It’s late and my computer is almost dead, so I’m just going to link to the longer announcement/acknowledgment post on my paleontology blog. Enjoy!
It’s late and my computer is almost dead, so I’m just going to link to the longer announcement/acknowledgment post on my paleontology blog. Enjoy!
I’ve been interested in Orion’s SkyScanner 100 tabletop Dob ever since 2012, when I got to look through the SkyScanners owned by Terry Nakazono and Doug Rennie. In particular, the evening I spent stargazing with Doug up in Oregon that October is in my short list of all-time favorite observing sessions. See that observing report here, and be sure to check out Terry’s guest post on the SkyScanner 100 here.
After spending literally years contemplating the purchase, what finally tipped me into SkyScanner ownership was my own forgetfulness. On July 3 I was driving to Utah to spend 10 days hunting dinosaurs with friends and colleagues. I knew I’d want some dark-sky time so I packed my C80ED, eyepiece case, sky atlas, and binoculars. About the time I hit Barstow – just too far to turn around and go back – I realized that I’d forgotten to pack a mount and tripod. So my choices were to roll with binos only, or come up with Plan B on the fly.
The number of dedicated telescope stores on the direct route between Barstow and Moab continues to hover near zero. However, I was already planning to pass through Flagstaff, which has the Lowell Observatory, which has a gift shop. I called ahead: did they have any telescopes in stock? Why, yes, the Orion XT8 and SkyScanner 100, and both were 10% off as part of a holiday weekend promo. Not long after, I had a SkyScanner in the back seat of the car and a song in my heart.
I spent that first night in Bluff, Utah, after having driven through Monument Valley, which I’d never visited before. Bluff is truly remote – the nearest towns with more than 5000 people are Moab (5046), 100 miles north, and Kayenta, Arizona (5189), 68 miles southwest. So the skies are inky dark. I rolled in pretty late and I really needed to get some rack, but there was zero chance that I was going to pass up first light for the SkyScanner under those jet-black southern Utah skies. I drove about five miles outside of town and pulled over on a dirt road.
The sky was just incredible, even better than out on Santa Cruz Island back in June. Again, the Milky Way looked like an astrophoto and the Messiers in Scorpio, Scutum, and Sagittarius were almost all naked-eye visible (minus a few of the minor globs). I did look at a handful of things with the SkyScanner, and they all looked fine, but honestly I spent more time with my 10×42 binos and even more time than that just staring around with my naked eyes. In skies like that, a telescope can almost be a distraction.
Still, I’m glad I got that first light session in on the evening of the 3rd, because opportunities would be thin for a while. I did set up the scope on the 4th of July, on the trunk of the car in the driveway of my friends’ place in Moab, and we looked at a few things, but everyone was pretty pooped after a day of hunting dinosaurs and partying so we didn’t push very late. And after that, the sky was at least partly cloudy for most of a week.
Finally on the evening of July 10th we got nice, clear skies. I drove out southeast of Moab on the La Sal Loop Road with a couple of new friends and we spent a very pleasant couple of hours rocking through the best and brightest. The SkyScanner performed like a champ.
I’ve only had it out a couple of times since betting back to Claremont, both times for quick peeks. As a grab-n-go scope it is, as far as I’m concerned, unparalleled. With an assembled weight of just over 6 lbs, it is the definition of a one-hander. The tabletop tripod works great, very smooth, and the rubber feet provide a good grip even on the precarious edge of a sloping car hood. And it goes on my Manfrotto tripod (3.5 lbs) for a 10-pound setup that’s perfect for a long session seated or standing.
As you can see from the photos (kindly provided by Terry Nakazono), I took the SkyScanner to last Friday night’s meeting of the Pomona Valley Amateur Astronomers, where it drew a lot of interest. I was going to set up the scope outside after the meeting so we could all have a look at Saturn, but the night sky was almost completely blocked out by smoke from the wildfires and the air quality was terrible, so we packed it in. I think I’ll get in the habit of taking the scope to meetings so we can do a little observing after – it’s always seemed to me that an astronomy club should have at least one working scope at each meeting.
Here’s my number one thought regarding the SkyScanner 100: how extremely stupid of me not to have gotten one sooner. If you’re interested in this scope and you’re on the fence, just do it. Heck, if you’re shopping for a big scope and you’re not sure what you want, get a SkyScanner to keep you busy in the meantime. It’s an insane amount of scope – and mount – for a little over a hundred bucks.
I just turned in my sixth Binocular Highlight column for Sky & Telescope. While I had everything out for the write-up, I thought people might be interested to know what sources I make use of.
Here’s the stuff I use pretty much every time:
Sources I turn to often, but not always:
To get the latest astrophysical data I turn to the web. Particularly helpful sources are the SEDS Messier database, non-Messier NGC/IC/etc page, and Interactive NGC Catalog, the NGC/IC Project, SIMBAD, the NASA Extragalactic Database, and if all else fails, Google Scholar and ArXiv.
For inspiration I’m quite omnivorous. Gary Seronik hit the Messiers pretty hard for the last few years, so I’m avoiding them for the time being, both to avoid duplication and to force myself to go find new stuff. The Astronomical League’s Deep Sky Binocular observing list (free), the Irish Federation of Astronomical Societies Binocular Certificate Handbook (free), James Mullaney’s Celestial Harvest, Phil Harrington’s Touring the Universe through Binoculars, and my own notes compiled over the past 8.5 years all serve as jumping-off points. Tom Price-Nicholson’s Binocular Stargazing Catalog (free) looks like a useful source as well, although I haven’t had a chance to explore it thoroughly yet. More often than not, I go out to find a particular object or to survey a set of objects (open clusters in Cygnus, for example) and end up discovering new things. So far I’ve been generating many more possible topics to write about than I actually can, so it seems unlikely that I’ll run out of subject matter anytime soon. We’ll see!
If you know of something I should be using that’s not on the list, please let me know – the comment field is open.
This is my Mini Museum: a collection of tiny samples of rare and interesting specimens from the history and prehistory of Earth and the solar system. There’s a lot of stuff in here that is very satisfying as both a paleontologist and an amateur astronomer. Highlights for me are the preserved woolly mammoth meat, the fiberglass casts of Diplodocus bones used as the Krayt Dragon skeleton in Star Wars: A New Hope, and, above all, the tiny piece of the Martian meteorite Zagami. It’s labeled “Martian atmosphere” because the meteor is known to contain tiny bubbles of Martian atmosphere in pockets of melted glass (Marti et al., 1995).
The specimens are embedded in a single block of acrylic that is 5 inches tall, 4 inches wide, and 1 inch thick. At $299 it’s not cheap, but it’s a pretty astounding collection of objects at any price. There is also a smaller, 10-specimen edition for $99. It doesn’t include Zagami or the Krayt Dragon, but it does have asteroid fragments, Stegosaurus plate, woolly mammoth meat, fulgurite, and the moon tree sample. These will sell out at some point, so if you’re interested in picking one up, don’t tarry.
Marti, K., Kim, J.S., Thakur, A.N., McCoy, T.J. and Keil, K., 1995. Signatures of the Martian atmopshere in glass of the Zagami meteorite. Science, 267(5206), p.1981.
In the last post I introduced my new small scope, the PICO-6 60mm Mak-Cass. After having a positive first light, I decided the scope was good enough to be the center of a new travel observing kit. Here’s the scope mounted on a Universal Astronomics DwarfStar alt-az head and a Manfrotto CXPRO4 Carbon Fiber Tripod.
Here’s the kit broken down. The case is an AmazonBasics Medium DSLR Gadget Bag, which Doug Rennie helpfully put me on to. The Pocket Sky Atlas and small Night Sky planisphere go in the back pocket. In front of the bag from left to right:
Here’s everything packed away. This was just a first pass. The final arrangement I came to is as follows:
Oh, the vertical dividers in the case are held in with velcro so they can be adjusted or removed as needed.
For flight, the tripod can go in a backpack or in checked luggage, and the AmazonBasics case goes as my carry-on “additional item”. The tripod weighs 3.5 lbs, the fully-packed case weighs 6. For a total of 9.5 lbs, I have a full-size tripod, a smooth, variable-resistance alt-az head, eyepieces giving magnifications of 22x, 29-88x, and 117x, a scope which will show the Cassini Division and split Epsilon Lyrae, a planisphere, and a mag 7.6 all-sky atlas.
This past week I was out at Black Mesa, at the northwestern corner of the Oklahoma panhandle, to dig up dinosaurs. I took the whole kit, and I used it. On Sunday night I showed half a dozen people the moons of Jupiter, the ice caps of Mars, the rings of Saturn, a couple of double stars, and the full moon. Monday night I was too pooped for stargazing. Tuesday I spend a couple of hours observing with my parents and a couple of other visitors who were also staying at the Black Mesa Bed & Breakfast. We looked at the same run of stuff as I had Sunday evening, plus a couple more double stars, the open clusterM7, and the False Comet Cluster in southern Scorpio, which is a visual amalgam of the open clusters NGC 6231 and Trumpler 24. After that, we were clouded out for the rest of the week, but it was still more than worth it to have the little scope along.
Verdict: an amazingly flexible and capable setup. I look forward to many more adventures with it.
Here’s one more shot from the road. Nothing telescopic – on Thursday morning the rising sun was accompanied by a pair of sun dogs. This is a raw shot with my iPhone 5c. The best sun dogs I’ve ever seen in my life.
This came a couple of weeks ago. I got it from Kasai Trading in Japan – here’s the link. They market both a 60mm Maksutov-Cassegrain, which is the PICO-6 shown here, and an 80mm Mak-Cass called the PICO-8. These appear to be the same scopes as those sold in Europe as the Omegon MightyMaks, which are available through Astroshop.edu (here) and Amazon.co.uk (here).
It’s been a while since I posted about small scopes, and after getting the little SV50 refractor nearly six years ago, I declared my small telescope quest complete. But the SV50 turns out to be a more satisfying finder than stand-alone scope, even for air travel. For deep-sky work when I’m traveling, I’m usually happy with binoculars (most recently on the Channel Islands), but sometimes it’s nice to check on the planets, too, and the SV50 just doesn’t have the reach.
I thought this little Mak might be just the ticket. As you can see, it is tiny. It weighs just a bit over 1 pound. Here it is with a regular-sized beverage bottle and my largest eyepiece, the 2-inch 32mm Astro-Tech Titan.
And here it is next to the SV50. The SV50 has a focal length of 210mm and a focal ratio of f/4.2. The PICO-6 has a focal length of 700mm and a focal ratio of f/11.7, which makes it roughly equivalent to the 60mm refractors sold by any number of astro vendors. I actually tested the PICO-6 side-by-side with London’s 60mm f/11.7 Meade refractor. The refractor threw up a brighter image – no shock there, since it’s unobstructed and has no mirrors to reduce light-throughput. But much to my surprise, the PICO-6 was a hair sharper: it could resolve fine details and split close doubles beyond the reach of the refractor. The differences weren’t dramatic, but they were there.
The PICO-6 comes with a dovetail bar and a brass compression ring in the visual back. Both required a bit of work. You can also see two of the three collimation screws in this photo.
I could not get a diagonal to seat in the visual back. After some investigation, I found that the brass compression ring could not fit neatly down into its groove. It had been poorly made, and had an extra flange of metal in two places that made it wider than the groove. It was the work of 5 minutes to grind down the extra width with my Dremel, but it’s still pretty disappointing. I don’t know how these things are made, but it seems unlikely to me that anyone could have seen this and not known that it was a problem.
Also, on the Kasai Trading “Dear Customers” page (here), under the heading “Quality Inspection” it says (courtesy of Google Translate):
Astronomical telescope of our handling is through the “Jisshi inspection” all by Kasai will be shipped to the customer. This is a test carried out by actually seen the night of stars, most practical-world, but the one that is adopted for performance is a test, it takes time and effort, also takes place on the night of good clear weather of seeing because it can not be accurate inspection unless, depending on the weather will give sometimes can not keep our promise of delivery date. Excuse me, please understand that effect.
That makes it sound like all of the scopes are star-tested before they go out to customers, but that clearly is not the case, because the scope I received was unusable until I fixed the visual back.
The dovetail bar is also a bit wonky. It’s a couple of millimeters narrower than the Vixen/Orion/Celestron standard, so it will fit into a standard dovetail slot, but you really have to trust the thumbscrew because it will be the only thing holding the scope into the mount. I solved this by putting the scope on a dovetail shoe for the pistol-grip ball head shown here – by design or coincidence, that shoe is a good fit for standard Vixen dovetails. With the help of that shoe, I was able to use the scope with my Universal Astronomics DwarfStar alt-az head. More on that soon.
Now, it may sound like I am down on this scope. I’m not. I wish the quality control was a little higher, but the problems were not unfixable. At least for me, with almost nine years of experience tinkering with telescopes – I can’t recommend this scope for anyone who isn’t prepared to do some work on it. And optically it’s okay. It arrived out of collimation, but with a little help from Polaris I was able to get it tuned up enough to catch Saturn’s Cassini Division and split Epsilon Lyrae cleanly into all four components at 117x. After the mechanical difficulties with the scope, that was a welcome surprise.
Then I flew with it, but that’s a story for the next post.
Last night the PVAA had the 60-inch telescope booked at Mt Wilson. It had been ages since I’d been up there – my only other trips up were in 2009 and 2010 (observing reports here and here). So it was very satisfying to be back. It is amazing to look back and realize that in 2010 I was only 3 years into what has now been almost 9 years of stargazing.
The last two times I went up, we didn’t have time for a tour of the grounds, so about all I saw were the parking area, the 60-inch dome, and a few odds and ends in the distance. This time we got a nice long tour from Geo Somoza – most of the rest of this post is a photographic tour of part of the observatory. We didn’t have time to go through the museum up there, or see the solar telescopes – guess I’ll just have to go back again to catch those (which is no bad thing!).
I rode up with Ron Hoekwater, Laura Jaoui, and Gary Thompson, who kindly drove us. We left Claremont early and got up there about 6:00, well in advance of the planned 6:30 start time for the tour. While we were chatting outside the gate, we saw something ominous: a tower of smoke going up from the mountains to the west. This would come back to haunt us.
Here’s the dome of the 100-inch Hooker telescope – world’s largest from 1917, when it eclipsed the 60-inch telescope on the same mountain, until 1948, when it was eclipsed in turn by the 200-inch Hale telescope on Palomar Mountain. It is a bit staggering to realize that from 1908 to 1993, when Keck 1 went online on Mauna Kea, the three consecutive world’s largest fully-functional telescopes were all within 92 miles of each other in southern California. (The 240-inch Soviet BTA-6 saw first light in 1976, but it suffered terrible thermal stability and seeing problems and never performed anywhere near its full potential.)
This bridge is nicknamed “Einstein’s bridge” because Einstein paused here for a famous photograph during a visit to Mt Wilson in 1931 – see that historical photograph here.
Here’s the scope itself, the same machine that Edwin Hubble and Milton Humason – a former mule-driver who worked his way up to master observer – used to chart the expansion of the universe. I was scheduled to go up and observe with the 100-inch last year, but I got very sick the day before and couldn’t make it. So that is still on the bucket list.
A view into the back of the mirror cell of the 100-inch telescope. The green champagne-bottle glass of the primary mirror is clearly visible. If you click through to the full-size version you may be able to see bubbles in the glass. The 14-inch-thick mirror had to be made in three separate ‘pours’ of molten glass, and bubbles from the first two pours were trapped by the layer above. The people at Mt Wilson were so concerned about the bubbles interrupting the figure of the mirror that at first they refused to work with it, but St Grobain Glassworks was unable to pour a better one and eventually George Ellery Hale ordered his people to grind and polish this mirror, which turned out to be fine at the optical surface after all.
In the old days, to observe visually with the 100-inch you had to go down a narrow hallway to a tiny room where light from the scope was bounced to the Coude focus. That was pretty unsatisfying so a few years ago the telescope was modified for more intimate visual observing. Now the primary mirror at the bottom of the scope bounces the light to a secondary up in the upper cage, thence to a tertiary at mid-tube which directs the light out to a quaternary mirror in the diagonal housing at the top of the black tubular assembly on the left of the scope in the above photo, thence down to a quinary mirror at the bottom of the black tube, then into the white refractor that is pointing down and to the right. A diagonal sitting nearby can be placed into the refractor to put the eyepiece into a convenient orientation when the scope is tilted.
The control board of the 100-inch, with at least three separate control systems lined up right to left in order of age. Most interesting is the old table on the right with the clock and the two periscopes. The periscopes allowed the telescope operator to see the telescope’s setting circles. Nowadays, the scope is controlled by the computers on the left.
Excited amateur astronomers lingering outside the dome of the 100-inch. We got to walk around on the walkway you can see on the outside of the dome. The entire dome rotates, walkway included. It’s a fearsome engine indeed.
On the left is one of the six domes of the CHARA array, I believe still the world’s longest-baseline optical interferometer. It has enough resolving power to image the discs of nearby stars. On the right is the 60-inch dome.
Geo shows us the concrete pier used during the speed-of-light experiments in the 1920s. More on those in a sec.
For decades in the late 1800s and early 1900s, Albert Michelson conducted a series of experiments to measure the speed of light. In a series of famous tests in the 1920s – almost two decades after Michelson earned his Nobel Prize – a beam of light was bounced from this pier on Mt Wilson to a mirror on Lookout Mountain, one of the foothills of Mt San Antonio, better known to locals as Mt Baldy – the mountain at whose base I live. The concrete pier on Lookout Mountain is still there and it is apparently an easy hike. It’s on my to-do list.
Sunset over LA. On the left, the marine layer of fog is moving in over the city. On the right, a tower of smoke is going up from a wildfire near Calabasas, about 40 miles to the south and west of Mt Wilson, and spreading out over the LA basin. For a while the smoke was going southeast from the fire, and it looked like it might miss us. But by the time it was getting dark, the wind had shifted and was carrying the smoke directly toward the observatory.
As darkness fell, we trooped into the dome of the 60-inch telescope.
Here are the controls for the dome’s shutter, which has to be opened for the telescope to see out, and closed again to protect the telescope during the daytime and in inclement conditions. The three light bulbs on the upper left of the console are original Edison bulbs – they have been working without ever being replaced since 1907 or so.
Our telescope operator, Christopher Burns, checks something on one of the computers in the control center, while beyond him Geo stands by the mercury tank in which the 60-inch telescope floats. Don’t worry, it’s fully sealed now. In the old days, it was open, and mercury would sometimes splash on the floor as the telescope rotated.
Our first target was Jupiter. As usual, the photo completely fails to do justice to the naked-eye view. The seeing was imperfect and I think the smoke from the fire might already have been affecting the views. The north and south equatorial and temperate belts were visible, and the Great Red Spot was prominent, but I could see little detail beyond that. I have seen much better on other visits, and indeed in much smaller scopes (see for example the two previous Mt Wilson observing reports linked at the top of this post). But I won’t complain too much – part of the joy of observing with the 60-inch is in the process, not the outcome.
After Jupiter we moved on to the globular cluster M3, and then the Sombrero Galaxy, M104. M3 was already looking a bit dim – certainly not as bright as it appeared in Ron’s 25-inch scope from RTMC last weekend – and about this time the smell of smoke became pronounced in the dome. We had a hurried look at M104, but it was just a dim smudge of light and I couldn’t even make out the dust lane.
After M104 we had to shut down early to protect the telescope. If ash from the fire was allowed to fall on the mirrors, it would combine with moisture in the air to produce acids which would eat away the coatings. In the photo above, Geo is shining a laser up through the optical train to check for ash on the mirrors.
It was a bummer to have to shut down early, but we had an awesome tour and it was fun to observe again with the 60-inch, even if only briefly. Geo and Chris were great hosts and everyone had a good time. We’ll get to reschedule our night on the scope, since we only got about an hour and a half of observing in, so the club’s investment is protected. It’s a shame about Mars, though – we won’t have another opposition this close for some time, and the planet will be noticeably more distant, smaller, and dimmer by next month already. Still, into every observing career a little rain – or ash – must fall, and I’ve been extremely fortunate. Two eclipses (2012, 2014), a Venus transit, and a Mercury transit in the last four years, and not one of them clouded out. Mars will be back, and I’ll be ready.