Wednesday, December 31, 2008

Happy New Year!

There is nothing like a fire in the chiminea outside the back door to take the chill off those mid-60 degree temps! As the sky darkened and the Moon-Venus conjunction was made apparent, we built a fire to enjoy the outdoor evening here in Tucson. While we feel a little guilty to abandon family and friends in the frigid Midwest, now that the normal cycle of clear skies and high temps in the 70s have returned to Arizona, this is the place to spend a winter! Wherever you are, we're glad you made it through 2008 and hope you have a fantastic 2009!

Monday, December 29, 2008

Planetary Alignment From Kitt Peak

Melinda and I were invited by David Harvey to join him over the weekend for his engineering/observing run on the 90" Bok Telescope of Steward Observatory at Kitt Peak. With the storm clearing late in the week, and our Whitewater Draw trip Saturday, Sunday was our only chance to overlap. Melinda had to work, but friend Laurie Larson wanted a chance for some photography, so she joined me for the trip. The 90" is shown in the foreground here from a previous KPNO visit. The "Bok Walk", a platform about 50 feet off the ground seen on the near side of the building in this shot was used as vantage point for all these photos.

Dave is a software engineer for Steward, so these runs occur occasionally, this run officially was to work on telescope collimation, but the other engineer called in sick, and the telescope was available for other applications. Dave had his own agenda, but graciously offered the scope to shoot an object two, and I took advantage of it. Dave is a professional photographer in Tucson (click on his blog link above!), and I picked up a lot in the few hours we spent together. The 90" images will be shown in a subsequent post. For the moment, I'm showing the planetary alignment that took place Sunday evening.

From Whitewater draw we spotted the Mercury/Jupiter alignment (see Saturday's post), and tonight, the moon was added to the mix. It was a spectacular late afternoon - about as clear as I've seen it from the mountain (where I worked for some years in the 80s). The Four Peaks area east of Phoenix showed almost no haze, a good indicator of the clarity. With the low sun blocked by an antenna, the shadows cast into the desert dust by intervening mountains forward-scattered to out viewing position. At the same time, the slightly asymmetric shadow of the mountain was cast into the sky to the east (since the 90" is on the north side of the mountain, the shadow is steeper on the left side. It would have been a perfect cone had we been a couple hundred yards to the south).

As it darkened, Jupiter, Mercury and the moon were easily visible, with Venus of course much higher and brighter in the sky. After taking this shot, I got distracted by starting an exposure sequence on the 90", but a subsequent check of the western horizon from the Bok Walk a little later showed the moon just about to set. Amazingly, as the moon set into the inversion layer (a common temperature inversion, common in Winter and observed visually as we climbed the mountain road earlier), the moon became wildly oblate and distorted from thermally induced refraction. It was an amazing sight and my favorite image of the evening (a 10 second exposure with the camera balanced on a cinder block wall!). Stay tuned for some shots through the 90" in one of my next posts!

Saturday, December 27, 2008

The Cranes of Whitewater Draw

Melinda and I made what was my 4th trip to Whitewater Draw (her second), a wildlife preserve built around a man-made wetlands where Sandhill Cranes spend their winters. Thanks again to Tom and Jenn Polakis who first exposed me to the place (with David Healy and Jeff Medkeff), about 25 miles east of Tombstone, AZ.

In all my previous trips, the "lake", varying between 10 and 40 acres, was literally crowded with up to 30,000 cranes. Today, at mid afternoon, it was totally devoid of cranes, though there were a few American Coots, Northern Shovelers, Buffleheads, Northern Shrikes, and a few others I've yet to ID. It was eerie - the normal din of tens of thousands of cranes was replaced by silence. The few birders braving the cold wondered where they were - we had seen and heard a few groups pass over, but none landed near the water.

Then, 'round about 4pm the masses arrived! From the north up towards Mt Graham (about 85 miles away), waves and waves of thousands of cranes descended, most all of them landing in a pasture about a mile to the west of us. The clouds of cranes could be seen tens of miles away. This photo shows 3 or 4 waves of them against the snow-covered Graham mountains, with ground fog near the base, and the LBT telescope seen on the western slope.

About the time dusk was falling, we could no longer stand the cold, and headed back to the car, there was a mass ascension from the pasture and the sky was filled with incoming cranes. We scrambled back down the trail to take these images. It really was amazing with them darkening the twilight sky. They slowly settled into the lake and we soon spotted Jupiter and Mercury through the masses. The sight and sounds of their calls is not to be soon forgotten.

Just for grins, before leaving I thought I would see if the camera flash would be bright enough to illuminate the closest of the bunch, perhaps 50 yards away. It was not, but interestingly, the cranes show a "catseye" effect where the light is reflected back to the source, making most all of them showing at least one eye brightly illuminated.

It would have been nice to stay and observe for a while, but we were already chilled to the bone. The cranes stay till mid February, so perhaps next dark of the moon. As it was, just the bird watching was memorable enough! BTW, all photos taken by the Canon XSi, the top 3 images taken with the 80mm Meade APO F/6, the last 3 with 70-200 F/2.8 Canon zoom.

Friday, December 26, 2008

Pictures to follow...

Merry Christmas (a day late) everyone! Dean took the pictures and I'll have to remind him to get them on here later today!

We had a wonderful day, despite my employer insisting that I work on the 24th and 25th! Dean was still in bed when I got home from work, but I coerced him out of bed - promises of presents! We had so many gifts from our relatives to open that it took a long time before we got to the presents we were giving each other! We both agreed that we must have "been very good" this year! Dean (knowing my fondness for home improvement) gave me a full set of cordless tools (drill, circular saw, reciprocating saw, flash light, and dust vac)! Yea!!! I am very excited about that!!! Within an hour of opening my present I was already telling him my plan for my next project! Granted, not all women would enjoy this kind of gift - and I understand that. But to me, cordless power sets my heart a-racing! He also gave me two books on tiling. I really like doing tile work (brought my wet saw with me to Arizona!), and have plans to do some tiling in the kitchen and the bathrooms here. Arizona is a great place to find all of the beautiful, decorative, Mexican tiles. We visited a tile store a couple of weeks ago; they not only had the decorative tiles, but also the bathroom sinks to match those tiles! Hmmmm! I see tiling in my future! In addition to the books and tools, he gave me a book on tape, a movie that he knows I like a lot, and a wallet that I described to him - and he picked out the perfect one! I must have been very good this year, and he did a great job shopping (considering he said he might end up shopping for me at the local Circle K gas station)! I didn't get him as many gifts, but I think he likes them. A new robe (he didn't bring his from Illinois), a sweater, and an IPod Nano! Now mind you, I spent two mornings loading music onto the IPod before giving it to him - roughly 20 CD's (more than 24 hours worth) of music! The stereo in his van has some sort of ability to play an IPod through it, also it will be great for him when he goes to the gym to work out. Up until now he has had to pick out the CD to listen to while working out - sometimes not finding the exact one that he was looking for. Now he can have all of his CD's on his IPod and listen to whatever he wants! It has 8G of storage, so he really can carry all of his CD's with him where ever he goes! Fun, but practical gifts, that we should get a lot of use out of!

We had hoped to go up to Kitt Peak to join a friend of ours there, this evening. The weather is not looking promising for that, however. Today is a perfect day for me to sleep - rainy/foggy/chilly - but may not be a good night to go observing. I'll get after Dean to get yesterday's pictures on here soon!

We hope that you had a wonderful holiday, and that 2009 holds nothing but happiness, health, and blessings more than you can count!

Wednesday, December 24, 2008

Another Traditional Christmas!

WooHoo - our 150th post since June - pretty good, I'd say! Here I am on Christmas Eve, and interestingly enough, I'm spending it exactly like last year's. After chasing the sunset behind Kitt Peak, I'm sitting home alone - listening to NPR's "Tinsel Tales. It is a great collection of Christmas stories from master storytellers from the radio archives, and I dare you to listen without shedding a tear or six! It can be found on the NPR website here. Melinda is off to the hospital to work tonight, but at least they get to share in a potluck holiday dinner tonight. I showed her the "secrets" of the chocolate cheesecake, so that is her contribution. And I got back from my sunset in time to provide a peck on the cheek.

Yes, I did chase the shadow of Kitt Peak up the road to Mount Lemmon north of Tucson. As told a couple weeks ago on this blog, the Observatory on Kitt Peak falls on one of the highway pulloffs a few days before and after solstice. Last week was absolutely miserable and cloudy/rainy and I didn't hold out much chance for tonight, but it cleared through the afternoon so I made the run up.

While not a new telescope, it was the first time I'd used this one for imaging, so had to modify it some to use my camera on it. The reason I'm using this one is that the focal length is just about perfect for getting the image of the sun just into the short dimension of the camera frame as illustrated here. This was taken while setting up - no sunspots at all to register - still just past minimum activity.

There was a lot of traffic on the road - people going down from a day in the snow, or to spend time with family in private cabins or lodges up at Summerhaven. The top of the mountain (over 9,000 feet elevation) had at least a foot of snow the last day or so, and one of the traditions is to shovel the top of your car or back of the truck with piles of snow so you can drive around Tucson with melting snow. A lot of them slowed when they spotted my telescope, but no one stopped to talk this year...

But luck wasn't with me this year. There was a narrow strip of clouds flowing north along the Baboquivari and Quinlan Mountains, and it appeared the Obseratory was in a cloudcap at times. Also seen through my telescope was the very rapid movement of clouds from south to north, as though the latest storm system was upon us, though the sky was mostly clear here in the Tucson Valley. Interestingly, after the sun had passed below this strip of cloud, you could see the shadow of the mountaintop and 4-meter telescope cast on the underside of the offending strip of cloud.
It was still a fun, peaceful trip, and a pretty sunset with the residual clouds around, but i would have been a lot happier with a "successful" (ie, clear) sunset. And now tomorrow (winter storm warning) is the last chance this observing season - as the sun moves north, it is out of my calibrated range of parking positions along the highway. Oh well, there is always next year - there is nothing like a tradition!

Tuesday, December 23, 2008

Nearly ready...

What a busy Christmas season this has been! Every day seems to be going quicker and quicker, with more and more to do! I have to admit, I think I have my shopping done. I know that Dean is still working on his. We managed to get the packages sent that needed to be sent, and our stack of received gifts is too large. One of my favorite things at Christmas is opening Christmas cards, and we've gotten a bunch of them this year! It's rare to get a hand written note from anyone, at any time other than Christmas, anymore. I think that's what makes each one so special. Someone sat, thought, and decided to write out a card to us - and put it in the mail. There's a lot of love in that action!
This year, as well as many before, I am working on Christmas Eve and Christmas Day. While most of the world is off of work celebrating with their families and friends, Nurses, Doctors, all hospital staff, Policemen, Firemen, and countless others around the world are going about their jobs as usual. It bothered me the first time or two that I had to work the holiday, but it doesn't anymore. Our patients don't want to be in the hospital (in my case, the parents of our patients don't want their babies to be in the NICU) - but there they are. As long as there are people there needing care (as well as people starving, or without jobs), then I can't complain about having to work. The years when I have the holiday off I appreciate, but I also appreciate being the first one to wish a tiny little baby "Merry First Christmas!!" Christmas is a time when we should all still have a bit of childlike wonderment and awe about us. Hopefully you haven't lost yours and you can appreciate what a joyous and beautiful season this is! I'm sure we'll add more to this blog before Christmas, but in case we don't.......enjoy this Christmas wish from Dean and I both!

Sunday, December 21, 2008

Phun With Photons!

One of the little optics/astro projects I've been playing with lately is to adapt an objective prism to my current camera setups. About 12 years ago, I had a nice flint chunk that I cut at a steep angle and polished both sides flat. When photographing through it, you could record the spectrum of an object with the light dispersed into the colors of the rainbow. This photo shows the setup - the prism goes up in front of the telephoto or small telescope - the wedge is about 2" thick at the base and almost down to nothing at the other end of the 4.5" diameter prism. In this case I'm shooting through it with the little Meade 80mm F/6 telescope.

In the previous incarnation of this device, I used 35mm cameras and film, but film was a poor detector. If you wanted to record colors, the film sensitivity often varied widely through the spectrum, totally dead at some wavelengths, overexposing some... Here with the Canon digital detectors I'm hoping to get some more uniform results. Another issue I faced with film still plagues me - the spectrum is scrunched up more in the red, so tends to get overexposed in that area. We'll see if Photoshop can help even out the display in that respect.

Eventually I want to use it to take some spectra of unusual stars and other astronomical objects, but for it's debut tonight I shot a distant high pressure sodium(HPS) streetlight, and an even more distant planet Venus (therefore, the sun spectrum reflected off Venus' clouds). The HPS light gives an emission spectrum - bright emission lines at discrete wavelengths that characterize a sodium spectrum. Astronomers take advantage of these discrete spectral signatures to identify elements in objects across the universe. Astronomy is one of the sciences where researchers never get to touch the objects they study - it is all from analysis of an object's light. The lower spectrum shows the absorption spectrum of the sun (reflected off Venus) - relatively cool gases in the sun's atmosphere absorb discrete wavelengths depending on the chemical elements. These absorption lines are a little diffuse and hard to see - I'm hoping to develop some better techniques with time. I thought there might be some interest in my early efforts...

Saturday, December 20, 2008

Disco Christmas

Send your own ElfYourself eCards

It was bound to happen....achoo!

Of course, when one member of the family has a cold or flu it tends to spread through the family. Now, instead of it being me who is sneezing and wheezing alone - Dean is joining in on the fun. He started with a bit of a sore throat a couple of days ago, sniffles yesterday, and stuffy nose this morning. He's a hale and hearty sort, hopefully he will not get too sick. I was off of work the past two nights - the NICU told me to take my bugs and go home. I'm much improved today and plan to return to work tonight. Dean is planning an observing/astrophotography session tonight, he should be able to still do that. He may have some pretty pictures to put on here in the next day or so!

The Christmas cards are coming and going on a daily basis here - as I'm sure they are at your home too! Every day we receive a card from someone we didn't have the address for, so we are continuing to send out cards daily. If you don't receive a card from us then it is probably because we don't have your address, but we wish you happy holidays all the same!

Thursday, December 18, 2008

Another Party!

Another party (tis the season!), this one a pot-luck holiday lunch at the Steward Observatory Mirror Lab, now in something like it's 15th year! One rarely gets to socialize much between the various crews of the Lab, so it was fun to relax, visit and check out the culinary skills from some unlikely sources! Thanks to all the efforts of the students in the front office for organizing the event. The best-dressed award went to Rich, here modeling his Christmas ornament shirt.

In this shot the buffet line is under attack and there were some great choices - a couple different kinds of chili and chicken gumbo, some interesting salads and more mainstream fare like ham and shrimp and some great side dishes. About the time all were seated, various managers reminded us of some of our accomplishments over the last year (LOTIS 6.5 meter collimator, a 1.6 meter off-axis solar telescope, the largest telescope secondary mirror in the world, another secondary for the LBT telescope, and some of the most precise test optics ever made for the upcoming GMT project) - really a lot of work got done last year. Upcoming projects were also covered (GMT, LSST, and a 6.5 meter for a Mexican telescope), and Roger Angel gave an update on his solar energy photovoltaic project (making electricity on the cheap). After all that morale-boosting, it was time for the dessert table - some killer stuff (including more of my chocolate cheesecake).

Star of the show was JJ's cute little boy. Now 7 months old, he put on quite the performance and may well be the next generation of employee to help us finish some of these big projects like the Giant Magellan Telescope!

Tuesday, December 16, 2008

Party Time!

Today is my birthday - number 55! I share the date with Beethoven, Leslie Stahl, Arthur C. Clarke, and William (Refrigerator) Perry, formerly of the Chicago Bears. Normally about this time of the month, some TAAA (astro-club) regulars would meet after newsletter collating and folding for pizza and beer at Old Chicago, so invited them plus a few other friends to join us for dinner.

A number were sick and were not able to attend, but we still had a good turnout. Besides the astro nerds (as we fondly refer to them), we also had our regular movie buddies, current and former cat/house sitters, and otherwise fine upstanding buddies. One of my favorite brews, Fat Tire Ale was on special, so a couple of those and some thick crust pizza and friends - whats not to love?! The first photo here is of the non-drinking side of the table - from the newsletter folding regulars. Melinda surprised me with a cake - and the staff guessed exactly right with 23 candles! I think that is what Melinda found so funny in this next photo...

It was a great birthday! Melinda was off today, so got to enjoy sleeping in a little while I went in to work for my half day. Melinda picked me up a few minutes early to meet Kris at a matinee - "Synechdoche, New York". It was my second time seeing it, and believe me, one needs to see it a couple times to pick up on everything. It is quite the movie and people seem to either love it with a passion or hate it equally fervently. I think I'm in the former, but it is not a feel-good movie with clear plotline and happy ending... When finally getting home, I got to open presents - I did well with everything I wanted - Melinda got me season 2 of "30 Rock" and a 500 GB USB drive to properly back up my computers. This is our first birthday since getting married in June and I've known for a while Melinda is a great gift-getter. She and her sisters always do great in picking out gifts. Another shot of the happy couple...

After our dinner and cake and stimulating conversation, we took a group picture, but I had turned off auto focus for a different shot, so we are a little fuzzy, but at least I know who everyone is! A great time was had by all. We decided next month, in lieu of newsletter folding (the TAAA newsletter is going electronic this month), we will be celebrating John and Thom's birthdays at Old Chicago...

Sunday, December 14, 2008

TAAA Holiday Party

The Tucson Amateur Astronomy Association (TAAA) held it's holiday party last night, hosted for the third year by Bill and Mary Lofquist. It was a great time and reasonably well attended by 45 or so members. We arrived fashionably late about 5:45 (listed start was 5pm) and man, we almost missed the food! And by the time we finished a lite plate I went back and managed to rescue the last 2 pieces of chocolate cheesecake that we had brought - those astronomers were starving! We ate with Bill Lofquist and Mike Terenzoni in the near darkness of Bill's observing area a little away from the festivities of the patio. The picture of Mike is a 10 second exposure!

The highlight of the evening was the "redistribution of astro-gear". Everyone was supposed to bring something from their astronomy collection for the raffle - we brought a book of which I had 2 copies. The big prize was a vintage 6" Dynascope from the 60s or 70s that member Clyde Plymate had restored. It was a beauty won by Wally, who chose to donate it to a local school, so it will see lots of use there. Also shown here is George Barber, who was perusing the raffle table before deciding on the wristwatch as his raffle prize.

Melinda was nursing a cold, so we didn't stay long in the cool evening air, but it was still nice to spend time with friends and come home with more that we left with - Melinda with her t-shirt from Starizona, me with a magazine full of pretty pictures...

Thursday, December 11, 2008

You know it's winter when...

How on earth do you know when it's winter in Tucson?!! That's a tricky question, really. While some people are dressing in sweaters and jackets (the ones who have lived here a long time), others (like me) are still wearing shorts and sandals on most days! The daytime temperatures are still creeping into the 70's during the day light hours, and tickling the 30's after dark. The Christmas decorations are going up around town, but there are still flowers (Oleander, Bougainvillea, Pansies, Petunias, etc.) blooming. How's a person to know??? This picture illustrates a sure sign of "winter is here, Christmas is approaching soon!

This is a statue of Padre Eusebio Kino, a very famous Catholic Priest who is credited with exploring the area of northern Mexico and Arizona. He was the first to discover that Baja California was not an island, and brought Christianity to the Native American tribes in the desert southwest. You can read his biographical information by clicking here. Padre Kino started (built by Native Americans) the San Xavier Mission, a very ornate and beautiful church that is still standing, still celebrating Mass, and still very much a vital part of the desert community in which it serves. Dean and I visited the San Xavier Mission in 2007. I was struck by the ornate beauty of the architecture and am hoping for another visit soon, to see the decorations for the holiday season! Padre Kino is also memorialized in Tucson with one of the major roadways being named Kino Parkway, and the statue (from the picture) being located at the entrance to Kino Parkway. And so, as we see in the first picture, Christmas can't be far off when we see that Padre Kino's trusty steed is wearing Santa hats on his ears!

Wednesday, December 10, 2008

Hump Day (Wednesday...get it? The middle of the week...)

Of course, this cartoon just fits in perfectly with the most recent posts of Dean! I like to think of this as what Starizona (the local favorite astronomy shop) was like - many, many, many years ago! This has been an interesting work week for me. I am finally, after a month, going through the general hospital orientation as well as the nursing department orientation. Hmmm, maybe it would have been good to go through these classes a month ago when I was first hired?? Better late than never is the motto here, I think! I am getting a lot out of the classes, I'll admit that. They're long days of sitting in a classroom, to be sure, but are full of valuable information. Our instructor is a 'ball of fire' Nurse who reallly makes learning fun. She always has an entertaining story to drive home the point, and who's wealth of experience is only rivaled by her sense of humor! One of the added bonuses of going through the orientation is getting to meet the other new hires to the hospital. There are, roughly, 30 people in my class - with only one other person who is new to the NICU. The rest are going to be working all over the hospital - ICU's, ER, Peds, the Cancer Center, and various Med-Surg floors. No one is a new graduate in this class, so the wealth of experience represented is staggering! It's a good group! While it's a long established fact that more and more men are joining the nursing field, I have only had the opportunity to work with one male over the past 30 years. I now have several male co-workers, and our orientation class is about half men. Since I've been doing these classes this week, that means getting up early every morning..... For those of you who know me, you know that I'm really not much of a morning person. I can fake it for a couple of days, but overall, it's torture! Since I'm having to get up early I've been trying to go to bed early. Every night it's been a little earlier, by tomorrow night I should be turning in about 7pm! With that in mind, I think I'm going to spend a little time watching TV with Dean, and then turn in.....

Tuesday, December 9, 2008

Large Synoptic Survey Telescope (LSST)

I know there has been a lot of astronomy postings lately, but with the return to Tucson a month ago and my being back to work at the Mirror Lab, they seem to come more naturally than "normal" posts!

Anyway, the Tucson Amateur Astronomy Association had their monthly meeting last Friday, and the invited speaker was Victor Krabbendam, project manager for the LSST telescope and site. It was a great talk - I love the technical side of projects and Victor did a good job of explaining the details as finely as you wanted them!

This is a really cool project! I invite you to go to their home page and check out the specs. In short, they are building a 3 mirror wide-field 8.4 meter diameter telescope (Hmmm, wonder who is making that for them?), combined with a 3.2 GIGApixel (!) camera 64cm diameter providing a 3.5 degree field of view (about 7 widths of the full moon), it reaches 24th magnitude in a 15 second exposure! The camera, weighing nearly a ton and a half (including corrective lenses) will generate a peak data flow of 3 Gbytes/second, totalling an estimated 20-30 Tbytes of data per night. The plan is to cover the entire sky in 3 nights, each field being imaged twice over some interval, looking for things that move or vary in brightness. It is expected to generate 100,000 alerts/night of things that change!

This telescope is different in that there are no astronomers per se - all data is made public as soon as it is taken. Most people do not know that Hubble data, for instance, is the property of the astronomer for 6 months to a year before release to public domain. You can sit at your home computer, watching the data streaming out. Or you can subscribe to whatever alerts you would like to see (asteroids, variable stars, ???) and be the first to see the images after the computer. Interestingly, Victor was saying that in the early part of the evening the data will be close to "live", but even with supercomputers and fiber cables connecting the United States to South America (Observatory will be in Chile), it won't keep up to the data flow, needing about 24 hours per night of data reduction.

The telescope mirror, made by the Mirror Lab in Tucson (Yea!) will be the first large mirror that will have 2 curvatures on the primary (the primary curvature, plus the R3 tertiary surface as well). It should be a challenging project, particularly with the strong aspheric of the tertiary surface...

The mirror, in fact, has been under construction for some time. The mold for the lightweight primary was constructed the end of 2007 (you can see the two curvatures in the cores here), finished in January, and the glass loaded in March for the 29 March casting. The oven was opened in July, and as of today, the mold material is being removed using high-pressure water similar to that of a carwash. The fellows that do that job wear wetsuits in the 100% humidity and forced-air respirators to minimize inhalation of the refractory material. That task will be finished tomorrow, and after a final rinse and allowing it to dry out over the Christmas break, it will be inspected in January and delivered to the polishing lab the end of January, 2009 to start work on the backplate.

So I'll get a chance to get my hands on it early in '09 when the casting crew finishes up. Melinda and I are only here to 1 May or so, and it seems realistic to finish diamond generating and get into the grinding and perhaps polishing before then. In any case, with LSST and GMT going strong, it will be a busy winter and spring!

Sunday, December 7, 2008

Planning A Field Trip!

There are no shortage of astronomical field trips in southern Arizona, but one of them has a long history with me! Back in the fall of '87 I had an opportunity to use the little-used 16" Schmidt telescope on Mount Bigelow north of Tucson (since converted to a 26" and used to search for asteroids and comets for the Catalina Sky Survey) for nearly daily observations of bright comet Bradfield. I noticed in my frequent trips up the mountain that there existed a spot where the sun would set behind the silhouette of Kitt Peak National Observatory. I made it a goal to accomplish that feat. Turns out that near winter solstice, when the sun moves little from day to day, that there is a pullout along the highway where it can easily be done. And fortunately, there are two brief windows a couple days before and after solstice that provide alternates in case of bad weather.

The pullout is on the outside of a hairpin turn just past milepost 9 on the Mount Lemmon Highway. I've set up there several times the last few years, continuing to refine the best sun position and observing position. It turns out that just a few yards on the ground makes a noticeable change in the sun's position against the mountain. The photo shows my setup along the side of the road in December of 2006.

Here is the best shot from that sequence taken on the afternoon of 24 December, 2006. I was using eyepiece projection with a William Optics 11cm F/7 refractor to get the image size correct, and unfortunately, the seeing was terrible, and likely my focus was also a bit off. In any case, it was a successful observation, and in fact, I made an animated GIF movie of the frames, taken every 4 seconds. It can be seen by clicking here(about a 2MB download).

Always looking for a better result, last year ('07) I lead a group from the astronomy club to capture it. Unfortunately, on the Saturday chosen, it was far enough south that we had to significantly change our position away from the pullout to the next one, and it missed the profile of the mountaintop for a perfect alignment, so I went the next day again, 24 December, 2007 and got good results again, but the sun is riding low on the profile, so would prefer it a little further north in the future. The photo is from that observation. Note the change in scale from above - this time I was using the William Optics scope with a 1.4X converter, with sharper, but smaller image.

It is a beautiful view of the observatory from that spot, looking over the Tucson valley, nearly 60 miles from Kitt Peak. Seen in silhouette from the left are the Vacuum and McMath-Pierce solar telescopes, the 84", 36", and 3.5 meter WIYN telescopes, the old 50" dome, the tiny blip of the Visitor Center's 20" and the 24" Schmidt telescope near the profile center, then the 72" and 36" Spacewatch telescopes, the 90" telescope, and finally the 4-meter telescope at far right.

As for helpful hints should you make the trip, practice before the trip to make sure you have correct image scale and filtration. I use an old Thousand Oaks filter with a little higher transmission for photography which helps keep exposures short since with the sun on the horizon it can be a lot fainter than when overhead. It also helps to arrive early well before sunset to align on Kitt Peak before the sun forward scattering off 60 miles of turbulent air makes it impossible (I suggest arriving 45 minutes before sunset). If you get there early enough, you can use the sun's glint from the 4-meter to help you focus! As for dates, from the north end of the pullout, you can see last year's image was taken with the sun as far south as could be and still span from Solar Vacuum to the 4-meter in one photo. There was only a single frame, taken every 4 seconds that showed that. So the minimum declination should be -23.405. This year, the sun will be too far south on the evenings of the 18th through the 23rd. So the "preferred" dates for 2008 are the evenings of December 16th and 17th as the sun is moving south towards solstice, then again on the 24th and 25th as it moves north again (ideal dates are 17th and 24th). Unfortunately, they are all midweek dates and do not suit folks with day jobs, but it is the best I can do! Those without families can do Christmas eve or Christmas day attempts... Or another alternative is to grab an observatory shot and a sun shot and use Photoshop to combine them (not recommended)! Questions or comments, e-mail me (click on my name at upper right of blog page)