Not Quite an Observatory: The University of Arizona Mirror Lab

My first tour in Arizona was the >University of Arizona Richard F. Caris Mirror Lab<, and you can see my pictures and comments at >this link.<

By this point I was becoming aware of the number of places I was visiting that pushed the limits of technology, knowledge, and skill for the sake of science. The Yerkes 40″ is the physical limit for refracting telescopes. LIGO is the most precise measuring instrument ever built. At this lab they craft mirrors that are smooth to one one-millionth of an inch. Such things are staggering to contemplate, at least for me.

While this isn’t an observatory, this lab is making observatories possible. They are making mirrors for the Giant Magellan Telescope being built in Chile, and they made the mirrors for the two optical telescopes on Mount Graham, which we will get to in a couple posts. >Here is a link< to a time lapse video, taken from inside the kiln, of the glass melting in the making of one of the mirrors. As far as I know, this is the only place doing work like this. There are other mirror labs, but nothing making mirrors this big.

This is also about the time I brought to consciousness a thought I’d had when I was in college working in a wind tunnel lab. Science smells like oil. We tend to think of science as being clean and pristine and airtight, or at least I do, but when you go to these facilities, the labs and the observatories, they smell industrial and oily. Big science in the real world, not your classroom stuff, is much more earthy than we see in the movies, with lubrication, and metalwork, and miles of wire, and countless boxes and drawers of spare parts. It’s not all theory and math and formulas. You need those, of course, but then you have to make them work in physical space.

That’s part of why I think we should focus much more on science, and space science especially, as a national economic priority. Science needs all manner of workers to make it happen. You need theorists, sure, but also technicians and skilled labor to put the parts together; fabricators, tool and die makers, welders and builders making the parts and things that hold the parts; construction workers building the work places and labs; plumbers, electricians, and painters to make the spaces workable; maintenance crews to keep it all in shape; administrators and clerical workers to organize it all; then you have to feed all those folks and provide housing and retail for them. Every big science project should mean work for hundreds or thousands of people with all manner of skills and all for the betterment of humanity. Decent work for decent wages should mean better opportunity and improved economic justice in communities. Better work and pay should mean decreased crime and need for social services. I know I’m an idealist, but am I missing something here?

But I digress. Here they make mirrors the size of swimming pools so we can see the farthest stars.

 

Observatory 6: LIGO

I’ve been keeping up better with recording my journey with my photos, which are now living at my Google account since I have an Android phone. Say what you will about the evil digital empires, it is convenient.

Any way, going way back to Louisiana and the LIGO facility, you can see my pictures and comments at >this link.<

Short form: >LIGO< stands for Laser Interferometry Gravitational wave Observatory, which consists of two campuses, one in Hanford, WA, and the other in Livingston, LA, where I went. It is an instrument that measures the distortion of spacetime by waves created by the interaction of supermassive bodies like neutron stars and black holes. It is a whole new way of looking at the universe, it is incredibly precise, and it is remarkably expensive. New technology is like that. We don’t know yet what the practical applications of all this will be, but I bet it will be cool.

LIGO Livingston is open to the public one day a month through their educational center. They have a very good collection of interactive displays aimed at kids and novices to help explain the science they do there. The staff are knowledgeable and friendly. Tours don’t really show you much of the actual instrument, as it is pretty inaccessible being encased in evacuated steel tubes surrounded by evacuated concrete tunnels. So you get to see the control room and the outside of the tunnels and a prototype of some of the pieces of the instrument. But somehow, that was adequate for me.

It is mind bending to think about waves in spacetime. They aren’t waves inside space but space itself waving. That means when the waves pass over the earth, the whole planet, your home, your chair, your body are all stretched and squeezed. You don’t notice because the effect is minuscule, but it happens nevertheless.

The universe is a weirder place than you would imagine.

 

Observatory 1: Green Bank, part 2

Radio astronomy is a fascinating branch of science, in part because it is in some ways very different from optical astronomy. Since we can’t see radio, you can observe and gather your data anytime, day or night. The dishes that act as telescopes get basically one-pixel resolution. So where your phone or camera has several megapixels resolution, the largest radio dishes basically act as a single point, if I understand correctly. It is by panning the dish across an object that you are able to form a picture from it. But there is also a great deal to be learned from radio data without even making it into a picture. For example, different chemical elements give off unique radio frequency signatures. Hydrogen emits radio at 21 cm wavelength, which translates to a frequency of 1420.4 MHz. Since hydrogen is the most abundant element in the galaxy and the universe, you might think that trying to map it would be a little crazy. But an interesting thing happens when you observe a span around that 1420.4 MHz. Because of the nature of space and time and electromagnetic waves, we can detect if the hydrogen being observed is moving toward us or away from us, and how fast it is coming or going, and how far away it is from us. That’s a lot of information! So mapping the hydrogen in the galaxy is like making a navigational map of rivers, harbors, lakes, and seas. It gives you an idea in 3-D of how the galaxy is built and how it is moving and changing.

At the Green Bank Star Quest, I got to do some of that kind of science directly! After a workshop on the basics of radio astronomy (where I learned some of the above), we were given the opportunity to use the 20-meter dish to look at … anything we wanted! A couple others in the class and I looked at two significant radio sources, Cass-A (supernova remnant) and Orion-A (star-forming region). Later we added the Owl Nebula, the moon, Mercury, and a variety of other objects. Some were strong radio sources and others less so, and Mercury not at all, which is weird. I still have a lot to learn about what our scans mean, but it was amazing to be able to run a world-class instrument.

I also got to use the 40-foot radio dish at GBO. It is, I think, the smallest of the active dishes at GBO, but let me tell you, 40 feet is not a small dish! About seven of me end to end would fit across it. This dish is also rather historic in that, as I am led to understand, it was used by Frank Drake for the first SETI (search for extraterrestrial intelligence) experiments in the 1950s and 60s, Project Ozma. This is a transit dish, which means it is always pointed along the N-S meridian, rotating up and down but not side to side. There is a control room in a below ground bunker that looks like a science office from the 1960s. A couple stacks of electronic equipment stand in one corner, the instruments appearing to be of 1980s vintage. By means of analog dials and switches and a digital frequency selector and a tractor-feed data record with two pens, one can collect actual science data by aiming the telescope, selecting a frequency range, and interpreting the graph on the paper strip. It is wildly old school science, and it was a blast! Three of us worked together to get some data under the tutelage of our guide Sophie, but I got to take home the data. I followed some directions on a hand-out and found that the blob of hydrogen we investigated near the center of the galaxy was moving away from earth at (if I recall correctly, as I don’t have it here with me) 48 km/sec. How cool is that?

Along with experiences in several other lectures and workshops, I found that I was just having the best time being a science student again. It gave me a thrill, not only to be learning from professional scientists, but also to do actual science. To be transparent, I also got a thrill from being a good student, knowing or figuring answers to questions ahead of others in the class. Yes, I like being an overachieving, curve-busting, teacher’s pet and always have.

But really, it’s the thrill of the science.

Observatory 1: Green Bank

I spent four days and nights at the Green Bank Observatory (GBO) in Green Bank, WV, July 11-15. A local astronomy club has hosted the Green Bank Star Quest there for fifteen years. It is a very well run event, and I had a ball.

Now some star parties are just camping at a dark site, observing the sky at night and (as I’m told) either sleeping or drinking during the day. Not at GBSQ! First, there’s a bunk house and cafeteria, so no camping required, although you can if you want. Second, they had tours, speakers, and workshops lined up from 9am to 8pm every day, so no reason to be bored. These were really good, too! I learned so much about radio astronomy, “multiple messenger” astronomical discoveries (finding things out through various lines of inquiry), and even astronomy history! The evening keynote speakers were all very enthusiastic, interesting, and engaging on their various topics. I met some new friends as well as spending time with a college bud of mine. In fact, when I registered I was told I am now part of the Star Quest family!

There is more to write about this week’s experiences than I can manage tonight, but I want to get one thought out there. The principle scientist at GBO, Dr. Jay Lockman, was the keynote speaker for Thursday night. He spoke about his experience in developing one of the Great Courses for The Teaching Company on radio astronomy. He told us about the rather grueling process of writing, editing, and filming the course, about some of the history of radio astronomy that he learned himself in developing the class, and about his own radio research, which ironically ended up on the cutting room floor, all of which was quite interesting. His recent research is on the enormous bubbles of gas and dust that have been found to be expanding from the center of the Milky Way above and below the central core, and how, by tracking neutral hydrogen in those areas, some theories as to their nature and flow have been developed. This led my friend Bruce to ask in the Q&A, “As fascinating as this is, how do you answer those who say (and always there are those who say), ‘What is the point of all this? What difference does any of this make? How does this help anyone, or me in particular?'” Dr. Lockman asked Bruce what his answer is first, to which Bruce said, “My answer is, ‘What is the point of a baby?'” which I thought was insightful.

Dr. Lockman, acknowledged Bruce’s idea but went on to say, <paraphrase> “Of course we who do such things know about the intrinsic value of science and of any sort of knowledge, and we can talk about that and about how we may someday find practical applications to all these discoveries. Further, we can talk about the relatively tiny financial investment that we make in science and the vast returns we receive on that investment. But frankly, I am tired of trying to convince people of that. If it isn’t obvious, it is very difficult to get someone to understand it. What I have come to use as an answer instead is that people are interested in these things. I spend a great deal of my time telling conferences full of people like yourselves about this, and they are excited by it. We have 50,000 visitors a year that come through this facility, because they care about science and want to learn things. So it makes a difference because there are people who care about it.” </paraphrase>

This blew me away, and it continues to provide thought fodder for me. It is a great prophetic statement in its justification of something precious and its repudiation of the inherent repudiation in the question. Let’s look at other cases. We might ask, what is the point of professional sports? What good does it do anyone? What is the point of popular music? What is the point of photography, or sculpture, or quilting? What is the point of fishing, or hiking, or boating? What is the point of collecting antiques or beer cans or paperweights or dolls? None of these things has any practical justification, either, but people pour large amounts of time, money, and energy into all of them and more. People make careers around most if not all of these things, too. Why should science, which produces so much more value to the world than, say, football, be held up for scorn as a waste of time and money? And, if the value of science is found in that humans like it and find meaning and pleasure in it, then so, too, the value of all those other things as well, at least to the extent to which they are not harmful to human wellbeing.

Humans do what humans do. Some of us love science. Let’s give thanks for that.