Observatory 8, 9, and 10: Mt. Graham International Observatories

It’s been over a year since I was in Arizona and made my way to Mt. Graham. That’s just ridiculous. I don’t understand how it’s possible. So, I guess I better get back to the work of recording my experiences before my memories have entirely evaporated. I’m hoping it’s not too late already. Fortunately, you can find some of what I did with my pictures and comments over >here<.

You have to make a reservation to visit the >Mt. Graham International Observatories< through the East Arizona College Discovery Park, and the tours are infrequent. Well, they are supposed to be regularly on the weekends, but they had the Fry forest fire in June 2017 that had made it a bit dicey to go up the mountain for some time. In fact, they didn’t do any tours for about a year. I was able to make a reservation for Saturday, August 25, two days after my trip to >Kitt Peak<. It is on the order of two hours to the east of Tucson near Safford, and the tour was at 9:30 a.m. So I was up and at ’em at an uncharacteristically early 6:30. I got one of the worst meals of my trip, a fast food breakfast on the way out of town, and down the road I went. It was actually a very pleasant drive through some beautiful country, mountains giving way to plateaus.

Started from the bottom…

The Discovery Park is a small campus of about 4 buildings of various sizes housing, among other things, a small observatory and the museum where we met for the tour. If I remember, the tour was $40, which included the gas to get up the mountain, lunch, probably some permits, and a bit to keep the program going. Permits, because there is an endangered red squirrel on the mountain that is protected, so not just anyone can go gallivanting about on Mt. Graham. In fact, after a brief introduction, anyone going on the tour has to sign a form promising not to harass the squirrels under pain of federal penalties. Okay, MtG red squirrels, be cool; do your thing. (As it turned out we didn’t see a one of them.)

The three observatories on the tour are the Heinrich Hertz Submillimeter Radio Telescope, the Vatican Advanced Technology Telescope (VATT, and yes, that Vatican, the Vatican), and the Large Binocular Telescope (LBT). The latter is by some reckoning the largest optical telescope in the world at the moment, but more on that later.

Movin’ on up…

There were about a dozen people there for the tour, enough for two vans. The trip up the mountain takes an hour and a half to go a linear 27 miles. However, that 27 miles includes a 5600-foot vertical ascent and 109 switchbacks. Our two docents were very knowledgeable about the environment on the mountain, and the gentleman driving, whose name escapes me, gave a running description of the different zones to the three or four of us in our van. There are five distinct climate zones as you ascend from the plain to the summit, and oddly, these are the only bits I wrote about in my journals for the entire trip to Mt. Graham. (That whole journal thing didn’t work out quite the way I imagined, but then, what does?) For those who like to keep score my notes record something like this:

  1. Lower Sonoran desert at the base, 3400′ elevation, 3-12″ annual rainfall; ocotillo (a spiky, alien-looking succulent shrub) grows here
  2. Upper Sonoran at 5000′; manzanita, juniper, oak
    • highest density of black bears in the southwest on the mountain
  3. at 6000′ – ash, walnut, pine; 10-20″ rain;
    • Heliograph Point used in the 1800s to transmit messages by mirror from NM to CA
  4. Transition zone from 6500′-8000′; Douglas fir, ash, sycamore, black walnut; 18-28″ rain
    • One of the switchbacks is called Cadillac Curve – an old couple drove off the cliff at a switchback because they were confused by the arrow signs above and below point in to the vertex of the curve. A tree stopped the car, and no one was injured. The signage was changed so you could only see one or the other at one time. Also, they were driving a Lincoln and not a Cadillac.
    • the mountain in national forest land; some cabins, no power grid
  5. Canadian zone from 8000′-9500′; Douglas fir, white and ponderosa pine, aspen; wild flowers, columbine, Indian paint brush
    • Arrow tree – there’s a tree along the road that hunters shoot at; if they hit it, it’s good luck for the hunt! So the poor old tree is spiky with arrows.
    • Naturally, clouds started settling in as we ascended.
    • We ran out of pavement 7 miles from our destination
    • They used to get 200″ snow pack up here, but lately it’s been more like 50″
    • Lots of fresh washouts and alluvia from monsoon rains and fire-cleared mud
    • Our guide said over management of the forest has allowed dense growth of trees that naturally would be about 100′ apart but now grow right beside each other, allowing for easy spread of fire and disease
  6. Hudsonian zone from 9500′-11,500′; 10-12′ of snow

They brought the mirrors for the Large Binocular Telescope, each 8.5 meters in diameter, up this same road with all its switchbacks. It took them three days to drive the 29 miles.

Now we here…

We stopped at a national parks area with restrooms (yay!) and a picnic shelter where we had lunch – a Subway combo meal. As you may see in my pictures, my chips had puffed up to ridiculous proportions with the change in altitude and fairly exploded when I tried to open them. It was really loud! Several of us were becoming aware of the altitude, too, as we walked around, sensing a distinct lack of air pressure. Not dizzy or anything, just feeling the need from time to time to gulp what air there was.

After lunch we piled back in the vans and headed to the MGIO site proper. The three observatories stand side by side by side, maybe 100 meters from each other. The VATT to the left, the LBT to the right and the Submillimeter in the middle. There was ample evidence of the recent forest fire, which as it turns out came within a few dozen meters of the Submillimeter observatory. This came to light when someone asked, “Why is the observatory all streaked pink like that?” It turns out that when they were fighting the fire, they airdropped slurry on the site and actually hit the observatory. They were successful in saving all three observatories, thank goodness.

Okay, so I notice I’m starting to repeat the things I wrote as comments in my photo album, and that seems a little silly. So please take the time to click over there to see the pics and read what I wrote there, and I’ll see if I can give some other different impressions here.

The three facilities were similar in some ways and unique in others. They all have control rooms that are pretty much a series of computer stations. They all have a certain industrialism to them, by which I mean there is at least some area that is like a machine shop with lots of tools, instruments, wires, spare parts, and a smell of oil and solvents in the air. The Vatican observatory, while it has such things, felt more balanced with the residential area we saw, which includes thick carpet, comfy chairs, and bookshelves. It felt homier. I suppose that’s not really so, but that was my impression. The LBT is the most industrial because it is an enormous machine with hundreds of smaller mechanical subsystems. All three have a hand in some revolutionary technology. The VATT and LBT are among the first to have spin cast, honeycomb mirrors from the UA Caris Mirror Lab. The Submillimeter dish, as I added to my photo comments, is part of the Event Horizon Telescope, a virtual radio array the size of the earth that is taking pictures of black hole environments.

I was disappointed with the interpretation we got from the docent leading the tour, especially at the Submillimeter dish. I think it was maybe her first time giving the tour, but she really had no idea how radio astronomy works. I knew because I had just been at the Green Bank Observatory a couple weeks before. It’s a fascinating field of astronomy that not a lot of people are familiar with, and while she gave it the old college try, as they used to say, but jeez. Here’s an example. With radio astronomy they cool the receivers and electronics because otherwise they produce radio frequency noise that interferes with the signals they are trying to detect. Our docent, though, said something like, “they cool the receivers to freeze the radio signals coming in so they can read them.” I mean, come on.

The Different Scopes

The Hertz Submillimeter

The 10-meter radio dish was cool and all, but it wasn’t jaw dropping since I had climbed up the GBT and had used the GBO 20-meter dish for fun. They have very different missions, of course, with the Submillimeter dish doing high-energy radio astronomy, while the Green Bank dishes are more relaxed energy, so to speak. I would have liked to see the shutters open and the dish in action, but the monsoon was in effect.

Speaking of the monsoon, as we made our way from the radio observatory to the VATT the clouds were moving in, fast and hard. I took some pictures and vids where you can see how fast. The sky was half clouded when we went in the VATT facility, and by the time we came out, maybe 45 minutes later, we were socked in. By the time we were done at the LBT, the temperature had dropped by 20 degrees and the wind was whipping through. Later still, when we got back to the Discovery Center the sky was just mostly cloudy with patches of blue. Very dynamic weather that time of year.

The VATT

Back to the telescopes, the VATT was, again, pretty cool for being the first of its kind, with the 1.8-meter (6 foot) prototype spin casting mirror. It’s a fast, open cage, Cassegrain-style reflector on a fork mount. In that regard, it is not unlike the 2.1-meter scope at Kitt Peak. It does some work in infrared, which is pretty uncommon and made it somewhat unique on my list. And I mean, if someone gave me a 1.8m scope, I’d be delighted, but otherwise, in many ways it was just another reflector. So I found that one thing with a pilgrimage like this is that not everything is going to blow your socks off, because you’ve seen something like it already.

The LBT

I had not, however, and would not for the rest of the pilgrimage, see anything quite like the Large Binocular Telescope. This is a truly impressive piece of equipment. There was a fellow who worked there who took over the tour guide duties (thankfully!) and did a great job. The first thing we got to see was the vacuum chamber that is used to re-aluminize the mirrors. This in itself was enormous. Next we got to see the wheel mechanisms that rotate the part of the building that serves as the azimuth bearing for the telescope. The steel wheels rest on a steel track, sort of like train wheels, and are close to three feet in diameter. Several of these wheels are in each of four “bogies” that include the motors that drive them and various electronics systems to coordinate their movement together and safety systems, etc. These bogies are about 8 feet tall and 20 feet long. We also got to see the control room, which is pretty much like the other control rooms, only more so, with about a dozen computer stations.

Finally, we made it under the dome, as it were (except that it’s actually more of a box), to see the instrument, which is colossal. An 8.5-meter mirror is the size of a swimming pool. (Remember those mirrors they were making at the >U of A mirror lab<, polished smooth to a millionth of an inch?) Surround that with a rigid cell to hold it and the detectors you’ll use. Then add the cage and supporting structure to hold the secondary mirror or other detectors at the right distance to get your focus. Then double all that. Then add enough supporting structure to hold both sets rigidly so there is no relative displacement between them to thousands of an inch tolerance. Then put it all on a mount so you can tip it up and down and turn it in any direction, and smoothly enough not to disturb the alignment of the two systems.

Okay, this one is jaw dropping! In fact, I was so impressed by it that I forgot to take a selfie with it. Imagine!

Odds and Ends

I haven’t written much about the people I met on my travels. This is unfortunate, as I didn’t write about many of them in my journal, either, and they are starting to vanish from my memory. I do remember meeting a family of four from the U.K. at the LBT. The parents were maybe in their 40s with two teenagers. I don’t remember their whole story, but they were on a nerd tour, sort of like mine, although, if I recall correctly it was maybe space stuff and outdoor stuff in the southwest U.S. Ugh, I wish I’d written it down, because it was pretty cool.

After we got back down, I drove through the nearby town of Safford to see if there was anywhere interesting to eat or shop. As seems to be typical of small western towns, the streets are wide and few. There were several places that might have been interesting, but for whatever reason (maybe I just wasn’t that hungry yet), I decided not to stop. I headed back to Tucson, about a two-hour drive. When I got there, I was faced with essentially the same problem of where to eat. My apartment was not well equipped, so eating out was the norm. I wanted something local, southwestern, not fancy, quick, and still open. After a few passes up and down the main drags, I settled on La Salsa Fresh Mexican Grill. This turned out to be a fast order burrito place with counter service, which was a little less than I hoped for, but I was really tired, and it was getting late. As you can see in the pictures, I ordered something called La Grande and had the nerve to be surprised that it was big! No sides except some chips. They had a salsa bar, so I tried a couple. I don’t remember much about them. The food was good enough that I ate it all, in spite of my not being especially hungry. I remember the manager being helpful when I came in and when I ordered. There were several other patrons, well after normal dinner time. All this notwithstanding, apparently the place has gone under and been replaced by Famous Dave’s BBQ. Too bad. I liked the idea of a salsa bar.

It was a long, long day with lots of astro-adventure and fresh air. I made it back to the apartment and was done.