear and really put it through its paces, at a variety of magnifications – and using a variety of eyepiece designs – on a variety of targets, (2) to do some actual testing on close double stars and doubles with significant magnitude differences, and (3) to experiment with sub-aperture masks to knock down the CA on bright stuff. “Why not just use a smaller or better-corrected scope?” you may wonder. Well, this is sold as a travel kit, and if by using a sub-aperture mask I can make it into a passable solar system scope, I’ve just made it a better all-rounder when and if I take it on the road.

Given the waxing moon and the continuing lousy forecast for the coming week, I’ll probably have to tackle that to-do list in reverse order. Stay tuned.

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Parting shot. I got this Earthshine pic by doing a half-second exposure with the Coolpix. It’s not nearly as good as the one in the banner at the top of the page. I need to try again next cycle when the moon is younger.

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Small, medium, large – observing near and far in the last two weeks

June 4, 2016

Matt at Delicate Arch IMG_2984

Preface – Running with the Red Queen

I’ve just finished maybe the busiest spring of my life. January and February were largely sunk into day-job work – time-consuming, but necessary, interesting, and in fact rewarding. Then the last three months have been taken up with travel and public lectures.

  • In March I went to Oklahoma for 10 days of paleontological research in field and lab, and I gave a talk at the Oklahoma Museum of Natural History titled, “Dinosaurs versus whales: what is the largest animal of all time, and how do we know?”
  • In April I did a two-day trip to Mesa, Arizona, for more paleo work. No talk on that trip, but I did participate in the “Beer and Bones” outreach at the Arizona Museum of Natural History.
  • In early May I was in Utah for another 10 days of paleo research, and I gave a talk at the Prehistoric Museum in Price on, “Why elephants are so small”. My colleague Mike Taylor and I took one day off from dashing through museums to tour Arches National Park, which is where Mike took the photo at the top of the post.
  • Last weekend I was up at RTMC, where I gave a Beginner’s Corner talk on, “The scale of the cosmos”.

I’m not complaining – far from it. It’s been exhilarating, and the collaborative work I have rolling in Oklahoma and Utah will hopefully be paying off for years. And planning and executing all of the work has been satisfying. Particularly the RTMC talk, which deserves a whole post of its own. And ultimately this is all stuff that I chose to do, and if I could do it all over again, I would.

BUT there have been consequences. Most frustratingly, I haven’t had enough uninterrupted time to get anything written up for publication – not the sizable backlog of old projects I need to get finished up, and not the immense pile of new things I’ve learned this year. I haven’t gotten out to observe as much as I’d like, and I’ve barely blogged at all.

And it’s not over. In two weeks I leave for a week of paleo fieldwork in Oklahoma, then I’m back for a week, then I’m off to Utah for about 10 more days of digging up dinosaurs. In between I’ll teaching in the summer human anatomy course at WesternU.

But I’ve had a nice little pulse of observing in the last couple of weeks – two weekends ago up at Arroyo Grande, near San Luis Obispo, last weekend at RTMC above Big Bear, and this week at Santa Cruz Island off the coast. No time for separate observing reports, so I’m combining them all into one.

Observing Report 1 (Medium): The Planets and Moon from Arroyo Grande

I was fortunate to be part of a great, tightly-knit cohort of grad students at Berkeley. Of the people I was closest to, some are still in and around the Bay Area and some of us have been sucked into the gravity well of the LA metro area. Occasionally we get together somewhere halfway in between, either up in the Sierras or near the coast. I usually take a telescope, because almost everywhere is darker than where I live, and when I’m traveling by car there’s simply no reason not to.

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This year we met up for a couple of days and nights in Arroyo Grande. We hiked in the hills, went down to Morro Bay to watch ocean wildlife and buy seafood, played poker, and generally got caught up on work, family, hobbies, and life. Our first night was wonderfully clear. I had along the trusty C80ED, which has become my most-used scope. It’s mechanically rugged, optically damn near perfect, and compact enough to not require much time or thought when it comes to transportation and setup. On Saturday, May 21, we spent some time with Jupiter, Mars, and Saturn. Jupiter and Saturn were as they always are: beautiful and surprising in their immanence. I cannot look through the telescope at either of them without being forcefully reminded that they are as real as I am, that as I go about my days full of busyness and drama, they are always out there, hundreds of millions of miles away, go about their own business whether I or anyone else pay them any attention or not. One of my friends had never seen the rings of Saturn with his own eyes, so that was an added bonus.

Mars was the real treat. Using the Meade 5mm 100-degree EP and a Barlow I was able to crank up the magnification to 240x. The dark dagger of Syrtis Major and the white gleam of the north polar cap were both obvious. It is always arresting to see details on this world that has loomed so large in the human imagination, from ancient mythology to science fiction to current and future exploration.

The next night we sat out on the patio, eating oysters and watching the sun set. I didn’t have any of my own binoculars along, but a friend had brought a couple, and after it got dark we watched the still-mostly-full moon rise through the trees on the ridgeline to the east.

It was all shallow sky stuff (solar system, that is), but it was all spectacular, and I’m glad we did it.

Observing Report 2 (Large): Going Deep at RTMC

Last weekend I was up at RTMC, finally. I’ve been wanting to go since I got to SoCal, but in the past it’s fallen on the same week as our university graduation and I’ve been too wiped out. I didn’t make it up for the whole weekend. We went up as a family to stay Saturday and Sunday nights. I went up to RTMC early Sunday morning to look around, give my talk, and hang out. Ron Hoekwater, Laura Jaoui, Jim Bridgewater, Ludd Trozpek, and Alex McConahay of the PVAA were all there and we spent some time catching talks and jawing about skies and scopes. I also chatted with some folks from farther afield, including Arizona and NorCal.

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I took off in the afternoon to spend time with London and Vicki, then went back up after dinner. All I had along were my Celestron 10x50s (yes, those), but Ron had his 25-inch Obsession dob, and he was content to use it as the centerpiece of a group observing session. We looked at the planets, or at least Jim Bridgewater and I did – Ron had checked them out the previous night and didn’t want to blow out his dark adaptation. That was a smart call, as the Obsession gathers a LOT of light and the planets were almost blown out. We could have put in a filter, but ehh, we had other things to be getting on with.

We started with globular clusters. M3, M5, M53, NGC 3053, and one or two other distant NGC globs. The close ones were explosions of stars that filled the eyepiece. The distant ones shimmered out of the black like the lights of distant cities. Then we moved on to galaxies. M81 and M82 were bigger, brighter, and more detailed than I had ever seen them. M51 was just stunning – the spiral arms were so well-defined that it looked like Lord Rosse’s sketch.

M51 sketch by Lord Rosse

As nice as those were, the Virgo galaxy cluster was better. There were so many galaxies that identifying them was a pain – there were so many little NGCs in between the familiar Messier galaxies that my usual identification strategies kept getting derailed. It was kind of embarrassing, actually – I did just write an article about this stuff. But also incredible. NGC 4435 and 4438 – the pair of galaxies known as “The Eyes” – were so big, bright, and widely separated that I didn’t realize I was looking at them until the third or fourth pass.

We finished up on planetary nebulae. The seeing was good but not perfect – the central star in the Ring Nebula was visible about a quarter of the time. The Cat’s Eye, NGC 6543, was a fat green S with a prominent central star – it looked like it had been carved out of jade.

An evening under dark skies with a giant scope is both a blessing and a curse. A blessing because you get to see so many unfamiliar objects, and so many details in familiar objects, that are beyond the reach of smaller scopes. A curse because by the end of the session you may find yourself thinking, “Sheesh, why do I even bother with my little 3-, 5-, and 10-inch scopes?”

Fortunately another observing experience, one that would remind me of the joys of small-aperture observing, was right around the corner.

Observing Report 3 (Small): A Binocular Tour of the Spring Sky

My son, London, is finishing up fifth grade at Oakmont Outdoor School, one of the half-dozen or so different elementary schools in the Claremont Unified School District. We were fortunate when we moved to Claremont to land just a couple of blocks from Oakmont – we would have been happy to land within walking distance of any of the schools, but if we’d had our choice we would have picked Oakmont anyway, since we wanted to raise London with as much exposure to the outdoors as we could.

Oakmont’s slogan is, “Learning in the world’s biomes”. The major activities of each grade are organized around a particular biome, and so is the end-of-year field trip. In third grade, the kids went to Sea World. Last year it was the desert by Palm Springs for a 2-day, 1-night trip. This year it was Santa Cruz Island, in Channel Islands National Park, for a 3-day, 2-night trip. Parent chaperones are needed and I’ve been fortunate to get to go every year.

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The island was amazing. We saw dolphins, sea lions, and petrels on the boat ride out – I took the photo above from the prow of the ship – more sea lions, seals, pelicans, cormorants, gulls, and red pelagic crabs at the shore, and dwarf island foxes, ravens, and the occasional hawk inland. On the final evening, June 2, we hiked up to the top of the cliffs to watch the sun set over the Pacific, which was one of the most beautiful things I have ever seen in my life. I didn’t know it at the time, but I’d see something even more beautiful just a few hours later.

I had binoculars along – Bushnell 10×40 roofs that I got specifically for daytime use, and which I had used a lot on the trip already to watch wildlife. When we got back to camp, a few of the teachers and hung back and started talking about the planets, bright stars, and constellations. I started pointing out a few of the brighter targets and passing around the binoculars, and we ended up having an impromptu binocular star party. (The kids and a fair number of the adults were all exhausted from a full day of hiking, and sensibly went to bed.)

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What followed was one of the best and most memorable observing sessions of my life. The only permanent residents of Santa Cruz Island are a couple of National Park employees, and they turn their lights off after dark. We got a little light pollution on the eastern horizon from Ventura and Oxnard, some 20 miles distant, but for the most part the sky was darkAfton Canyon dark, Hovatter Road dark – what I typically refer to as stupid dark.

We roamed all over the sky, looking at targets large and small, near and far, bright and dim. I didn’t keep track as we were going, but I wrote down a list yesterday morning on the boat ride back to the mainland (we went through a fog bank and only saw a handful of dolphins, so I had plenty of time).

In the northern sky:

  • Polaris and the Engagement Ring asterism
  • Mizar and Alcor
  • M51 – yes, it was visible in the 10×40 bins
  • The 3 Leaps of the Gazelle

In the western sky:

  • M44, the Beehive – easily visible to the naked eye, and just stunning in the binos
  • Leo
  • Coma Berenices star cluster
  • Virgo/Coma galaxies – identifications were tough, but a few were visible

In the eastern sky, Lyra had just cleared the trees when we started observing (at 9:15 or so), and all of Cygnus was above the trees when we finally shut down at 12:45 AM. In addition to tracing out the constellations, along the way we looked at:

  • Epsilon Lyrae, the Double-Double star
  • Albireo
  • Alpha Vulpeculae (the subject of my Binocular Highlight column in the ### issue of Sky & Telescope)
  • Brocchi’s Coathanger (Collinder 399)
  • Sagitta (just traced the constellation)
  • M27, the Dumbbell Nebula
  • Sadr and its surrounding ring of stars in the heart of Cygnus
  • NGC 7000, the North American Nebula – this and the Northern Coalsack were easily visible to the naked eye once Cygnus has risen out of the near-horizon LP

…and we just cruised the Milky Way from Cygnus to Cepheus, not singling out individual objects but just taking in the rich star fields.

But the southern sky was the best. Looking south from Santa Cruz Island, there’s only open ocean, broken here and there by other, distant islands and ultimately by Antarctica. It reminded me of looking south from Punta del Este in Uruguay, only I was in a valley instead of on a beach. The ridgeline to the south did cut off a bit of the sky, but we were still able to see all of Scorpio, including the False Comet, made up of NGC 6231 and Trumpler 24, which was one of the highlights.

It was trippy watching the Milky Way rise. I usually look at the summer Milky Way when it is higher overhead. I usually have to do that, because the objects aren’t visible in the near-horizon haze. But from Santa Cruz Island, things were not only bright but obvious as soon as they cleared the ridgeline to the south. It’s almost pointless to list them – we saw every Messier object in the “steam from the teapot”, from M7 and M6 in the south to M11 in the north, plus a lot of NGCs, plus star clouds and dark nebulae almost beyond counting. They were all great through the binoculars – M7 was a special treat, like a globular cluster on a diet – but honestly the best views of the night were naked-eye.

I realized that I am just never out observing the Milky Way at this time of year. My regular desert observing spots are all too hot in the summer, and when I do go there is often at least some light pollution to the south (El Centro from the Salton Sea, Barstow from Owl Canyon, etc.). I do most of my deep and dark observing in October and November, when the southern Milky Way is setting, not rising.

So I was completely unprepared for how much detail would be visible to the naked eye. When the Milky Way rose, it didn’t look like a band of light, it looked like a galaxy. I searched through a lot of photographs of the rising Milky Way to find one that approximated the naked-eye view, and this is the closest I got:

I am not exaggerating – the bright and dark areas were that defined. The Great Rift was visible from Cygnus to the horizon, and its southern border was notched by distinct deep sky objects from Aquila onward. The Scutum Star Cloud, M16, M17, M24, M23, M8, M6, M7, NGC 6281, and the False Comet were all easily visible to the naked eye as a chain of luminous patches against the dark dust lane of our own galaxy. In fact, I noted NGC 6281 with my naked eyes first, thought, “What the heck is that?”, and had to look it up. We also caught M4, M22, M23, and M25 in the bins, plus a bundle of dark nebulae that I’d never noted before and didn’t bother keeping track of.

Longtime S&T contributor Tony Flanders (now retired but still writing occasionally) is active on Cloudy Nights, and his sig file reads:

First and foremost observing love: naked eye.
Second, binoculars.
Last but not least, telescopes.
And I sometimes dabble with cameras.

Until fairly recently I would have listed my own preferences in reverse order, from telescopes to binos to naked eye. That may sound odd for a “bino guy”, which I guess I am since all of my ‘professional’ astro-writing has been binocular-based. But it’s true – as much as I love binoculars, I would have picked a telescope first. But I am – gradually, belatedly – waking up. In some ways, it would have been great to have a scope, any scope, along on the island trip. I’m sure that even the C80ED would have taken us crazy deep, considering what we could see with a pair of low-end 40mm roof-prism bins. But it would also have come between us and the sky, and I would have spent more time futzing with eyepieces and less time just looking up.

This was a surprising and welcome realization, coming so shortly on the heels of a frankly astonishing session with Ron’s 25-inch dob at RTMC. I was worried that big-telescope observing might spoil me, but that fear turned out to be unfounded. All I need to be happy is a dark sky. If I have some people to share it with, even better. Anything more is just cake at the end of an already long buffet.

Let’s eat.