Friday, December 19, 2014

Lost And Found!

I take a lot of photos, likely over 10K per year, especially with time lapses and stacking of astronomical images. Most are what I think would make good blog posts, and it is certainly easy to take lots of pictures these days without the cost of film or processing!  At the same time, I find that if I don't get them in the blog queue right away, they get lost under more recent images and get forgotten. 

While walking along the river the other day (we're still in Illinois), a set of IR images I took this summer came to mind.  In infrared wavelengths, water is a good absorber, looking mostly dark in images unless you get a reflection.  The above image shows the Wood effect clearly - very bright vegetation from the trees on the far bank.  But what came to my attention was the light streaks in the water at the bottom.  Turns out the Fox River is very shallow at this point, only about 25cm (10 inches).  What was coming into view was the river equivalent of seaweed or moss, growing in long strings.  Taking longer exposures, it took a couple shots for me to expose long enough for details, shown here at right and left.  It took about 10X the exposure to bring out the white-glow of the underwater plants.  In the shallows the local current carried the sinuous plants downstream, and getting a couple shots with different patterns was easy to do.  It made for interesting patterns, and it is also interesting to see how murkey the water looks due to the water absorbing the IR wavelengths.

Back in August our barrel cactus was in
full bloomin' mode.  While the buds were easy to catch, looking photogenic for several days before popping into flower, by the time I get back from work, they've been open all day and are well-worn from pollinators.  In any case, these pair of images were taken with a macro, with at least 6 frames taken at different focus settings to combine into the final focus-stacked images.  Clicking on the right image you can see how the stigma are wiped clear of pollen on the outward-facing side.

In October, my friend Bob Taylor invited me up for an observing session at the Mount Lemmon SkyCenter.  I'd posted many images, but had taken a series of sky exposures that for some reason weren't up to my standards.  However, as a result, one of the highlights of the all-night session, of the Gegenshein clearing the pre-dawn horizon didn't make it into the blog.  Shown here at left, the conical glow in the sky is not from the rising sun, but rather sunlight reflecting off dust from comets and asteroids in the plane of the solar system.  Following the ecliptic path, it shoots right up towards and engulfing Jupiter, the bright object at upper right.  Visible nearly all year long from a dark sky, it is especially visible in the northern hemisphere in the early Fall morning sky and the early Spring evening sky when the ecliptic makes a large angle to the horizon.  And since I don't like unlabeled star fields, I've included an annotated version at right, including the outline of Mount Graham at lower left, an antenna array at bottom center, and the red-lit antennae 5 miles distant at Mount Bigelow.

So I'm glad I re-discovered these images that hadn't appeared here before.  Certainly worthy of blog-inclusion!

Wednesday, December 17, 2014

Birthday Bootie!

So Melinda and I celebrated my birthday yesterday, which included a surprise or two - it deserves its own post rather than an addendum to the previous entry. We agreed to meet our friend Carolyn for brunch at the Colonial Café (Pumpkin Pancakes!). We had just sat down when our waitress informed us that the person who had been sitting on our table had just bought our meal with a $50 gift card! What a birthday present! This is now the second or third time a stranger has surprised us with picking up our tab, and we've "passed it forward" and done the same, anonymously, of course (more fun that way!). After telling our waitress it was my birthday, I got another $5 off card for the next visit, so we can likely eat again for free with the remnants - how cool is that!

Beloved Melinda, after stating she had to go out and find me a birthday present the evening before (we kid each other about swinging past the convenience store for a car-freshener gift), surprised me with gold astronomical cufflinks! I don't think I've got any dress shirts that take cufflinks, but she has agreed to sew some buttonholes in a couple of my long-sleeve t-shirts so I can wear them! The cutest story is that she bought them shortly after we met - the above-named Carolyn was having an estate sale, liquidating some of the antique collections she and Bob had acquired, and she had only these two left. Interestingly, they are my (Sagittarius) and her (Pisces) signs of the zodiac!  So she has hung on to them for 8 years to give them to me - that woman plans ahead!

We made it out to dinner last night at one of our favorite pizza places here - Giordano's!  Famous for their stuffed-crust pizza, we'd not been there since Summer, so was a birthday-worthy event. We got what has been our increasingly favorite flavor, pepperoni, sausage and mushroom, both of us managing two pieces, assuring I'd have leftovers in a couple nights when Melinda and her nurse buddies have dinner together. It was pretty darn tasty - just what the occasion warranted. We even got home in time to relax in front of Rachel Maddow, as Melinda refers to her, "Dean's lesbian girlfriend", since I seldom miss her daily show. Anyway, a great birthday, now committed to the blog for all time...

Tuesday, December 16, 2014

Birthday Boi!

Sometimes during our between-holiday visit to the Midwest (nice to miss both Thanksgiving and Christmas holiday travel madness), we overlap on my birthday, which is today!  Sixty One times around the ole' sun.  To yank people's chain and provide a teachable moment, I used to provide it in Saturnian years.  Fifteen years ago that made me about 1.5 Saturnian years.  Of course, not having kept up with the math, I missed my 2nd Saturnian birthday, which would have been last year!

Anyway, we also spend a day in Iowa visiting my family each visit, so Sunday the Ketelsen kids got together at a popular pizza buffet place - Pizza Ranch!  We like it because we can also schedule a private room and they don't rush us out when we hang out a couple hours visiting.  Interestingly, Sunday was also my mother's birthday.  She would have been 81 (died in '88 at the age of 54...).  But all the brothers and sisters were there, save baby Sheri, now living in Texas.  My niece Marsha now manages a local bakery and provided an astronomical-themed cake - a great job!  That is her on the right with her nearly senior Uncle Dean.

Not wanting to blow the budget on candles, nor set off the fire alarm or sprinklers, instead of 61 candles, we grouped 6 and 1 candles before lighting to represent the correct number in earth years. I still had the lung power to extinguish them - in fact, Alivia didn't know what she was in for, using her hands to fend off the smoke and sparks from my huff and puff! Great nieces Mya and Alivia later joined Great-Uncle Dean for a portrait at right.

It was nice to catch up with everyone's lives.  At left is nephew Brennan - recently passed his nurses board exam and is now gainfully employed in Davenport in an ICU ward.  Wearing the Schwarzenegger shirt, I had him pop out a bicep, semi-emulating the pose on the shirt.

Whenever you get more than 2 of the brothers and sisters together, there are group portraits going on and for a special occasion like this one, lots of photos were taken.  At right we are gathered around Aunt Velma. In recent years we used to gather out at the farm where she and Uncle Arlo lived. Arlo passed 16 years ago, and Velma finally moved to town a couple years ago. Just this last fall, an illness put her into an assisted-living facility, where she seems content to live. Melinda and I were able to check her out to come join us for dinner and a bit of celebration, and of course, the group picture. Brothers Jim and Brian join me in the back, and Linda and Kathy in the front on either side of Velma.

It was a fun family time, and I have leftover cake for my actual birthday today.  Nothing big planned, just quiet time with my sweetie, perhaps dinner out, and cake in front of Rachel Maddow - what could be better?!

Monday, December 15, 2014

Another Classroom Session From Our Trip!

My bloggin' buddy Ken Spencer and I both love to watch the country slide past our windows while flying.  We're both amazed more people don't watch - on our trip last week to the Midwest, most even had their shades down!  Besides illustrations of fluid dynamics, shown in the last post, it was a classroom in other effects, even though it was cloudy for most of the trip. 

On a trip just over a year ago, I caught my first "subsun", documented in another travel post about this time last year. Les Cowley, who runs the "Optics Picture of the Day", a great website of atmospheric phenomenon, even devoted a page to the image last Summer!  While evidently pretty common, subsuns appear low with the sun high in the sky, so are likely normally unobserved.  This trip, about an hour before our arrival in Chicago, likely somewhere near Kansas City if we kept to our normal route, I spotted one, this time without "subsun-dogs".  It appeared as a very good, though dimmed, image of the sun without much scatter to blur the suns reflection from aligned flat ice crystals.  From my first image to the last, 6 frames were obtained in 90 seconds - the extent of the subsun data collection this trip.

The clouds were dense and constant from central New Mexico to our arrival in O'Hare, and as we banked for final approach, were still above the cloud deck.  I hoped-for and watched, but didn't see the Willis Tower (second-tallest building in the country) poking above the clouds.  We usually have a fine view of the skyline during that final turn.

This time, however, we had an even more interesting view. Now headed west towards O'Hare, and us on the right side of the plane, we were treated to seeing our shadow. If you had been looking, you would have seen a shadow of the plane, yes, but something extra - circular bands - a glory! The photo at left was taken with the camera at full zoom of 85mm focal length, with minimal adjustments of brightness, contrast, and a slight boost of color saturation. I'll let you go to Les Cowley's page about glories to learn more rather than me wave my arms here to explain. Make sure you look at the several pages of illustrations and explanations and other examples. Now what is really cool is that you can infer the water drop size from the diameter of the glory! The subtended diameter is inversely proportional to the droplet diameter. For grins, I took the full-frame image at left, and cranked the color saturation, and made some measurements, shown at right. The sensor size is 24mm long, and the number I've carried in my head from college is that 1 degree for any lens is .01744 X the focal length, in this case, 1.48mm.  Knowing the scale, the red rim of the first ring is 6.5 degrees.  With Les' equation from one of those pages, the droplet size works out to 19 microns - pretty cool!

Two minutes later, we approached the cloud deck and I shot again, this time with the lens set much wider to get in the whole shadow.   Note that the glory indicates where we were sitting, between the wing and the rear-mounted engines near the back of the plane.  As Les points out, every observer sees their own personal glory - the one the pilot sees would be centered on the front tip of the plane...  The calculation of the droplet size should be independent of the lens focal length, so I repeated the calculations on another image with the saturation cranked for this image's 33mm focal length.  This time I got 21 micron diameter droplets, a difference of 10% from the first calculation - good enough for me!  Whether the difference indicates a real change in droplet size, or an uncertainty in the or measurement remains to be seen...

The last science demonstration occurred minutes later as we descended below the clouds.  I saw what looked like a flash of "white smoke", but was actually water vapor condensing in the pressure difference caused by the turbulence between the flaps and ailerons.  The flaps, fully extended, with the ailerons in their neutral position, caused enough of a density change to cause moisture to condense into a stream (arrowed at left).  Again, the world is a science laboratory with much to observe if you only look!

Saturday, December 13, 2014

Lessons in Fluid Dynamics!

The other day we again transited the country, flying to Chicago to visit family and friends at "Ketelsen East". Another uneventful trip, with my nose pressed against the window. I saw something today on the Interweb that prompted me to do this post - more on that in a minute.

As sort of an introduction, I've always enjoyed the views from mountaintops. The reasons observatories are built there is that many detrimental effects occur at lower levels. One of the first things you notice, particularly at this time of year when inversion layers form and trap haze and pollutants at lower levels, is that the mountains poke above these layers into clearer air. It wasn't 5 minutes after takeoff that the Whetstone Mountains short of Benson (at left)were seen sticking above the haze trapped from there down to Sierra Vista and the Huachuca Mountains at distant center. In this case, and likely all the others shown here, warm air above traps cooler air (and particulates) near the ground.

Not far across the border in New Mexico, even before we had reached our cruising altitude, I spotted an interesting cloud formation far below us.  Checking times and Google Maps, it appears to be ground-hugging clouds between the Pinos Altos mountains at bottom center and the Black Range at upper left.  Here again, the cooler, moister air appears to be filling the canyons and valleys in the mountains.  It seems amazing that giant cloud formations miles long can form these serpentine shapes following the terrain of the mountains.  It demonstrates the fluid properties of air and the material it carries along.  The right image is a closer view of the left edge of the left frame as we passed over.

I've seen some spectacular time-lapses demonstrating the fluid properties of clouds - "Vancouver City" comes to mind, as does "Island in the Sky".  If you have a few minutes, you REALLY should watch both, in HD, fullscreen, with sound! 

Anyway, all this is a lead-in to the cloud inversion observed at the Grand Canyon 2 days ago (Thursday).  A time-lapse, taken by Michael Quinn for the NPS, compressed 15 minutes of images into a 1 minute video.  Perhaps it is something so familiar to us regulars from the Grand Canyon Star Party looking so unusual that catches our eye, but the fluid properties of the clouds looks so much like waves rushing against a rocky beach. I'm not sure where this was taken, but I've seen some of his other images taken from Mather Point, so it might well have been taken there looking SW towards Yavapai Point, a couple hundred yards from where we set up in June.   No sound on this one, but very fun.  Enjoy!

Up to Date on Construction!

In the last post, you saw the walls and siding of the back yard observatory going up in a day's work.  It was a few days later till we got back to it with John's schedule, and my task was to work out the final pivot dimensions for the roof. I made another larger-scale model and found there were so many variables that it was tough to finalize.  Generally, some notes are shown at left.  The outer pivots attach near the roof Center of Gravity (CG), and will be counterweighted to assist in lifting the roof off the walls as well as starting the roof closed.  The inner struts, attached to the center roof pivots, are mostly for guiding the roof, perhaps partially counterweighted.   As far as the roof pivots were concerned, they could be attached, so after an aborted attempt to install the door, construction resumed on 5 December.

The original door installation was complicated by the 6 foot wall height.  That meant a good foot was chopped off the door, including the lower hinge.  That reduced the stability of the door to the point that John had difficulty getting it to hang properly.  After an hour's effort, without the right tools with him and with me still uncertain about pivot locations, he left to go paint houses to return another day.  This day with the right tools, he remounted the previously sawn-off hinge and it then behaved normally in its installation.  Now, with the gentlest of swings, it closes and latches nicely!

After that old business, it was on to
installing the pivots on the roof sections.  I had made the pivots out of 1" diameter solid steel shafts, welded into 3" angle iron to facilitate attachment to wooden frame or welded to the roof frame.  There is also a tapped hole in the shaft to hold on the expected struts that will be mounted.  I marked out where I wanted them and John made good use of his welder to attach them permanently.  At left, he welds one at the center of the roof section that faces outwards (another already mounted above his helmet), and at right he welds one on the inside of the roof section.

Note in the previous image that the inner pivots are not well supported, welded only on the inside 2" of their 6" length on the roof tubing.  I had gotten some 2X3" steel tubing to reinforce them, and at left John again uses his handy grinder with the cutting blade to chop them to 6" lengths to weld on for reinforcing.  In addition, I fabricated some hefty hold-down brackets from 3.5" heavy-duty angle iron.  Particularly with a mostly counterweighted roof, I didn't want roof sections flying off in inclement weather!  With these brackets welded on (shown at right), with the six 3/4" bolts holding the roof on to the observatory frame, it won't be going anywhere!

Finally it was time for a roof!  Using
galvanized steel roofing, after deciding on how long to overhang, he chopped them off (again that grinder/cutting wheel) to the right length before hoisting them to the roof frame for attachment.  Starting on the top, on one end, he went along and fastened them down with self-tapping screws into the metal frame.  There is a little washer with rubber grommet that seals out weather from future storms... 

As you can imagine, with pretty large sections, it went up pretty fast, with a couple ribs overlap between sections.  Battery-powered tools are wonderful for working over a large surface without running an electrical line.  The hex-head socket is also great to get in the screws without stripping-out the normal Phillips head screws...  Before I knew it, he had all the roof sections on, and attached a center span to seal against weather (attached only on one side for roof removal). 

Since this was our last work day until after the holidays, I had asked him for a "bill-to-date".  Interestingly, his labor was pretty much exactly the same as the materials used!  I'll likely provide a final cost when we're finished.  The only work remaining is electrical (which I'll likely do with friend's volunteer effort), finish sealing the roof with siding, and building trim.  I'm sure he wants to see how well my plan for the removable roof works, which I'll attack over the holiday as well.  Then it will be finished 'cept for the telescope part - a whole 'nother story. 

After my van collision and the anticipated totaling-payoff, I've moved all the astro and camping stuff into the now-weathertight observatory.  Lots of room to spare, so there was more room in there than it seemed!

Thursday, December 11, 2014

Update on the Back Yard!

When I last did an update on the back yard observatory, I had hired a building contractor, John Vermette, who came in and had a concrete pad poured 8 days after first meeting him. Since then, it seems like progress has been made at the speed of light, certainly orders of magnitude (factors of 10) faster than if I had tried to do it myself! I don't want to bore you with all the details, but at the same time, I think it might be valuable to others to see how this one has been done.

After pouring the concrete pad on 19 November (a Wednesday), I was to keep it watered down to prevent premature drying for a few days, and at the same time, keep off of it while it cured. By the weekend, it was at nearly full-strength, and I wanted to hoist the mount in place, as I didn't think I wanted to try it through a doorway. With John Davis' assistance and a borrowed engine hoist from work, it was done in a flash. At left, I had wrestled it in place, and at right, the job done, Mr. Davis gives it a once-over...

The next day, a Monday, John Vermette was there ready to work!  I got to help out as assistant so he didn't have to hire another helper.  While he had the expertise, and knew what had to be done, I learned and made the tasks a little easier for him...  For a small building this size (10X10 feet), you could likely do it yourself, but it goes easier and more quickly with two, and unskilled help like me was perfect for this application!

After ripping out the forms for the now-hardened concrete, he set to work to put up the walls.  I didn't have a chance to take lots of pictures, but in two hours, it went from a stack of lumber to recognized upright 6-foot tall walls.  Of course, the walls are firmly fastened to the slab with the j-bolts sunk into the concrete.  While we don't get tornados here, we get dust devils and huge gusts from monsoon storms, so this building isn't going anywhere without taking the slab with it!

Another two hours and the siding was on!  Shown here is a view through the only entrance now, the doorway - a two-frame mosaic.  It was amazing how much more sturdy the building became by adding the skin of the wood siding.  And with this all going up in 4 hours, it was amazing to get the feel of its appearance...

Two days later, John was back to work on the roof.  In his normal roll-off observatory construction, the roof is one piece.  I wanted to avoid the footprint of the additional area of the rolled-back roof support, and have a fold-down roof.  So his roof construction was a 2-piece and will split down the center.  At left he cuts the 13 gauge steel tubing with a grinder and cutting blade, and at right is welding it in place atop the wall with his MIG (Metal Inert Gas) welder.  With his use of magnetic clamps and his frequent welding, I had more chance to take photos during this stage.  His layout of both the walls and roof are quite accurate - he kept a square in his pocket for checking EVERYTHING, and his level was similarly often used in the wall layout.

The layout and welding similarly went
quickly on the roof sections too.  Again, less than 4 hours from start to finish.  At left is another welding shot, and at right is the finished product showing the two roof sections, split in the middle.  The metal frame helps keep the roof sections light weight - definitely needed for this fold-down design, but also used in his roll-off for its strength and rigidity.  I think he also enjoys the variety of metal/welding incorporated into his carpentry.  A little variety in the tasks always makes the job more interesting.

I didn't want to make this post too long, so will have another entry upcoming on further progress - that one will bring us up to date on construction.