Sunday, March 29, 2015

Ringy Dingy!

We've had cloudy skies most of the day, and also have a 10-day-old gibbous Moon tonight, so figured I had little to no chance of coming up with a blog post, but what do you know - stepped outside to pick up cat food bowls and found a really nice ring around the moon!

This 22 degree halo is caused by moonlight (or sunlight during the daytime) refracting through two surfaces of hexagonal ice crystals in the clouds. Longer wavelengths are refracted a little less, so the inside of the halo shows a red fringe. This is an 8 second exposure with wide angle zoom set to 14mm, and really approximates the visual appearance pretty well. Ain't optics wonderful!?

Fortunately it is clear enough to see a few other objects along the red-fringed ring and moon. Brilliant Jupiter is up at the 10 o'clock position from the moon, and there are a few stars too. At left just inside the ring at 8 o'clock is Regulus, the brightest star in Leo, and also just inside the ring at 3 o'clock is Procyon (Alpha Canis Minoris). At the top of the image, splitting the ring are Castor and Pollus (top to bottom), in Gemini. Just in case you can't see all that, I'm providing a labeled version at right. I lucked out to find an astronomy-themed subject tonight - yippee!

Thursday, March 26, 2015

A "New" Star in the Morning Sky!

Usually at 4am I'm watching the backs of my eyelids, but recent events prompted me to step outside after heeding nature's call at that time. Recent reports of a "bright" nova in the constellation Sagittarius motivated me to try capturing it with camera and tripod. It was clear (and cool, given that the daytime highs are in the mid-80s these days), so quickly set up. I used an 85mm Canon lens at F/2 and took a few exposures at 3.2 and 5 seconds - 7 frames total, only 28 seconds total exposure.  I kept the exposures short to reduce trailing and stacked the untracked images to make the image shown here. The field barely fits the asterism of "The Teapot" into the frame. In case you don't see it, I've included lines and labels in the right image.  The darkening or vignetting in the corners results from shooting with the lens nearly wide open, and is to be expected, especially in a bright sky like we have in town.

Nova are caused by mass transfer in a binary star system.  Hydrogen gas collects on the surface of an aged white dwarf, and when enough fresh fuel transfers, a runaway nuclear reaction takes place, resulting in a huge brightness increase - in this case about 10 magnitudes, or 10,000 times brighter than the progenitor star. 

Of course these things don't last long, so get a glance while you can. Current light curves show it right on the verge of naked-eye visibility from a dark site, but will require binoculars most everywhere else.  Using the "official" AAVSO map at left, you can track the brightness yourself, using nearby comparison stars where the brightness is listed on labeled stars without decimal points.

Have fun and get out there!

Ancient Photons!

These recent posts involving Kitt Peak National Observatory and infrared imaging remind me of my early days first working there, 35 years ago!  As a fresh-faced farm boy transposed to the mountaintop astronomical paradise, I was entranced.  At the time, we oversaw 9 telescopes and the astronomers that used them, as opposed to, I believe, just one that goes through the twice-annual telescope allocation committee meetings today...  Those were pre-digital sensor days - most every telescope had darkrooms that had to be kept stocked, and refrigerated plate vaults full of not the film rapidly fading from our memory, but real glass plates of a wide variety of astronomical emulsions.  As staff, we were encouraged to be acquainted with both hardware and processes, so even on my days off, I dove right into a number of projects.

One of them I briefly mentioned a week or so ago in locating the furthest point visible from the mountaintop.  One of the solar astronomers had constructed a huge camera, a yard long and 12" square that used a 36" focal length (900mm!) lens that took 8X10 glass plates. Fortunately there was an ample supply of expired plates to use up, and I chose to use infrared sensitive plates with a filter transmitting so far into the red that you couldn't see anything through it (RG 780). Digging through the plates recently, I brought them to a local lab to have a couple scanned so I could show them here. At left is shown an example of the full frame on IV-N infrared-sensitive emulsion. Taken in June of 1980, it is a 10 second exposure, both because of the low sensitivity of the base emulsion, and also because of the stopped-down aperture to extend the depth of field from the nearby domes to distant Baboquivari. Of course, as stated recently, the main effects of IR imaging is darkened sky, lightened vegetation, and haze penetration. Baboquivari is a full 15 miles south of the Observatory, so it does indeed work well in penetrating haze!

What you can't see from the images is where I was when taking them... I was actually on the 4-meter exterior catwalk located outside the big dome, about 100 feet off the ground. It was one of my favorite places on the mountain so far off the ground atop the highest mountain around. Unfortunately seven years later it became the location of a horrible accident where astronomer Marc Aaronson was killed and the exterior catwalk was closed off for all access. The image at right labels the telescopes located there at the time.

Believe it or not, things change in 35 years! While two of those structures are still there, all of the scopes have changed... Shown here is a view of the south ridge from the 4-meter visitor's gallery a couple years back (no changes since then). The #1-36 was removed in 1992 when ground was broken for the 3.5 meter WIYN telescope to be built in that prime location. The "best parts" of the #1 and #2 36" scopes were combined and eventually became just the .9 meter telescope, then was transferred to the WIYN consortium in 2001. The other parts of the 2 combined telescopes, were relocated on the mountain and became the SARA Telescope (SARA- Southeast Astronomy Research Association). The "Pima Tower", an early seeing monitor for long-term Polaris observing, was removed. And at some point, the #4-16" telescope was removed, and a number of scopes in recent history were used for Visitor Center use, most recently a donated 16" on a beefy mount.

The other IR plate exposure I had scanned is shown at left. There is a miniscule overlap, but they were taken from different vantage points so couldn't be combined... Here also, there have been some major changes in 35 years - the labeled version is at right. The Burrell Schmidt, one of the most beautiful restored telescope, is just right of center and had been installed just as I started work in 1979.  So when this image was taken, it was less than a year old. Originally built and installed in Cleveland, OH (!) in 1939, it was moved to a countryside location in the 50s before its move to Kitt Peak in 1979.  During its move, KPNO photographic scientist Bill Schoening, an expert in auto restoration, totally stripped, repainted and re-chromed the telescope. It is still there, but converted to CCD detectors, and NOAO has given up its interest in the telescope (operated by Case Western Reserve). When I arrived the dome adjacent to it at right housed a 12" Schmidt that was unused. I cleaned and used it for a while before it was given away to another institution. Another instrument used the structure for a while, which needed full-sky access, so the dome was removed and a roll-off roof was installed. When the visitor center started their public programs, they installed a 16" telescope for use. To that dome's right, the airglow dome was removed ages ago and is now a storage shed.  Looking at the newer image above, the SARA telescope is just beyond this building and houses the parts left over from the reconstructed 36" as explained above.  That is a long-winded explanation of most of the changes I've seen since these images were taken...

Since these images are off 8X10 plates, there is a LOT of information on them. Cheapskate me, I didn't spring for the expensive hi-resolution scan ($25 each for these seemed high enough for me!), but there is much to be seen in close examination. Admittedly I wasn't paying attention to what was going on nearly a km away from where I was standing with the camera. But the camera captured a visitor who stood stock still for the 10 second exposure reading the signage on the 4-meter concrete mirror dummy. Also interesting is that perhaps his spouse was walking towards him from the restrooms at right - you can see the ghostly image of their feet where they were stationary for fractions of a second during the long exposure. And a little higher, you can see the US and what I think is the Tohono Nation flag on the pole near the kitchen, with the 1.3 meter dome at right. The flags are blurred from the long exposure, but also, the IR wavelengths tend to wash out even strongly colored inks and dyes. It is still interesting to me how well the individual bushes stand out on the distant ridgeline in the background at least 6 or 8 miles away! These images are shown at the full-resolution of the less-expensive scans...

Anyway, that is it for my ancient history lesson on Kitt Peak from long ago. It seems interesting that these images, which take up considerable space, are not easy to lose track of. With digital images, will it be as easy to keep track and pull up an image 35 years down the road? Given how hard it is to read a 3.5 inch floppy from 10 years ago, it remains to be seen!

Tuesday, March 24, 2015

Word Of The Day!

The word of the day - anaglyph, a method of viewing 3D scenes! Those who know me also know I'm a 3D nut - there are lots of posts (29 to date!) where I've given our followers headaches trying to fuse pictures to show depth in an scene. After the flight with Chuck the other week, and a plethora of images taken as we fly along, I needed a method to show off the 3D effect, and a new method (for me) is the anaglyph method. In previous posts, I've presented the images separately to freeview them by either the cross-eyed or parallel-view method. The advantage of those is that with practice, you generally don't need a viewer. The disadvantage is that most get frustrated, and images need to remain small, and detail is lost. With anaglyph viewing, each image is tinted red or cyan, and using cheap cardboard glasses, each eye sees the appropriate image for your brain to reconstruct the image. So if you have the red and blue-green glasses, get them out - time to put them to use!

By the way, I found the method used to make these from Googling "how to make an anaglyph" and one of the top returns was "Simplest Method of Making Anaglyphs", and sure enough, it is only a couple steps, in fact, it may be simpler than the work I had to go through to make the two-image pairs previously... Since many of you may not have the colored glasses, I'll continue to provide an alternate, the cross-eyed method works best for me - when looking at the image pair, cross your eyes slightly to view the right image with your left eye and vice-versa. You should see a center image that shows depth. Try it first on the smaller thumbnails before clicking on the image for the full-size image...

First up is a pair taken as we flew past Kitt Peak National Observatory on our outbound flight, our height just above that of the Observatory. Taken a few seconds apart, our motion provided the baseline for these "hyperstereos", whenever the baseline is farther than your eye separation. Again, at left is the cross-eyed version, and at right is the anaglyph view.

I love these hyper-stereos as the depth of the scene is accentuated.  Nearly each dome at the Observatory stands out and depth can be seen almost to the distant mountains. 

After our flight out to western Pima County, our return brought us back past Baboquivari Mountain. It is a spectacular peak - I've had the pleasure of hiking to the top 3 or 4 times back a few decades ago. It is considered by the Tohono O'odham tribe the center of the universe and home to their deity, I'itoi, Elder Brother. Since it was out my window on the right side of the plane, I took several series of images, one of which I made into this stereo pair. Again, with the wide baseline depth details can be seen from the incredibly rugged foothills to distant mountains. Interestingly, in the anaglyph at full size, I can almost retrace the hiking route up the northern side of the peak...

On our return trip we were at about 10,000 foot elevation, so about 3,000 feet above both Baboquivari and Kitt Peak. As we passed the Observatory again, another hyper-stereo is shown, showing depth details from domes to distant canyons past Baboquivari 15 miles away.   I'm really loving the anaglyphs, particularly with these B&W IR shots, since they interfere less with color fidelity, and the larger sized images retain more detail than the necessarily small individual frames for free-viewing.

So I'm looking for feedback, particularly if you have the red/cyan glasses.  I'm guessing that would be the favorite way for viewing these, so since I'm boss around here, will likely continue, perhaps continuing presenting the cross-eyed view too for now.

Saturday, March 21, 2015

Look to the West!

The multi-planet alignments in the western sky at sunset are slowly coming to an end. Mars and Venus, so close a month ago, are now widely separated, and Uranus, visible next to Mars just 10 days ago, is nowhere to be seen as it appears to move too close to the sun from our perspective. Tonight, however, the moon, fresh from its solar eclipse Friday morning in far northwestern Europe, appeared tonight (Saturday) adjacent to Mars. I drove up to "Bad Dog" overlook on the Mount Lemmon Highway to improve my western horizon. I arrived minutes before sunset, and was able to barely capture the moment of sunset behind the Tucson Mountains about 24 miles away, and the saguaro cacti on the slopes of the Catalinas considerably closer. I enjoyed the view of city lights coming up as the Moon/Mars conjunction became visible.

I wasn't sure how close Mars and the Moon would appear - I was hoping to use the William Optics 11cm, F/7 refractor used for the sunset above, but once Mars popped out, it wouldn't quite fit with the 770mm focal length. Fortunately, I was prepared and brought my smaller Meade 80mm F/6 for 480mm of focal length for the view shown at left. Mars is in the lower left, and if you click the image to load the full-size view, you can also spot a couple of 6th magnitude stars in Pisces. Of course, the "dark side" of the Moon is visible because with the skinny crescent phase, from the Moon's surface, there is a nearly full Earth illuminating it. Called "Earthshine", it is easily seen during the crescent moon phase.

A little later as it got darker, I finally broke out the kit lens for the Canon XSi to take a wide-angle shot. Visible at left is the Moon/Mars pair, and also brilliant Venus above it. I went looking for the much dimmer planet Uranus, visible near these planets the last few weeks, but it has appeared to have dropped too close to the sun to spot.

There is still good reason to watch the west, though... Tomorrow (Sunday), the moon continues its path away from the sun and is adjacent to the brighter planet Venus - be on the lookout if your skies are agreeable!

Monday, March 16, 2015

Taking Flight!

Growing up in the flatlands of the Midwest, it wasn't till moving to Arizona that I discovered mountains.  They are magical places, not only cool and relatively lush compared to the desert floor, but the views from the high ground are spectacular!  It is likely the closest I routinely get to flying unless I join my buddy Chuck in his plane, which doesn't happen very often.  I had a little photo project to do from the air, and he was willing to oblige with a plane flight around Pima County last week.  More on that project later...

I met up with him at Ryan Field, where he keeps his Maule single prop plane.  While he fueled up, I figured we had nothing to complain about concerning gas prices in Tucson.  While we're paying $2.21 in town, the self-serve pump at the field is over twice that!

His lil' beauty is shown at left, parked off to the side while I moved my van into his hangar and used the facilities before takeoff.  If you click to see the full-size image, you will note the telescopes of Kitt Peak in the background  - our flight plan was to take us out past the National Observatory, and back in past it, so you'll see it again soon.  The quarters in the plane were a little cozy, but fine for an hour's flight.  He often works with photographers for his "tree hugger" work, so reviewed with me how to open my window for the best imaging results.  At right is a 3-frame mosaic (again, close quarters) as we're about to start taxiing.

Seemingly in a few minutes (it was closer to 15 with my nose pressed-to-window), we approached Kitt Peak.  I had 2 cameras with me - the usual Canon XSi I use for 95% of the images on the blog, the other was the Canon 20D I converted to IR use a few years back.  Most new cameras have good sensitivity in the IR, but most all have IR-blocking filters.  In this case, the IR-block was replaced with an IR-pass filter.  As a result, it has good haze penetration (with the longer wavelengths), light or white vegetation, and dark sky and bodies of water in a mostly-B&W image.  Unfortunately we had some light clouds this Wednesday morning, so the sky wasn't as dark as it would normally show, and some loss of contrast towards the horizon.  At left is one of the first IR shots approaching the mountaintop Observatory from the east, and about the same elevation as the peak.  At right is a color image, unfortunately directly down-sun, so no shadows to speak of...  You can see the haziness in the air in the distance...

That haze, showing up as bluish in visible light, is better penetrated with the longer wavelengths of IR.  The image at left taken a few seconds later is a good demonstration.  Mountain ranges are clearly seen off nearly to the horizon.  In addition, contrast in the ground details remains high.  Finally, as the last demonstration of IR radiation, bodies of water show as dark as they absorb IR.  There is a dam at the mouth of "Horseshoe Canyon" on the western slope of Kitt Peak, resulting in a small lake that is used as an emergency source of water.  Nearly all of the water used atop the mountain is collected and treated rainwater.  In any case, the lake shows as nearly black in this image

Anyway, the project in mind...  I've always wanted to know how far you can see from Kitt Peak.  Of course, at night, the tongue-in-cheek answer is that you can see 2.5 million light years with the naked eye to the Andromeda Galaxy.  My quest is for the furthest terrestrial point one can spot from the 7,000 foot elevation.  An image seen decades ago had one of the solar astronomers identify a peak to the west as a range on Baja.  I'm thinking they were assuming that Picacho del Diablo, over 10,000 feet was visible from nearly 250 miles away.  Identified in a recent post from Rocky Point, Mexico, this peak has a distinctive double-peak profile, and I was hoping with the IR wavelengths and higher elevation would make it more obvious, if visible at all.  An image at left from Kitt Peak, a mosaic with a small scope,  I'm thinking the Pinacates were mis-identified on that old photograph.  The task was to unambiguously identify these peaks and see if the far side of the Sea of Cortez could be spotted.

We proceeded past Kitt Peak and went another 25 miles a little past the reservation capital of Sells, while climbing to 10,000 feet.  About 5 miles short of the Mexican border we did a slow left turn while I took a series of exposures.  Assembled into an 11-frame mosaic, the Sea of Cortez was easily seen, but the cloudiness in my opinion limited visibility as far as seeing the far side.  A small part of it is shown at right, and shows a better view of the above visible panorama, including better identifications of Mount Cubabi and the Pinacate range, both in Sonora, Mexico.

On our return trip we passed Kitt Peak,
this time on its northern side.  This first wide view is almost directly up-sun, so not optimum conditions, but a nice perspective from a little-seen angle.  From this side, Horseshoe Canyon, where the lake is located as above, is easily made out bottom center.  There are radio as well as optical telescopes on the eastern ridge of the Canyon, well below the rest of the scopes atop the mountain.  A better view occurred five minutes later, shown at right, just showing the upper Observatory grounds.  With the vegetation showing up light in IR wavelengths, it is almost a "where's Waldo" game to find all the telescope domes hidden there!

One more comparison of the IR camera to the visible color camera can be done as we were on approach to Ryan Field to land.  Taken within a minute of so of each other, the IR image was taken first, then the color image taken, showing a lot of haze - even more than I recall seeing by eye.  Full disclosure though, these pictures were about the only ones taken through the front windshield...  Still the difference in the view of the "Tucson
Valley" is pretty amazing!

So the task to determine the furthest point visible from Kitt Peak is still "up in the air" so to speak.  I don't think Baja is visible, though if I can talk Chuck into another flight with better skies I'll be glad to go!

Saturday, March 14, 2015

Invasion of the Crane Flies!

It started a couple weeks ago - it seemed as though one of the plagues of Egypt had descended as swarms of mosquitos over 2 inches long arrived! Not only was Melinda freaking out, but even the cats were chasing the few that sneaked into the house. The local paper had a short article with an identification - they were Crane Flies, a harmless insect that appears in wet years. Since we've had a moist Winter and Spring, there you go! They certainly don't bite, and there is some discussions as whether or not they even eat during their 2 week life span.

But even though they are harmless, having these mosquito-looking bombers flying around your head sends you swatting...  Of course, I grabbed my macro lens and went a-hunting.  Fortunately they stop and rest occasionally.  At left is a shot showing the entire insect at our front door under our entry light.  The on-camera flash was used for illumination in all the images.  With the macro lens, I moved in near the closest-focus that resolved its compound eye at right.

One of the first images I took of the flies was through our sliding glass rear door. Viewing it from below at left, I noticed something interesting right away - it had a pair of stalks coming out of its abdomen near the wings, with little balls on them. They reminded me of the long poles that tightrope walkers use to maintain their balance. While the Wiki site above didn't identify the appendages, another site talking about crane flies in Texas identified them as halteres, which vibrate while in flight to provide a balance and guidance system - just what my first thoughts had been! In both this image and another on the front door from above (at right), they are quite apparent.

The wings are quite spectacular in close-up. They are gossamer-thin, almost transparent, yet have a stiffening structure embedded to strengthen them. They seem quite the marvel of engineering! While the adult insects only live a couple weeks at most, they do take a beating - note the wing close-up at left, which has suffered a puncture (marked with an arrow). Almost all careful wing examinations in my images showed similar tears and rips.

So they will be gone soon enough, but one of my nightly chores is still to dispose of the 6 or 8 that have managed to get into the house and gather around the lights in the kitchen and adjacent to the bed.