No, I'm not talking about my every 2 month haircut and beard trim at Supercuts, but rather, the feral cat living out front that we've been affectionately calling Scruffy for nearly a year. We've blogged about him before, but yesterday was his "special" day, where he got to meet our vet, Dr. Kayomee Darowalla!
Scruffy is a beautiful cat, but suffered a number of obvious ailments. When he first visited a year ago, he was all skin and bones, but has bulked up a little with regular feeding. He was just covered with mats, in obvious pain, moving like a much older animal with arthritis. There were also some skin lesions and scabs - he was just pitiful! So the plan was to get him fixed - we weren't quite sure of his sex - neighbors down the street thought he was associated with a litter of kittens, so even at the last moment, there was some thought of a Scruffette. Any touching of the body south of the waist (lifting of tail) brought hissing and a whirr of claws, so the gender remained a mystery. We also had to have him tested for general health, communicable diseases, etc so there would be no risk to our other cats.
He showed up Monday afternoon for some food, and with a Tuesday surgery appointment already made (he missed one made 2 weeks earlier), I wrapped him in a towel and quarantined him in Jason's bathroom overnight. He seemed to do fine and was quiet on the trip to the vet yesterday morning.
A couple hours later the vet called - Scruffy was indeed a boy and was now neutered. They shaved off the mats while he was out. The skin lesions were caused by the abundance of fleas and bites he carried, and he also had ear mites, and 2 broken canine teeth that required Dr Darowalla to dig out the roots. With vaccinations and blood work, the total was $421.32 - and that with my 30% bulk-rate discount!
Perhaps the worst news is that he tested positive for FIV, the equivalent of HIV in humans. Our original intent was to not risk our existing cat population, and, in fact, the vet had already notified the animal shelter they run, in case we wouldn't be taking him home. After consultation with Dr Darowalla (who also has a FIV+ cat with 2 that are not, and in fact, Vicki and I had an FIV+ cat for many years), she convinced us that the risk is minimal, and that if introduced slowly and safely, everyone will be fine. She described using a dog crate to effectively keep him quarantined in the living room for days or weeks, so that everyone gets used to him. That way there won't be any biting and saliva/blood exchange, which is the only way to transmit the virus. She even lent us the crate, so when he recovers from the surgery a little more, he will be moved out of the bathroom into the living room.
He is a good patient - mostly content to lie down behind the toilet in the hall bathroom. He devours canned food, so rather than struggle to give him his 3 meds (pain, anti-inflammatories and antibiotics), we just put it in a little canned food and it is gone in 10 seconds! He'll look a little funny for a few months, but as his hair grows back, I'm pretty sure he'll get used to life here in the "cat house" and will do just fine!
We're glad to see you here! Come and share our daily lives with us, we welcome your company and your comments. We hope there is something here for everyone!
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Thursday, May 28, 2009
Tuesday, May 26, 2009
RTMC Wrapup!
The Riverside Telescope Makers Conference (RTMC) is an annual gathering of amateur telescope makers, as well as astronomy vendors and astronomy nuts of all sort. Always held over Memorial Day Weekend, it started in 1969, so this was the 41st meeting. I've been a regular since '87, and except when my mom died in '88, have never missed a gathering since.
It used to be THE west coast gathering for those interested in telescope making, or do-it-yourself astronomy. In recent years, however, the telescope making has fallen off with the ready availability of inexpensive imported optics. While 10 years ago there might have been up to 40 entries in the competition, this year there were 13, with 5 merit awards given out.
There is no lack of vendors, however! For them, having up to 2,000 enthusiasts (1,100 registered this year) attending over the weekend is a great way to showcase their new products. While I didn't recognise any new vendors other than Lunt Optical Systems (solar telescopes), the standard big vendors like Celestron, Meade, Tele-Vue and many others were doing brisk business.
I got my wish by the appearance of Olivier Thizy, a promoter of spectroscopy, who brought a set of instruments to show the solar spectrum to passers-by. He had a new fiber-fed echelle spectrograph that he allowed me to mount my new IR-modified camera to find it's wavelength limits. Shown here are Melinda checking out the solar spectrum in a smaller spectrograph, and the resultant echelle spectrum with the IR camera. Normally, the visible spectrum would run across the bottom of the image, but in this one, the red part of the spectrum noted the end of the visible range, and the longer IR wavelengths increase upwards. Note the blue appearance of the IR limit on top - it shows the blue pixels in the camera have an "IR leak" that tint deeper IR colors blue. Most visible in the spectral bands are dark lines that I think are due to telluric bands from the earth's atmosphere.
Likely the highlight of the conference is the swap meet. Over the years, I've seen most anything astronomical for sale or swap. Since we were staying in town and were up relatively late doing some observing Friday night, we were couple hours late and missed the big crowds and stunning deals, but were still impressed. As an optician, the highlight for me was a nice mirror blank for sale, shown here with owner Jerry. It is purported to be a spare from one of the Landsat programs, and is a fused quartz eggcrate fusing - two sheets with a thin web structure, making it lightweight and stiff, slumped to about F/2. Being fused quartz, it is low-expansion and is little affected by temperature changes. I couldn't resist, and after chatting with Jerry, agreed on a good deal. I see an 18" Cassegrain telescope in my future! Another spectacular table, was of the stony-iron meteor section hoisted here with abundant olivine crystals, looking like stained glass. It was easy to resist this piece with it's $15,000 price tag!
The real highlight of the conference for me, though, is always the one time a year to catch up with similar-minded friends I only see once a year at this event. You can hardly take a few steps before seeing someone else to chat with. It is amazing the contacts you can make over the years, from well-known observers at Palomar like Jean Mueller, to optical and aerospace engineers like Dave Radosevich, and Jack Eastman, shown here with friend Valerie Goff. Of course, Jack not only looks like a character, but is indeed one! He was involved with optical manufacture early on - from Celestron in the early days, to Lockheed -Martin, where he recently retired.
And while revisiting these friends every year is the highlight for me, organizers are slowly changing the event. With interest in telescope making waning, they are working to change it to an observing event. While normally always held on the holiday weekend no matter the moon phase, next year it is moving up to be held on the dark-of-the-moon weekend for dark sky observers. It remains to be seen if this will hold on to attendees, or if registration will continue to slide. For me personally, observing conditions are much better here in Arizona, and I wouldn't make the trip just to observe. If my acquaintances stop coming, I'll likely do the same...
There were an abundance of great talks this year. Highlights for me were mostly historical in nature. On Saturday Tom Johnson, the originator of Celestron talked about the early days of the company. He is shown at left, and also appeared in the ad copy on the right from 40+ years ago. On Sunday morning, there was an amazing talk by Scott Kardell on the construction of the Hale 200" telescope. What was amazing to me, the jaded, reasonably well-read astronomer, is that I hadn't seen any of the dozens of archival images he showed in his talk. Scott also runs a Palomar-themed blog. And of course, another highlight was the Bob Goff lecture, started by his widow Valerie and me after Bob's passing 7+ years ago. This 7th lecture was given by Robert Sigler on the topic of "Glass-Liquid Apochromats", using liquids with unusual optical properties to improve telescope performance with normal or inexpensive glass. With high performance apos costing upwards of tens of thousands of dollars, designs using liquids can provide high performance with reasonable cost...
RTMC has always been a part of my Memorial Day Weekend, but it remains to be seen if that relationship will continue into the future!
It used to be THE west coast gathering for those interested in telescope making, or do-it-yourself astronomy. In recent years, however, the telescope making has fallen off with the ready availability of inexpensive imported optics. While 10 years ago there might have been up to 40 entries in the competition, this year there were 13, with 5 merit awards given out.
There is no lack of vendors, however! For them, having up to 2,000 enthusiasts (1,100 registered this year) attending over the weekend is a great way to showcase their new products. While I didn't recognise any new vendors other than Lunt Optical Systems (solar telescopes), the standard big vendors like Celestron, Meade, Tele-Vue and many others were doing brisk business.
I got my wish by the appearance of Olivier Thizy, a promoter of spectroscopy, who brought a set of instruments to show the solar spectrum to passers-by. He had a new fiber-fed echelle spectrograph that he allowed me to mount my new IR-modified camera to find it's wavelength limits. Shown here are Melinda checking out the solar spectrum in a smaller spectrograph, and the resultant echelle spectrum with the IR camera. Normally, the visible spectrum would run across the bottom of the image, but in this one, the red part of the spectrum noted the end of the visible range, and the longer IR wavelengths increase upwards. Note the blue appearance of the IR limit on top - it shows the blue pixels in the camera have an "IR leak" that tint deeper IR colors blue. Most visible in the spectral bands are dark lines that I think are due to telluric bands from the earth's atmosphere.
Likely the highlight of the conference is the swap meet. Over the years, I've seen most anything astronomical for sale or swap. Since we were staying in town and were up relatively late doing some observing Friday night, we were couple hours late and missed the big crowds and stunning deals, but were still impressed. As an optician, the highlight for me was a nice mirror blank for sale, shown here with owner Jerry. It is purported to be a spare from one of the Landsat programs, and is a fused quartz eggcrate fusing - two sheets with a thin web structure, making it lightweight and stiff, slumped to about F/2. Being fused quartz, it is low-expansion and is little affected by temperature changes. I couldn't resist, and after chatting with Jerry, agreed on a good deal. I see an 18" Cassegrain telescope in my future! Another spectacular table, was of the stony-iron meteor section hoisted here with abundant olivine crystals, looking like stained glass. It was easy to resist this piece with it's $15,000 price tag!
The real highlight of the conference for me, though, is always the one time a year to catch up with similar-minded friends I only see once a year at this event. You can hardly take a few steps before seeing someone else to chat with. It is amazing the contacts you can make over the years, from well-known observers at Palomar like Jean Mueller, to optical and aerospace engineers like Dave Radosevich, and Jack Eastman, shown here with friend Valerie Goff. Of course, Jack not only looks like a character, but is indeed one! He was involved with optical manufacture early on - from Celestron in the early days, to Lockheed -Martin, where he recently retired.
And while revisiting these friends every year is the highlight for me, organizers are slowly changing the event. With interest in telescope making waning, they are working to change it to an observing event. While normally always held on the holiday weekend no matter the moon phase, next year it is moving up to be held on the dark-of-the-moon weekend for dark sky observers. It remains to be seen if this will hold on to attendees, or if registration will continue to slide. For me personally, observing conditions are much better here in Arizona, and I wouldn't make the trip just to observe. If my acquaintances stop coming, I'll likely do the same...
There were an abundance of great talks this year. Highlights for me were mostly historical in nature. On Saturday Tom Johnson, the originator of Celestron talked about the early days of the company. He is shown at left, and also appeared in the ad copy on the right from 40+ years ago. On Sunday morning, there was an amazing talk by Scott Kardell on the construction of the Hale 200" telescope. What was amazing to me, the jaded, reasonably well-read astronomer, is that I hadn't seen any of the dozens of archival images he showed in his talk. Scott also runs a Palomar-themed blog. And of course, another highlight was the Bob Goff lecture, started by his widow Valerie and me after Bob's passing 7+ years ago. This 7th lecture was given by Robert Sigler on the topic of "Glass-Liquid Apochromats", using liquids with unusual optical properties to improve telescope performance with normal or inexpensive glass. With high performance apos costing upwards of tens of thousands of dollars, designs using liquids can provide high performance with reasonable cost...
RTMC has always been a part of my Memorial Day Weekend, but it remains to be seen if that relationship will continue into the future!
Saturday, May 23, 2009
Stay tuned!
While Dean has been the primary blogger lately, I assure you - I'm still around! We're still at RTMC in California, and will make our trek home (across the Mojave Desert) tomorrow. I promise to have pictures from the trip home - as Dean has purchased a new camera for me for an anniversary present! This has been a great, fun, trip -- clouded only slightly by the bit of a cold that I've started with recently. So, stay tuned for our update and pictures when we return home!
Greetings From Sunny California!
We made it safely to California Wednesday afternoon, though our hotel in San Diego didn't provide Internet access. This morning we left the seaside and headed up to the mountains near Big Bear for the Riverside Telescope Makers Conference. Rather than the traditional camping, we are staying at Motel 6, so finally feel like we're in touch with the world again with e-mail and the beloved Blog!
San Diego and the Beach were great! We stayed in one of the regular haunts of Vicki and mine from years ago - Diamond Head Inn (where Diamond Street meets the Pacific Ocean). The view on the left is literally about 30 yards from the hotel, and taken a few minutes after we arrived. Melinda was just coming off shift when we left Tucson, so was very short on sleep, but the changing vistas of California (which she has never visited) kept her awake most of the trip. We hit the beach by mid-morning Thursday, and with lots of sun, we both resembled lobsters by the end of the day, even with the floppy hats we wore. Melinda was expecting to do some swimming, but didn't realize the water off CA was about 15 degrees colder than the Caribbean waters she was used to. She allowed it to get up to her knees, but that was enough. The sounds and smells of surf was great, though.
It took about 3 hours from beach to Big Bear and the conference. Crowds seem smaller than previous years, but from the moment we arrived we saw lots of friends from past years. Melinda was afraid she wouldn't know anyone, but within 20 minutes saw a number of people she knew from Tucson. You can tell she is well on her way to becoming an astronomer - she enjoyed the vendor tables full of telescope gear more than I did! As darkness grew, I took a few snapshots of Alan Guthmiller preparing his 20" telescope for the evening observing. With fewer vendors, the "telescope Field" was again available for telescopes, but there were much fewer of them than in the past. Perhaps tomorrow once the weekend arrives.
The highlight, perhaps, of the evening was a brilliant "Iridium Flare". These are reflections of the sun off of an antenna on the Iridium spacecraft. If you are on the right path on the earth, it directly reflects the sun to you and it can become many times the brightness of Venus. Tonight's was as bright as they can get, about -8 magnitude. My time exposure caught the flash as it passed through the constellation Corona Borealis (Northern Crown).
The conference starts in earnest tomorrow - some talks that look very good, and of course, the swap meet starts at 8am, and more observing tomorrow night, so looks to be a full day. More later!
San Diego and the Beach were great! We stayed in one of the regular haunts of Vicki and mine from years ago - Diamond Head Inn (where Diamond Street meets the Pacific Ocean). The view on the left is literally about 30 yards from the hotel, and taken a few minutes after we arrived. Melinda was just coming off shift when we left Tucson, so was very short on sleep, but the changing vistas of California (which she has never visited) kept her awake most of the trip. We hit the beach by mid-morning Thursday, and with lots of sun, we both resembled lobsters by the end of the day, even with the floppy hats we wore. Melinda was expecting to do some swimming, but didn't realize the water off CA was about 15 degrees colder than the Caribbean waters she was used to. She allowed it to get up to her knees, but that was enough. The sounds and smells of surf was great, though.
It took about 3 hours from beach to Big Bear and the conference. Crowds seem smaller than previous years, but from the moment we arrived we saw lots of friends from past years. Melinda was afraid she wouldn't know anyone, but within 20 minutes saw a number of people she knew from Tucson. You can tell she is well on her way to becoming an astronomer - she enjoyed the vendor tables full of telescope gear more than I did! As darkness grew, I took a few snapshots of Alan Guthmiller preparing his 20" telescope for the evening observing. With fewer vendors, the "telescope Field" was again available for telescopes, but there were much fewer of them than in the past. Perhaps tomorrow once the weekend arrives.
The highlight, perhaps, of the evening was a brilliant "Iridium Flare". These are reflections of the sun off of an antenna on the Iridium spacecraft. If you are on the right path on the earth, it directly reflects the sun to you and it can become many times the brightness of Venus. Tonight's was as bright as they can get, about -8 magnitude. My time exposure caught the flash as it passed through the constellation Corona Borealis (Northern Crown).
The conference starts in earnest tomorrow - some talks that look very good, and of course, the swap meet starts at 8am, and more observing tomorrow night, so looks to be a full day. More later!
Tuesday, May 19, 2009
Amazing Work Progress
The maniacs in casting at the Mirror Lab are making tremendous progress on the new mold for the 6.5 meter Mexican project. I just posted on their start on Friday and in the 2 work days since then, they have installed over 70 cores per day and are already over 15% finished! As a reminder, the left image shows the 20-some cores they installed on Thursday (they work 4-10 hour days, so didn't work Friday). Today's image is shown on the right. In talking to the crew, they are averaging about 10 cores per hour. At that rate, they should be done in a couple weeks - unheard of!
As I mentioned on the Friday post, they need the hollow cores left open to ream out the crosspin holes, and glue in the pins as the new cores are set into place. In the closeup at left, you can see the open holes facing the camera where the crosspins will be installed, and in the gaps between the cores, you can see the pins that join one core to it's neighbors and increase the mold's overall rigidity. Once a core is pinned to all it's neighbors, they can glue in the core top. The 3 dabs of blue coloring per top is where they drill and insert ceramic pins to mechanically join the core body to it's top. It is very similar to cabinet work where dowel pins are drilled and glued into place to strengthen joints and bond lines. The blue goo (affectionately called "Smurf Glue") is equivalent to spackling's filling of nail holes, and is used to fill in the gap where the pin is located. Damon is going over each core top and filling in each of the gaps.
Meanwhile, over on "my" side of the Lab, where we grind and polish the mirrors, there is no lack of activity. A snapshot of the Polishing Lab shows the Giant Magellan Telescope (GMT) pulled under the test tower for a lasertracker measurement. Since we are still in fine grinding (9 micron loose abrasive), the mirror is not yet polished (though at near-grazing angles, you can start to see the lab lights reflected in the surface) so a lasertracker (distance-measuring theodolite) measuring the surface height of a corner cube has been utilized to map out the surface and guide the figuring operation (improving the surface quality). In the background, the Large Synoptic Survey Telescope (LSST) can be seen on the Large Optical Generator machine in the background. Work has been proceeding on the backplate, and loose-abrasive grinding is about to start. Big glass??? Lots of it around here!
As I mentioned on the Friday post, they need the hollow cores left open to ream out the crosspin holes, and glue in the pins as the new cores are set into place. In the closeup at left, you can see the open holes facing the camera where the crosspins will be installed, and in the gaps between the cores, you can see the pins that join one core to it's neighbors and increase the mold's overall rigidity. Once a core is pinned to all it's neighbors, they can glue in the core top. The 3 dabs of blue coloring per top is where they drill and insert ceramic pins to mechanically join the core body to it's top. It is very similar to cabinet work where dowel pins are drilled and glued into place to strengthen joints and bond lines. The blue goo (affectionately called "Smurf Glue") is equivalent to spackling's filling of nail holes, and is used to fill in the gap where the pin is located. Damon is going over each core top and filling in each of the gaps.
Meanwhile, over on "my" side of the Lab, where we grind and polish the mirrors, there is no lack of activity. A snapshot of the Polishing Lab shows the Giant Magellan Telescope (GMT) pulled under the test tower for a lasertracker measurement. Since we are still in fine grinding (9 micron loose abrasive), the mirror is not yet polished (though at near-grazing angles, you can start to see the lab lights reflected in the surface) so a lasertracker (distance-measuring theodolite) measuring the surface height of a corner cube has been utilized to map out the surface and guide the figuring operation (improving the surface quality). In the background, the Large Synoptic Survey Telescope (LSST) can be seen on the Large Optical Generator machine in the background. Work has been proceeding on the backplate, and loose-abrasive grinding is about to start. Big glass??? Lots of it around here!
Monday, May 18, 2009
Kitt Peak and Infrared Fun!
I've been having fun with my modified digital Canon 20D - the normal infrared blocking filter was replaced with a infrared passing filter giving some new effects when looking at normal objects. I was looking forward to our Saturday trip to Kitt Peak National Observatory to try some new perspectives. The "Wood's Effect" of IR photography makes live foliage look white, and the blue sky and bodies of water dark. I also know that the telescope domes use titanium dioxide paint to keep out as much heat as possible, so would also appear bright white.
Back in olden days when I worked at the Observatory, there were lots of scientific photographic emulsions available, IR-sensitive as well. I had worked with IR before, and used my own cameras as well as some interesting cameras Kitt Peak had to take shots similar to these 25 years ago. One of the more interesting ones was a big box camera made by one of the solar astronomers that had an 800mm focal length lens and used 8"X10" glass plates. Those were some amazing images. I'll have to dig out some of those plates and scan them - with a deep red filter, and a 30 second exposure the resolution was exquisite and haze penetration was astounding. So I was interested in how close I could get to those results with today's digital detectors.
Here are a couple comparisons with the same lens set to the same zoom setting taken a few minutes apart on a hazy afternoon - the IR image with the modified 20D and the color images with the Canon Xsi. As always, click on the image to load a full-size version. The main thing to note is the dark sky - higher contrast of any cloud features, white vegetation, and good haze penetration. Note that there is a little subtle color - the sky sometimes comes out a little sepia toned, and vegetation a little blue. As I understand it, normally only the red-filtered pixels should show any IR signal, but the blue and green-filtered ones have a varying amount of IR leakage, so some subtle colors result. This effect can be magnified in Photoshop, but these are basic out-of-the camera results, using the custom white balance the camera-modifier set for me. I'll get a little more adventuresome later!
Another experiment before me is to use a deeper IR filter. The filter Jim Chen installed in front of the detector (in all operational respects, the camera behaves like a normal camera with the filter in front of the sensor) cuts on right at the limit of the eye's sensitivity. I've got a filter or two that transmit much further into the IR, so should get much better haze penetration at the expense of not seeing anything through the viewfinder, since this other filter will be in front of the lens! There are also some interesting astronomical applications - for sure I'll be bringing the camera to the RTMC telescope makers conference this weekend - hopefully Olivier Thizy will be there with his spectrograph again and I can directly measure the spectral sensitivity! I foresee fun times ahead!
Back in olden days when I worked at the Observatory, there were lots of scientific photographic emulsions available, IR-sensitive as well. I had worked with IR before, and used my own cameras as well as some interesting cameras Kitt Peak had to take shots similar to these 25 years ago. One of the more interesting ones was a big box camera made by one of the solar astronomers that had an 800mm focal length lens and used 8"X10" glass plates. Those were some amazing images. I'll have to dig out some of those plates and scan them - with a deep red filter, and a 30 second exposure the resolution was exquisite and haze penetration was astounding. So I was interested in how close I could get to those results with today's digital detectors.
Here are a couple comparisons with the same lens set to the same zoom setting taken a few minutes apart on a hazy afternoon - the IR image with the modified 20D and the color images with the Canon Xsi. As always, click on the image to load a full-size version. The main thing to note is the dark sky - higher contrast of any cloud features, white vegetation, and good haze penetration. Note that there is a little subtle color - the sky sometimes comes out a little sepia toned, and vegetation a little blue. As I understand it, normally only the red-filtered pixels should show any IR signal, but the blue and green-filtered ones have a varying amount of IR leakage, so some subtle colors result. This effect can be magnified in Photoshop, but these are basic out-of-the camera results, using the custom white balance the camera-modifier set for me. I'll get a little more adventuresome later!
Another experiment before me is to use a deeper IR filter. The filter Jim Chen installed in front of the detector (in all operational respects, the camera behaves like a normal camera with the filter in front of the sensor) cuts on right at the limit of the eye's sensitivity. I've got a filter or two that transmit much further into the IR, so should get much better haze penetration at the expense of not seeing anything through the viewfinder, since this other filter will be in front of the lens! There are also some interesting astronomical applications - for sure I'll be bringing the camera to the RTMC telescope makers conference this weekend - hopefully Olivier Thizy will be there with his spectrograph again and I can directly measure the spectral sensitivity! I foresee fun times ahead!
Sunday, May 17, 2009
Kitt Peak Star-B-Que!
About twice a year, the Tucson Amateur Astronomy Association (TAAA) schedules an afternoon cookout and evening's observing for members at Kitt Peak National Observatory's (KPNO) picnic area. Located about a 55 mile drive southwest of Tucson, and located at about 6500 feet elevation, it is an excellent choice for an event like this. The skies are great, and with the pavilion and scattered picnic tables in the area, it can't be beat. The TAAA has been running events here for over a dozen years or so, and even when the weather is bad, it is still a nice place to go to escape the desert heat for some camaraderie and a pot-luck meal.
Folks started arriving shortly before 4pm when the mountaintop closed to the public (the picnic area is about 1.5 miles down the road from the peak). The gas grill was started as members set up their telescopes for the night's observing. With moonrise at about 1am, and permission to stay even later, it looked to be a great night of observing. Some daytime scattered clouds were not an issue, though the horizons were very hazy. By 6pm, the scopes were ready and most members were stuffed by the food. Highlights for me was the guacamole Verne made table-side, and the home-made potato salad by Donna and Mike. We brought brownies from a mix that were also well received.
The highlight of this evening was perhaps the opportunity to observe the sunset through the world's largest solar telescope. The McMath-Pierce Telescope has a 60" diameter mirror that focuses an 80cm (30") image of the sun onto a screen. About 30 of us gathered there at 6:30 for the tour and observing session organized by Clyde Plymate, a TAAA member who works for the National Solar Observatory . The 3-mirror system was analogous to a Newtonian telescope, Clyde informed us - the long focal length resulting in a large image size about 3X brighter than ambient sunlight, rather than a focused spot that would catch something ablaze. Sunglasses were convenient to use to dim the image slightly, but the unfiltered image wasn't too uncomfortably bright. Unfortunately, though there was some plage activity as well as granulation visible, there were no sunspots - solar activity remains low even though we're well past the minimum stage of the cycle.
At one point, a jet was seen transiting the image - likely somewhere over California or near the west coast, it took about 20 seconds to traverse the solar image. As the plane exited the edge of the solar image, the hot exhaust gasses trailing it also dragged some of the light from the sun's disk - a really cool effect!
As time passed, the white, circular image of the sun became oblate and reddened as it approached the horizon. Eventually the horizon was spotted rising into the tracked solar image and cut off the disk. Interestingly, even though the horizon was perhaps 100 miles or more away, the tiny silhouettes of saguaro cacti could be seen in profile on the sun's disk - it really was an amazing sight - thanks Clyde!
Shortly we all returned to the picnic area, our telescopes and the quiet murmur of the astronomers as comments were passed along and calls were made to share views. I had my 14" Celestron set up for visual use (no photography early on, at least), and a highlight for me was when I installed a binoviewer (a prism arrangement to allow both eyes to view the image) I obtained almost a year ago, to view Saturn, it's edge-on rings and 4 or 5 moons that were visible. You had to battle collimation and focus issues, but when properly adjusted, it was quite breathtaking. Many of the old favorites were enjoyed by all - The great globular cluster M13 was observed in Hercules to acclaim, but then compared to the 4X bigger globular Omega Centauri just clear of the southern Horizon, most were left just speechless! Spring is galaxy season, and favorites from M81 and M82 near Ursa Major to NGC 4565 (Needle galaxy in Coma Bernices) and NGC 5128 (Centaurus A radio galaxy) were shared.
Eventually the crowd thinned, and I got out the camera and tripod, hoping to catch some "star party action". Unbeknownst to them, I imaged Michael and Mary Turner (60s w/28mm F/2.8 lens ISO 800) working on their observing list of star clusters, Mary at the star charts, while Michael moved from over her shoulder to telescope. What made the picture interesting was the constellation of Scorpius rising over them and some of the star clouds of the Summer Milky Way (still invisible naked eye) making their appearance. After that, I mounted the camera (Canon XSi) with a zoom lens piggyback onto the C-14, using it as a tracking platform to follow the stars. Even with the haze and scattered clouds near the southern horizon, I chose to shoot one of my favorite areas near Antares in Scorpius. It is full of globular clusters, both reflection (starlight reflecting off gas clouds), emission nebulae (gas clouds excited to emission from UV light from nearby stars) and dark clouds, seen in silhouette against the Milky Way. The result is a "quick and dirty" straight average of 30 minutes (10X3m each) of exposure with the camera and zoom lens set to F/3.2 and about 120mm focal length. It calls for more exposure, but it looks nice for a short effort!
The crowd continued to decline, finally, Michael and Mary left, then Donna and Mike left as we finished packing up the scope. Still before moonrise, we made it to Tucson an hour later, the moon by then revealing a multitude of high, thin clouds.
Dark of the moon and an earlier-rising Milky Way call for attention this coming weekend, but we're headed to California for the Memorial Day weekend Riverside Telescope Makers Conference up in Big Bear, my 22nd. Melinda has never been to California, so should be a fun time for us both!
Folks started arriving shortly before 4pm when the mountaintop closed to the public (the picnic area is about 1.5 miles down the road from the peak). The gas grill was started as members set up their telescopes for the night's observing. With moonrise at about 1am, and permission to stay even later, it looked to be a great night of observing. Some daytime scattered clouds were not an issue, though the horizons were very hazy. By 6pm, the scopes were ready and most members were stuffed by the food. Highlights for me was the guacamole Verne made table-side, and the home-made potato salad by Donna and Mike. We brought brownies from a mix that were also well received.
The highlight of this evening was perhaps the opportunity to observe the sunset through the world's largest solar telescope. The McMath-Pierce Telescope has a 60" diameter mirror that focuses an 80cm (30") image of the sun onto a screen. About 30 of us gathered there at 6:30 for the tour and observing session organized by Clyde Plymate, a TAAA member who works for the National Solar Observatory . The 3-mirror system was analogous to a Newtonian telescope, Clyde informed us - the long focal length resulting in a large image size about 3X brighter than ambient sunlight, rather than a focused spot that would catch something ablaze. Sunglasses were convenient to use to dim the image slightly, but the unfiltered image wasn't too uncomfortably bright. Unfortunately, though there was some plage activity as well as granulation visible, there were no sunspots - solar activity remains low even though we're well past the minimum stage of the cycle.
At one point, a jet was seen transiting the image - likely somewhere over California or near the west coast, it took about 20 seconds to traverse the solar image. As the plane exited the edge of the solar image, the hot exhaust gasses trailing it also dragged some of the light from the sun's disk - a really cool effect!
As time passed, the white, circular image of the sun became oblate and reddened as it approached the horizon. Eventually the horizon was spotted rising into the tracked solar image and cut off the disk. Interestingly, even though the horizon was perhaps 100 miles or more away, the tiny silhouettes of saguaro cacti could be seen in profile on the sun's disk - it really was an amazing sight - thanks Clyde!
Shortly we all returned to the picnic area, our telescopes and the quiet murmur of the astronomers as comments were passed along and calls were made to share views. I had my 14" Celestron set up for visual use (no photography early on, at least), and a highlight for me was when I installed a binoviewer (a prism arrangement to allow both eyes to view the image) I obtained almost a year ago, to view Saturn, it's edge-on rings and 4 or 5 moons that were visible. You had to battle collimation and focus issues, but when properly adjusted, it was quite breathtaking. Many of the old favorites were enjoyed by all - The great globular cluster M13 was observed in Hercules to acclaim, but then compared to the 4X bigger globular Omega Centauri just clear of the southern Horizon, most were left just speechless! Spring is galaxy season, and favorites from M81 and M82 near Ursa Major to NGC 4565 (Needle galaxy in Coma Bernices) and NGC 5128 (Centaurus A radio galaxy) were shared.
Eventually the crowd thinned, and I got out the camera and tripod, hoping to catch some "star party action". Unbeknownst to them, I imaged Michael and Mary Turner (60s w/28mm F/2.8 lens ISO 800) working on their observing list of star clusters, Mary at the star charts, while Michael moved from over her shoulder to telescope. What made the picture interesting was the constellation of Scorpius rising over them and some of the star clouds of the Summer Milky Way (still invisible naked eye) making their appearance. After that, I mounted the camera (Canon XSi) with a zoom lens piggyback onto the C-14, using it as a tracking platform to follow the stars. Even with the haze and scattered clouds near the southern horizon, I chose to shoot one of my favorite areas near Antares in Scorpius. It is full of globular clusters, both reflection (starlight reflecting off gas clouds), emission nebulae (gas clouds excited to emission from UV light from nearby stars) and dark clouds, seen in silhouette against the Milky Way. The result is a "quick and dirty" straight average of 30 minutes (10X3m each) of exposure with the camera and zoom lens set to F/3.2 and about 120mm focal length. It calls for more exposure, but it looks nice for a short effort!
The crowd continued to decline, finally, Michael and Mary left, then Donna and Mike left as we finished packing up the scope. Still before moonrise, we made it to Tucson an hour later, the moon by then revealing a multitude of high, thin clouds.
Dark of the moon and an earlier-rising Milky Way call for attention this coming weekend, but we're headed to California for the Memorial Day weekend Riverside Telescope Makers Conference up in Big Bear, my 22nd. Melinda has never been to California, so should be a fun time for us both!
Friday, May 15, 2009
New Mirror Lab Project!
Work at the Steward Observatory Mirror Laboratory continues on the Giant Magellan Telescope (GMT), as well as the Large Synoptic Survey Telescope (LSST). In recent months I've posted numerous times about LSST as that is the project keeping me busy. But now, the entire casting lab is humming with activity as they prepare to cast another telescope mirror - this time a 6.5 meter diameter mirror for the San Pedro Martir Telescope for the Observatorio Astronomico Nacional (Mexico's National Astronomy Observatory).
Work has actually been proceeding for a couple months now, but just yesterday, the casting crew started installing cores into the mold, and progress is visible from hour to hour. In the top image, among the dust collection system, pneumatic lines for tools, gangplanks for access and materiel transfer, is the rotating oven and the beginnings of mold construction.
The lab is full of the hexagonal solids that are used for the mold. Made of an alumina silicate ceramic, these "soft" refractories are machined in a computer numeric control (CNC) mill to shape and length, depending where they go into the mold. Because of 6-fold symmetry, there still needs to be 170 program routines written for the 1020 cores for this casting. After a visual inspection, they are individually subjected to a vacuum test to verify there are no flaws or defects that will affect the strength of the mold from the stresses of casting.
Phil runs the CNC mill. After loading the blank into the mount and initializing the program, the computer takes control going through 7 or 8 tool changes, cutting the hexagon to the proper diameter, radiusing the sharp edges, cutting the crosspin holes and mounting post to the right diameter and length, and then cuts the hex to the length and angle for it's proper position in the mold (the height of the mirror surface changes about 30cm (12") from edge to center). After another inspection and another step or two, the core is ready for installation.
While the "standard" core shape is hexagonal, there are some unusual shapes needed to transition to a round inside diameter, as well as the round outer diameter. The strange shapes also require custom blanks, some handmade, so those are made earlier, rather than later. Here is a shelf unit filled with some of the stranger shapes required around the outside.
While the start of core installation starts in the center, you can see here that a considerable amount of work has already been done. Inner and outer tub walls (all seen in the top picture)were installed a couple months ago, wrapped with inconel bands for strength at high temperatures, and prefired to "seat" the bands. The "hard refractory" walls and floor were then lined with soft refractories which were then machined to form the outline of the back and sides of the mirror blank. These soft refractories are easily damaged, so there is a double layer of a working surface to help distribute the weight of workers.
The general form of the lightweight mirrors produced at the Lab is that of a faceplate and backplate about 2.5cm (1") thick, with a rib structure about 1cm (.5") thick, not unlike an I-beam - stiff and relatively lightweight. Of course, the inner tub forms the inner hole in the mirror to allow the light to reach the Cassegrain focus of the telescope. You can also see the gaps between the cores that will form the ribs, once the mold is filled with glass. The tops of the cores are installed last, as the cores must remain open to machine and install the cross-pins between the cores to help the mold rigidity during casting.
Here Randy installs a core into a spot defined by a guide frame, insuring that it is located correctly, and square to the optical and mechanical axis of the casting. The core is held down by a bolt made of hard refractory (that is what the torque wrench is for). And the pneumatic tool is actually a reamer that opens the crosspin hole to the right taper diameter for gluing in the crosspin, which Randy is getting from Jim at the photo at right. For a practiced team, the work proceeds rapidly - the 18 or so cores installed here represents just a few hours effort, though for the 900 cores, likely over a month will be required, followed by a cleaning, prefire, and another inspection before glass loading and the actual casting, currently scheduled for early fall. Stay tuned!
Work has actually been proceeding for a couple months now, but just yesterday, the casting crew started installing cores into the mold, and progress is visible from hour to hour. In the top image, among the dust collection system, pneumatic lines for tools, gangplanks for access and materiel transfer, is the rotating oven and the beginnings of mold construction.
The lab is full of the hexagonal solids that are used for the mold. Made of an alumina silicate ceramic, these "soft" refractories are machined in a computer numeric control (CNC) mill to shape and length, depending where they go into the mold. Because of 6-fold symmetry, there still needs to be 170 program routines written for the 1020 cores for this casting. After a visual inspection, they are individually subjected to a vacuum test to verify there are no flaws or defects that will affect the strength of the mold from the stresses of casting.
Phil runs the CNC mill. After loading the blank into the mount and initializing the program, the computer takes control going through 7 or 8 tool changes, cutting the hexagon to the proper diameter, radiusing the sharp edges, cutting the crosspin holes and mounting post to the right diameter and length, and then cuts the hex to the length and angle for it's proper position in the mold (the height of the mirror surface changes about 30cm (12") from edge to center). After another inspection and another step or two, the core is ready for installation.
While the "standard" core shape is hexagonal, there are some unusual shapes needed to transition to a round inside diameter, as well as the round outer diameter. The strange shapes also require custom blanks, some handmade, so those are made earlier, rather than later. Here is a shelf unit filled with some of the stranger shapes required around the outside.
While the start of core installation starts in the center, you can see here that a considerable amount of work has already been done. Inner and outer tub walls (all seen in the top picture)were installed a couple months ago, wrapped with inconel bands for strength at high temperatures, and prefired to "seat" the bands. The "hard refractory" walls and floor were then lined with soft refractories which were then machined to form the outline of the back and sides of the mirror blank. These soft refractories are easily damaged, so there is a double layer of a working surface to help distribute the weight of workers.
The general form of the lightweight mirrors produced at the Lab is that of a faceplate and backplate about 2.5cm (1") thick, with a rib structure about 1cm (.5") thick, not unlike an I-beam - stiff and relatively lightweight. Of course, the inner tub forms the inner hole in the mirror to allow the light to reach the Cassegrain focus of the telescope. You can also see the gaps between the cores that will form the ribs, once the mold is filled with glass. The tops of the cores are installed last, as the cores must remain open to machine and install the cross-pins between the cores to help the mold rigidity during casting.
Here Randy installs a core into a spot defined by a guide frame, insuring that it is located correctly, and square to the optical and mechanical axis of the casting. The core is held down by a bolt made of hard refractory (that is what the torque wrench is for). And the pneumatic tool is actually a reamer that opens the crosspin hole to the right taper diameter for gluing in the crosspin, which Randy is getting from Jim at the photo at right. For a practiced team, the work proceeds rapidly - the 18 or so cores installed here represents just a few hours effort, though for the 900 cores, likely over a month will be required, followed by a cleaning, prefire, and another inspection before glass loading and the actual casting, currently scheduled for early fall. Stay tuned!
Wednesday, May 13, 2009
Cereus Giganteus
Since we are on the topic of native desert plants, time to address the Saguaro (sah-whar-oh) cactus. My eyes are usually a little bleary on the way to work, but am always on the lookout for cactus flowers on the way home in the afternoon. Saguaro flowers are rare on that schedule - they are night bloomers and are usually closed back up by noon.
There is a good sized cactus in front of neighbor Susan's house - likely a transplant as it is about 8 meters (over 25 feet) tall, and would be close to 100 years old at that height in the wild. These houses were built about 40 years ago, and in my 20 years here, it has always been over 5 meters (15 feet) tall. The first photo at left was taken yesterday afternoon from ground level. Lots of flower buds, but no blossoms 2 hours before sunset. The next photo was taken this morning, 2 hours after sunrise - lots of flowers with bees and insects too!
Despite the abundance of insects, the most important pollinators of saguaros (Cereus Giganteus or Carnegiea Gigantea) are bats. I was amazed a decade or more ago when one of our amateur astronomers brought in a night-time video of bats feeding on pollen and nectar from the flowers. They did this while flying past the open flowers, using their long tongues to reach far inside the flower! The closeup image here doesn't do it justice - realize I was shooting blind, with the camera atop a nearly 1.8 meter monopod held over my head using the autofocus and the self-timer, hoping to get a flower or two in the shot before I had to leave for work. There are future yet-to-blossom buds, as well as the wilted results of past blooms. An unusual-looking flower (no doubt adapted for it's unique method of pollination), it is the state flower of Arizona. If the flower was pollinated, a fruit will develop and ripen. Each fruit might contain thousands of seeds, and is heavily sought after by animals, as well at local Native Americans as an important food source. Hmmm, sounds like a July post...
There is a good sized cactus in front of neighbor Susan's house - likely a transplant as it is about 8 meters (over 25 feet) tall, and would be close to 100 years old at that height in the wild. These houses were built about 40 years ago, and in my 20 years here, it has always been over 5 meters (15 feet) tall. The first photo at left was taken yesterday afternoon from ground level. Lots of flower buds, but no blossoms 2 hours before sunset. The next photo was taken this morning, 2 hours after sunrise - lots of flowers with bees and insects too!
Despite the abundance of insects, the most important pollinators of saguaros (Cereus Giganteus or Carnegiea Gigantea) are bats. I was amazed a decade or more ago when one of our amateur astronomers brought in a night-time video of bats feeding on pollen and nectar from the flowers. They did this while flying past the open flowers, using their long tongues to reach far inside the flower! The closeup image here doesn't do it justice - realize I was shooting blind, with the camera atop a nearly 1.8 meter monopod held over my head using the autofocus and the self-timer, hoping to get a flower or two in the shot before I had to leave for work. There are future yet-to-blossom buds, as well as the wilted results of past blooms. An unusual-looking flower (no doubt adapted for it's unique method of pollination), it is the state flower of Arizona. If the flower was pollinated, a fruit will develop and ripen. Each fruit might contain thousands of seeds, and is heavily sought after by animals, as well at local Native Americans as an important food source. Hmmm, sounds like a July post...
Monday, May 11, 2009
Palo Verde
With the daily highs at or over 100F, the desert flower season is quickly drawing to a close. You can still spot some cacti in bloom, among them the Saguaros that are about the last to blossom. So you might yet see more images here.
I had to run in to work yesterday and this desert garden in front of The Optical Sciences Center (here looking towards the main library) caught my eye. The palo verde (pal-oh ver-day) trees (the Arizona State Tree), still sported some flowers, but what caught my eye were the "snowdrifts" of the yellow petals collected below. Palo verde (spanish for green stick) are spectacular native plants when they are ablaze with their flowers in mid-spring and can bloom again after the summer rains.
The plants are unusual in that they have chlorophyll in their branches and trunks (accounting for the green color), thus can generate energy via photosynthesis, even in times of drought when the tree will shed most of it's leaves. In the closeup, even now you can see most of the small leaves have been shed, and will generate new leaves during the summer rains in July and August. There are at least 3 species that live in the Tucson area - the foothills, blue and mexican varieties are all common. I believe these are foothills palo verdes.
I've been looking for some spectacular palo verde shots this spring, but the lack of springtime rain has cut back some on the displays. But I thought I would show some our tree blossoms to keep pace with all the flowering trees we saw in the Midwest last weekend!
I had to run in to work yesterday and this desert garden in front of The Optical Sciences Center (here looking towards the main library) caught my eye. The palo verde (pal-oh ver-day) trees (the Arizona State Tree), still sported some flowers, but what caught my eye were the "snowdrifts" of the yellow petals collected below. Palo verde (spanish for green stick) are spectacular native plants when they are ablaze with their flowers in mid-spring and can bloom again after the summer rains.
The plants are unusual in that they have chlorophyll in their branches and trunks (accounting for the green color), thus can generate energy via photosynthesis, even in times of drought when the tree will shed most of it's leaves. In the closeup, even now you can see most of the small leaves have been shed, and will generate new leaves during the summer rains in July and August. There are at least 3 species that live in the Tucson area - the foothills, blue and mexican varieties are all common. I believe these are foothills palo verdes.
I've been looking for some spectacular palo verde shots this spring, but the lack of springtime rain has cut back some on the displays. But I thought I would show some our tree blossoms to keep pace with all the flowering trees we saw in the Midwest last weekend!
Saturday, May 9, 2009
Midwest Springtime Recap
As our previous post indicates, we really spent too little time in Illinois. Springtime was just starting in earnest and the trees were just leafing out. Since our return to Tucson, we've gone 101F Thursday, 102F yesterday, and it is supposed to be over 100 again today. Our temp sensor says 109.9F, but is mounted under the eave of the roof, so I think it is catching rising warm air in the afternoon. A dry heat, yes, but I do not enjoy getting into a 150F car to go somewhere! At left is an IR shot of "Ketelsen East" with geese (non-domestic)!
So yes, the 70s of Illinois were very pleasant, and there were many flowers and trees in bloom, even if the trees were not all green yet. I don't want to bore you with endless pictures of tulips (at their peak), and the large number of planted flowering trees - would prefer to show the more native species we spotted on our walks.
In our exploration of the nearby Tekakwitha Forest Preserve, besides the violets (white and yellow besides the normal blue kind!) and dandelions, the trillium was in bloom. Besides the white variety, my favorite was the Trillium Recurvatum, also known as Red or Prairie Trillium, shown at left. Never having spent much time in any natural woods growing up in Iowa, these flowers were new to me and they are quite striking. Evidently the odor of the seeds attract ants, which then help distribute them. The White Trillium, also in bloom in the woods and in our back yard, serves as the state flower of the province of Ontario and of Ohio.
Another striking "bloom" is shown in this series. What looked initially like an about-to-open flower, is actually part of the leaf bud of the Shagbark Hickory. We first spotted the closed bud on the left, but then noticed some that had recently opened, and eventually an adult tree with new growth on it. According to naturalists at the Forest Preserve, the area we live in there is officially called a "Declining Oak-Hickory Forest", declining because the maple trees are slowly shading out the Hickory and oak trees. However, once we realized these buds pointed out the Shagbarks, they seems quite numerous and widespread.
Normally, there are trails in the Forest preserve we like to take to get us away from the bike path and civilization, but the river had been out of the banks recently and the trail was too muddy to follow very far. However, I didn't have to follow it far to observe signs of larger animals - here deer tracks can be seen over some muddy bootprints from another hiker. In addition, the Canadian Geese eggs have hatched, and there are goslings everywhere! We saw several groups as big as 9 little 'uns near our house, and I ran into these 3 staying near mom on my short time on the trail.
During our short stay at "Ketelsen East", we even ran into our neighbor groundhog Bruce, not once or twice, but 3 times over 4 days! Last year he was mostly absent until nearly fall, but he was certainly there to welcome us last weekend (though I didn't get a photo this time). Our house is occupied, though, even if we aren't there - we found this robin in a well built nest over an exterior light on our door facing the Fox River. By the time we get back for another visit, the babes will just about grown up and ready for flying lessons!
A commenter points out that the Ohio State flower is the Scarlet Carnation. Actally, the White Trillium is the Ohio State Wildflower. Sorry for the confusion.
So yes, the 70s of Illinois were very pleasant, and there were many flowers and trees in bloom, even if the trees were not all green yet. I don't want to bore you with endless pictures of tulips (at their peak), and the large number of planted flowering trees - would prefer to show the more native species we spotted on our walks.
In our exploration of the nearby Tekakwitha Forest Preserve, besides the violets (white and yellow besides the normal blue kind!) and dandelions, the trillium was in bloom. Besides the white variety, my favorite was the Trillium Recurvatum, also known as Red or Prairie Trillium, shown at left. Never having spent much time in any natural woods growing up in Iowa, these flowers were new to me and they are quite striking. Evidently the odor of the seeds attract ants, which then help distribute them. The White Trillium, also in bloom in the woods and in our back yard, serves as the state flower of the province of Ontario and of Ohio.
Another striking "bloom" is shown in this series. What looked initially like an about-to-open flower, is actually part of the leaf bud of the Shagbark Hickory. We first spotted the closed bud on the left, but then noticed some that had recently opened, and eventually an adult tree with new growth on it. According to naturalists at the Forest Preserve, the area we live in there is officially called a "Declining Oak-Hickory Forest", declining because the maple trees are slowly shading out the Hickory and oak trees. However, once we realized these buds pointed out the Shagbarks, they seems quite numerous and widespread.
Normally, there are trails in the Forest preserve we like to take to get us away from the bike path and civilization, but the river had been out of the banks recently and the trail was too muddy to follow very far. However, I didn't have to follow it far to observe signs of larger animals - here deer tracks can be seen over some muddy bootprints from another hiker. In addition, the Canadian Geese eggs have hatched, and there are goslings everywhere! We saw several groups as big as 9 little 'uns near our house, and I ran into these 3 staying near mom on my short time on the trail.
During our short stay at "Ketelsen East", we even ran into our neighbor groundhog Bruce, not once or twice, but 3 times over 4 days! Last year he was mostly absent until nearly fall, but he was certainly there to welcome us last weekend (though I didn't get a photo this time). Our house is occupied, though, even if we aren't there - we found this robin in a well built nest over an exterior light on our door facing the Fox River. By the time we get back for another visit, the babes will just about grown up and ready for flying lessons!
A commenter points out that the Ohio State flower is the Scarlet Carnation. Actally, the White Trillium is the Ohio State Wildflower. Sorry for the confusion.