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Tuesday, April 24, 2012

Glassy Unveil

A few months ago, I posted about a weekend work day at the Mirror Lab which coincided with the casting of a second mirror for the Giant Magellan Telescope.  The first segment for the telescope is nearing completion in our polishing lab and our casting crew can certainly cast them a lot faster than we can polish them!  The casting schedule lasts about 3 months from start to finish, so the casting oven was opened about 10 days ago, and the crew has been working hard disassembling hardware from around our new pride and joy.




The first job in exposing the new mirror is the removal of the top and sides of the oven and stowing them out of the way.  That done, this last Thursday I caught them removing the inconel bands which wrap around the mold during the casting progress.  Yesterday they removed the hard refractory tub walls and scraped away the soft machined refractories to expose the outer edges of the glass blank.  So you can see if you blink, you can easily miss a step as the crew hustles to expose their handiwork. 

At left, staffers Bruce and Tom get a close look at the surface of the mirror.  You can see the hexagonal structure of the casting - here the glass entombs the mold hexagons, but soon the mold material will be removed to only leave lightweighting hollows in the mirror blank.  In the right photo you can see the mold cores go through the full thickness of the mirror leaving an inch thick layer of glass at the bottom and a couple inches of glass on top for the mirror surface.  You can also see the 36 meter radius of curvature on the top caused by the 4 rpm rotation of the oven while the glass was molten.  In the coming months a lifting fixture will be fastened to the face of the blank and it will be moved to the cleanout stand where the mold will be removed leaving a hollow structure leaving a "light weight" mirror that weighs a little under 20 tons.  Then we'll get it, likely about the start of next year to start the task of fabricating it into a fine jewel of a telescope mirror.  Stay tuned for updates!

Saturday, April 21, 2012

Backyard bird watching!

Dean is off to Kitt Peak for an Advanced Observing Program, but not before we checked my camera bag for anything he might need tonight.  Doing that reminded me that I hadn't done anything with my pictures lately, and couldn't really remember what I had photographed lately.  Sometimes you wind up with pictures that are better off deleted, sometimes you find little gems!
Back on March 28th I espied a Gambel's Quail roosting in a tree, behind our fence.  He wasn't being very quiet about his existence there, he was calling like mad - either for a mate, or warning the other quail in the area that "there's a bunch of cats over here!"  Either way, I had never seen one roost in a tree - I didn't even know they did that!  They aren't very big, not like a turkey roosting in a tree, but since they're ground birds I thought it was unusual.  Dean says that he's seen them do that before, not so unusual after all, and I have seen at least one more in our trees since then.
So, to read about our little friend, click here: Gambel's Quail  They have a very distinctive little call, nothing fancy mind you, but now that I know what they sound like I listen for them in the lot behind our house.  We haven't seen any chicks this year, but the best description of them is little gray cotton balls with fast moving feet.  Surely, there is a method to their madness, but it's hard to tell what that may be!

Wednesday, April 18, 2012

Bruce?!

Yes, the computer is back from the shop, backup files successfully loaded, and I'm slowly getting software reinstalled.  So mostly things are back in operation, though I still don't understand why it was necessary to reformat the disk...  Oh well, I'm glad things are back to "normal".

Years ago we had a groundhog that lived under the building adjacent to our place in Illinois.  We affectionately called him Bruce, and posted about him several times.  One of the groundhogs died, and another that took his place was the subject of a capture attempt.  In any case, we've been over a year since we've seen a groundhog near the place.









Well this last trip, Melinda caught a glimpse of him near his old haunt.  The next morning, we caught a blur of motion out the door, and sure enough, some version of Bruce slowly emerged from under our storage shed, turned and kissed a little angel statue we've got, and seemingly ignored us taking his picture through the glass of our kitchen door from a distance of 20 feet or so.  While we know that they can do some damage to structures, thus the attempt to capture the one in the camp, we'd love it if he took up residence under our shed.  It is always fun to have a friendly face around the place!

Thursday, April 12, 2012

Watching The World Fly By...

Just having returned from 8 days in Illinois, I feel the need to post, since the computer has been down (and is still in the shop).  But tonight I'm using Melinda's laptop and will post a few plane pics, since I've got the card from the camera.  Funny how you can be zipping along at 600 mph, yet the 3+ hours seem like 20!  So I try to entertain myself with what I see (the day's NY Times only gets you half way there), try to record it and explain what you see.

On the trip up to the Midwest about 10 days ago now, they had severe thunderstorms in the Dallas area the day before.  We were well north of that, but was shocked to see plentiful snow on the ground!  Of course, once we get more than a couple hundred miles from Tucson I tend to get lost, so I wasn't sure exactly where I was, but the enclosed pic, a 3-D shot of a volcano, I suspect was in northeastern New Mexico.  Much of that state is high enough it would explain why the snow was sticking around...  I've always wanted to visit this area, but it really isn't on the way to the Midwest from southern AZ, not that we've driven it lately.  But the cinder cones look interesting  The 3-D shot was taken by taking a photo pair a few seconds apart.  So the plane's motion of a mile or two gives a baseline to provide the appearance of depth.  As usual, cross your eyes slightly to fuse the two images to show depth.

Shortly afterwards it clouded up and the ground disappeared until we entered clear air over Iowa.  Again, not knowing where we were, I finally located us when we crossed the Mississippi about Dubuque.  We then crossed over Rockford, Illinois, the nuke power plant's cooling towers visible SW of town.  We were on course for me to take a picture of our house, easily found on the Fox River when we'd pass it.  But wouldn't you know, just before the Fox was spotted, the plane banked sharply to the south, and when we headed back east, we were literally right over our house as the city of St Charles, our base of operations while in Illinois, was nicely visible out our right side window.  Our place on the Fox is frequently on the approach to O'Hare, and our plane did the same - no pic-o-the-place that day!

On our return trip last night we took off right about sunset, and I thought there would be little chance for taking any images, but wasn't sure.  Again, we were on the right side, but unfortunately we passed well north of St Charles on the outbound flight.  But by the time we got to my ancestral home in Iowa, my birthplace Clinton, was nicely positioned.  Much of the layout was quite familiar, and had we passed over during the day, I likely could have spotted relative's homes!  As it was, in the growing dusk, the quarter second exposures came out pretty well.  Provided here is a wide view, and an annotated closeup view of the same image...  From the lock and dam to my Granddad's farm, it was all laid out in view.


A mere 25 miles to the west, the town of DeWitt was visible.  A little unexpected was a fire just south of town - interesting because that is where my brother Jim lives.  I called him this afternoon and asked about the fire - he said it was a farmer burning his field - sometimes done to help control certain pests.  It was only a mile or so from his place - one of several fires we saw across the state last night.  Just to the left of the cloud of smoke is the metropolis of Grand Mound (ran short of town names in olden days), where our farm was when I grew up. 


As it got darker, I put the camera away, but then saw something that perked my interest.  Looking at the wing from the rear, it appeared there was some sort of a mirage effect off the leading edge of the wing.  Of course, the curved leading edge should have provided a reflection of the sunset, but it seemed weird that there was a dark line before we got the twilight glow.  My suspicion is that air is highly compressed along the leading wing edge and under the right circumstances can refract light a little strangely as a result.  So I took some wide and narrow shots, varied exposures and show two of them here.  I don't yet know if it is weird or unusual, but it gives me something to do on a long trip...  I'll consult some experts, but in the meantime, if any of you have theories, let me know!

Wednesday, April 11, 2012

System(s) Recovery!

We've spent the last 8 days in the Midwest enjoying a spectacular Spring.  While there my computer (which I use for posting on the blog, as well as organizing images) decided it didn't want to run Windows anymore.  I managed to save a backup while in safe mode, but I've been unable to reload the sizable chunk of images after reformatting the disk.  So while getting the computer restored, and getting caught up on hours on my two jobs, it might be another week till we get a post - good thing we're well-rested!  Eventually we'll have a bunch to bring you up to speed...