Frank N. Bash:
Director of McDonald Observatory
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With a jovial, sunny personality, a shock of white hair, and a voice and delivery made for radio, Frank Bash has served since 1989 as director of McDonald Observatory, the astronomy complex operated by The University of Texas at Austin out in the remote Davis Mountains of West Texas. For a man who publishes papers with titles like "Implications of Collisionally-Supported Giant Molecular Clouds for Spiral Galactic Structure and Massive Star Formation" and the even catchier "CO J = 3-2 Observations of M51," Bash's most astonishing characteristic is his ability to explain the mind-boggling concepts of space to the rest of us. In his classroom or office, the incomprehensible cosmos becomes a gallery of down-home images: cars on highways, pancakes, basketballs, farmers gathering rainwater with buckets, and raisin cakes rising in ovens. A native of Medford in southern Oregon, Bash earned his bachelor's degree from Willamette University in Salem, Oregon; his master's from Harvard; and his doctorate from the University of Virginia. A well-known and widely published specialist in radio astronomy, Bash joined the University of Texas faculty in 1969. In 1979, he was a visiting professor at Leiden University, the Netherlands, and at Cambridge University. He served as chairman of the Department of Astronomy from 1982-86, and in 1985 he was named the Frank N. Edmonds Regents Professor of Astronomy. As a researcher, Bash is interested in large-scale star formation processes in spiral galaxies. He has won numerous teaching awards and was named to UTMost magazine's Teaching Excellence Hall of Fame in 1984. 
He spends most of his time in Austin, where he can more easily promote the observatory, and travels to McDonald Observatory in the Davis Mountains for about a week every two months, except in the fall, when he teaches astronomy to 230 freshmen. (Observatory superintendent Mark Adams has full-time charge of the facility's daily operation.) If McDonald is a monastery of science, Bash's parsonage there is perhaps the sweetest perk of any job in Texas: a house at the base made of volcanic rock, perched on a cliff side with a 100-mile view to the east. Bash has led the effort to expand the public-outreach programs of McDonald Observatory. These programs include the observatory's Visitors' Center; StarDate, the syndicated two-minute radio show heard by millions each day in English, Spanish (Universo), and German (Sternzeit); and a bimonthly magazine of the same name. Were he to retire today, Bash's most spectacular legacy would be the construction of the 11-meter Hobby-Eberly Telescope at McDonald. But he is not retiring today. And as he gazes out his office window on the 15th story of Robert Lee Moore Hall on the UT campus, he is dreaming big again, very big. . . . At what point did you know that you wanted to be an astronomer? Back when I was an undergraduate major in physics, and I was a senior thinking about what I wanted to do with my life and what sort of a career I wanted to make out of physics. I had a professor who was interested in astronomy, though he was teaching physics. He had a telescope, and we'd go out and look at all this, and I just decided without ever having a course in astronomy that I wanted to be an astronomer. So I applied to the graduate school at Harvard in astronomy and got accepted, and that was it. That's not so uncommon in astronomy, because an awful lot of kids that go to graduate school in astronomy have undergraduate degrees in physics. That's almost preferred. That fall, I worked as a teaching assistant in freshman astronomy there. I had never had an astronomy course! So here I was, the teaching assistant in this course, grading papers. I was about one week ahead of the kids, franticly going through the book. It was hilarious. Does astronomy attract a certain type of person? Astronomers are physicists who study things away from the earth but also understand that the night may be cloudy, equipment may break, that your ability to understand that distant galaxy depends entirely on the light that comes from it. You'll never be able to go there to get a sample. I've always thought that astronomers were an odd combination of physicists and forest rangers, walking through the forest and sort of overwhelmed by it all, the trees are so big and clustered together. The universe is so vast and there are so many stars and so many galaxies and so few astronomers and telescopes that it's just kind of overwhelming. Like an emergency room physician, you develop a side of your personality that can understand the majesty of it all. But then there's the clinical side where you can deal with it all. Astronomers are also very evangelistic. They love to talk about it, love to teach it. You don't have any problem getting people here to teach the freshman astronomy class. They love it. As you said, you spend your life studying these places you could never go to. But if you could, where would you go? 
I have never had much interest in space travel, and I've never honestly understood why. You learn pretty early on in school that the speed of light is the fastest speed you can travel, and given the distances out in space, there's no practical way you could travel anywhere very interesting. You could go to the planets near the earth; even so, in a NASA-launched space craft, you're talking years and years to get to Mars. But most of us work way out beyond that. The other interesting thing is that we're in the Milky Way Galaxy, which is this giant pancake of 100 billion stars. When you stand outside you can see the band of light across the sky, which is caused by the fact that you're in this pancake, and you're looking at it edge-on. So here we are in the Milky Way, and there's a major problem because there's dust in the disk of the Milky Way and that prevents us from seeing what it's like. So it would be better to be a little away from it so you could look down on it from the outside and study its shape and how it works. You're almost better off not being there to be able to study it. Also, it's fun to do it this way. It makes it more challenging. Your specialty is radio astronomy. Can you give a thumbnail sketch of how that differs from traditional astronomy? It wasn't known until 70 years ago or so that, as well as visible light coming from stars, there are things in the sky that radiate radio waves very strongly. Radio waves, it turns out, are a form of light, just with a longer wavelength. It was always supposed that stars would radiate radio waves because anything that's hot radiates light and radio waves together, but there wouldn't be anything particularly interesting or novel about that. Bell Labs was investigating radio static because future telephone calls across the ocean were likely to be over the radio in those days; satellites weren't even thought about. And there was all kinds of static. One of their guys discovered that there were objects in the sky that were very much stronger radio emitters than stars are. As the subject developed, aided by the electronic developments of the Second World War, there were objects discovered that were extremely strong sources of radio waves, like supernovae, stars that have exploded with their remnants splashed all over the neighborhood. The fact that the objects radiated radio waves gave us insight into a whole new class of objects that we hadn't properly appreciated before. It also led to discoveries that there are these enormous black holes in the centers of galaxies, into which matter is spiraling. As they spiral, they get hot and radiate radio waves very strongly. Often radio waves are symptomatic of a disturbance, some explosion or some problem that's occurred. It shows you celestial violence. But I ended up not focusing on violence but on the birth of stars. When stars form, they form in dense clouds of gas. And in those clouds of gas we've discovered there are natural processes that make chemicals in these clouds--simple chemicals like carbon monoxide, water molecules, alcohol. And those simple chemicals radiate characteristic radio waves, and even though the cloud is very dark because it has dust in it, the radio waves penetrate the dust and so we can study the interior of these star-forming clouds by looking at the radio waves coming out. And if chemistry is going on in those clouds, as a precursor to star formation, and if those chemicals are there when planets form, then the chemicals that might build up and make amino acids and proteins are naturally present when planets form around stars, which would suggest that the chemical process that results in life may not be that rare. What is the farthest thing you have observed? 
The farthest things that we are able to look at are these things called quasars. They were initially found because they are strong sources of radio waves. The reason they have the odd name they do [from quas(i-stell)ar (radio source)] is that radio astronomers were able to pinpoint directions in the sky from which strong radio waves were coming and then give those coordinates to a regular astronomer to take a photograph of that point. And as we got better and better at pinpointing the position, we finally discovered that there was this thing that looked like a star right at the right position. They turn out to be galaxies that are very far away. They are galaxies with tremendously violent events going on in their centers in the vicinity of black holes, which are sucking material in. This disk around a black hole is very luminous and very violent, shouting at us with radio signals. Those quasars could be about 13.5 billion light years away, about as far away as you could see any object. How far you can see is a function of how big the telescope is and how good the location is, but it also depends on the luminosity of the object you're looking at. If it's a very powerful light bulb you can see it a long way away. The nice things about quasars is they're very powerful light bulbs. The Hubble Space Telescope can't see normal galaxies as far away as 13.5 billion light years, but it sees galaxies farther away than anybody's ever seen galaxies before. A normal galaxy is not nearly as luminous as a quasar. Space telescopes or earthbound. What's the future of astronomy? 
The Hubble Space Telescope, of course, has the great advantage that it's above the atmosphere so it doesn't have to look through all this air. That gives you two things. The view is much less disturbed by the air. Second, you can look at parts of the spectrum where the earth's atmosphere is opaque, for example, the ultraviolet. The disadvantage is that it cost about $2 billion, and the mirror is only about 90 inches across. So it's a relatively small telescope, even by McDonald standards. Its light-gathering ability is limited by the size of its mirror. It's the same problem as a farmer wanting to catch rain in a storm. The amount of rain you can catch depends on the area at the top of your bucket. At $16.5 million with instruments, [McDonald Observatory's new] Hobby-Eberly Telescope [HET] is tremendously cheaper and enormously larger than the Hubble. We can gather a lot more light, but we have to look through the atmosphere. The U.S. is now seriously planning a successor telescope to Hubble called the New Generation Space Telescope, the size of which is not yet determined, but the biggest one I've heard discussed is still considerably smaller than the HET. God only knows what that's going to cost. Development of computers and rapid sensing on the earth now has some extremely interesting possibilities. It looks as though, at least over small patches of the sky, that you can correct for the blurring effects of the atmosphere. Believe it or not, in real time, a telescope with the equipment attached to it can measure distortions introduced by the atmosphere and you have a mirror in the light path, underneath which are little pushers that can make little bumps and valleys. So you sense the distorting effects of the atmosphere, you introduce into this mirror the reverse effects, and then you shine the light off that mirror, and it corrects for the atmosphere. Is that amazing? You're changing the distortion about 30 times a second. Now, it's expensive, but compared to $2 billion or $6 billion dollars, it's not expensive. So some of the reasons for launching a telescope into space are being overcome by technology. Once that technology is developed, we might be able to put it on the Hobby-Eberly Telescope. That does not solve the fact that the earth's atmosphere is opaque in the ultraviolet, so there's still a reason for launching space telescopes. What about doing something along the lines of the Hobby-Eberly piecemeal on a space station? Is that the future? That's the future if you can afford it. At the time that the U.S. launched astronauts to walk around on the moon, this was a national priority, and compared to what was then the gross national product, that was an enormously expensive project. The U.S., especially now that the Cold War has been won, has not seemed to be interested in spending that amount of money on projects like that any more. It's not that you couldn't conceivably put the Hobby-Eberly Telescope on the space station. It's that, as far as one can tell, the political structure doesn't want to spend that money. What is the practical value of astronomy, or is it purely the satisfaction of curiosity? That's an extremely good question. In the job I've got, I really think about those things a lot, because I'm the guy that has to justify to various funders--private individuals, foundations, state government, federal government--the expense that they're putting into this. A lot of my colleagues have wanted to justify expenditures in astronomy based on practical benefits because you would hope that science produces things that involve society and produce better consumer goods and so on. And they have tried to make those arguments about astronomy, but in my opinion those arguments have always been kind of phony. I have never been at all impressed by those arguments. The part of justification for doing astronomy that I have appreciated more and more, as I have stood in the Visitors' Center at McDonald, is that I think that society sees astronomers as its explorers. One now understands the surface of the earth--an oceanographer heard me say this one time and said "but we don't understand the depths of the oceans," and in fact we don't understand all there is about DNA either--but in terms of the kind of geographical exploring that we can really understand in our hearts we have explored the earth. However, I think human beings are built with the need to explore. The reason parents bring their kids to McDonald Observatory is in some sense showing them what the explorers are doing. Now, how much money that's worth, I think is very arguable. It suggests that society is willing to spend taxpayer money on a certain amount of this, but how much is less clear. 
Astronomy is one of those subjects that kids really enjoy. You can go out and look at the moon. You don't have to buy any equipment. You don't have to buy a tennis racket. You can think about the fact that that thing up there is Mars, and Mars is a planet and circles the sun and so on. We are building all over this country, but especially in this state, an economy that depends more and more on high tech, more and more on software, more and more on engineers and technicians. We used to have a natural resource-dependent economy, and now we don't. The price of oil has almost no effect on the economy of this state anymore in terms of taxpayer revenue. And so what we at McDonald are increasingly doing is helping teachers use astronomy in the grade schools to excite kids about careers in science and technology. Not to create a whole lot of astronomers, because the world doesn't need a whole lot of astronomers, but to get those kids interested in careers as engineers, technicians, physicians, and so on, and it is absolutely amazing how many people in those scientific careers are there because of an initial interest in astronomy. UT President Larry Faulkner is one of them. We've just broken ground on a new Visitors' Center at McDonald Observatory, with construction starting today [September 2000]. We've got three radio shows in English, Spanish, and German, and we publish a magazine in addition to the school programs--about $1 million a year worth of public outreach and education programs. Yet surely there are some practical aspects to astronomy? There absolutely are. The way perhaps to think about it is that astronomers themselves are a small enough number of people that it's very hard for an industry to spring up that does nothing but serve astronomy. But astronomy has driven the development of charge-couple devices. When you buy a home video camera, and it says that inside is a CCD, those are light-sensitive chips, which, when light shines on the back of the chip, put out digital information about the image. The CCD developments were stimulated by the needs of astronomers, who acted as smart customers helping develop these devices. The astronomy market is very small, but the other markets that develop are broader. If you could ask a genie one question about the universe, what would it be? 
Right at the top of the list: In the last 20 years we have discovered that perhaps 90 percent of matter in the universe is invisible. By the nature of astronomy, we are forced to look at those things that are luminous, shining out light. But we have discovered that the motions at the outsides of galaxies, for example, are clearly being influenced by stuff that we can't see. It's got to be there, because the gravity of it is influencing the motions of those stars. Right? It's invisible in the sense that no light comes from it, but its gravitational influence is being felt by those stars. And so, one of the great mysteries is, what is that stuff? Where did it come from? What is it?! Ninety percent of the stuff in the universe is stuff whose composition, whose nature we don't understand. It's really weird! What is dark matter? We don't know. That's a biggie. Do we know where the center of the universe is? There is no such thing. There's no center. By the nature of the assumptions you've got to make to study cosmology, there can't be a center. It's very odd. Then where did the Big Bang happen? After a lot of conjecture and speculation and theorizing, pretty much all working astronomers believe in this so-called Big Bang picture, in which the universe started out really small at some time roughly 15 billion years ago. It exploded. All of this stuff came out of it. But the thing that's so hard for us to picture is, the explosion of something that started the size of a dot, all the matter and all the energy, but in addition, all the space was in there. And when the thing exploded, not only did all this matter and energy come out of this explosion, but all the space came out of it too. So we were in there. And the concept of what was outside the dot before the dot exploded, it turns out is a non-concept because all the space was inside there too. Imponderable stuff. And so the subject of the cosmology, the origin of the universe, and all that kind of stuff is a kind of mixture of science and philosophy, a very interesting subject and very hard to come to grips with. So does that also mean that the universe has no limit? Clearly if this is an event that took place, and things are traveling outward, there is an outer limit. So wouldn't you just measure the distance from one outer limit to the opposite outer limit, divide it in half, and that's where it happened? 
All we can say is that observationally, we can't see any edge. That is, as far as we can look in all directions, galaxies stretch out as far as we can see. And it turns out also, that what we can see is influenced by how light travels in the presence of gravity, which is described by Einstein's Theory of General Relativity. So for example, if the universe is "closed"--a certain amount of material in the universe--then tonight, if you shine a beam of light up into the sky, the beam of light curves inside the universe, and travels around and hits you in the back of the head, eventually. So there is a picture in which there are no boundaries. It's like the surface of a basketball. If you were an ant crawling on a basketball, you'd never find an edge. You come back around on yourself. Our ability to study the universe also depends on how light travels in this thing, and the so-called topology of space, the curvature of space inside the universe. It's tricky. Can we not even understand where we are in the expansion of the universe? Well, we look at distant galaxies and find them expanding away from us. And the more distant the galaxy, the faster it expands away from us, and we find that to be true in all directions. But it's also the case that anybody in any galaxy would see the same thing that we see. Imagine making a cake in which there are raisins in the batter. And so the cake sits in the oven and the cake starts to rise and all the raisins get farther apart from each other. So if you stand on one of the raisins, then you'd find the more distant the raisin, the faster it's moving away from you. But that's seen by every raisin. So the fact that we see everything expanding away from us does not suggest that we're the center at all. But couldn't you measure the speed of the outer raisin and the speed of several other raisins and triangulate and speculate that we're a little farther away from the center or a little closer to the center? No. Everybody sees the same thing. Imagine going out here to the upper deck of I-35 and lining up a bunch of cars, and giving each driver instructions that when the gun fires, I want you to go 60 miles an hour; you're going to go 50 miles an hour; you're going to go 40 miles an hour; you're going to go 0 miles an hour; and you're going to back up 10 miles an hour. Gun fires. Everybody starts driving. The cars are all spread out after an hour, and no matter which car you stand on, what you'll see is that the car nearest to you is the one whose speed is smallest relative to you. If you're a car going 30 miles per hour, the car going 0 miles per hour is separating from you at 30 miles per hour, just like the car going 60 miles per hour. If I plot up the distances and velocities, I can't tell where the starting line is. I have no way to tell. So no, there's no way to know where it started. So you're saying this is something we can never know? That's right. Well, that's not very satisfying. I guess I'll have to go to graduate school. (Laughs) A lot of students come into graduate school wanting to study cosmology because of the set of the ultimate questions. It turns out to be very difficult, very slippery, and a lot turn out losing interest. Do you own a telescope? Yeah. A 2.4-inch telescope that I got about the time I graduated from college and that I haven't looked through in 30 years now. If you were to stumble into $100 million that had to be used for the observatory, what would you do with it? We've been talking to Cornell University for some time. Cornell has always been intrigued by the design of the Hobby-Eberly Telescope. The Arecibo, Puerto Rico, Radio Telescope has the same kind of design, and Cornell runs that, so we're sort of telescopic brothers in a sense. They've wanted to do a project with us, and there's this possibility of a telescope two or three times bigger than the Hobby-Eberly, built jointly with Cornell, on this 20,000-foot mountaintop in northern Chile--probably the best remaining site for astronomy on the surface of the earth. It's a place where it's never rained in recorded history. It looks like you're on the moon. And now with modern technology, in spite of the fact that it'll be expensive to build a telescope there, it's much less expensive than building one in space. The quality of the academic program in astronomy--the quality of the students and faculty you can attract--has an awful lot to do with what sort of research opportunities there are. If you had a significant piece of a telescope on the best site left on the surface of the earth, then your astronomy program is definitely going to benefit. My job is to make this [The University of Texas at Austin] the best astronomy program in the country. The department chair's, Chris Sneden's, is the same as mine. So at McDonald, there is logically nowhere to go from the HET? You're maxed out. 
Yes. The nice thing about McDonald and the reason we put the HET there, is, of course, that all the infrastructure is there, which made it a lot less expensive. But in addition, the skies are very dark. Had the same thing happened at McDonald that happened at Palomar in California, where the suburbs of nearby cities just grew and grew, and the city lights just made the night skies impossibly bright, we couldn't possibly have put the HET there. But the neighbors out there are so cooperative, and the population density is so low that the skies are dark. Ultimately, the problem is that McDonald is only about 7,000 feet in elevation, so there's an awful lot of atmosphere above you still, and the best sites on the earth are going to be sites that are high enough that there's less atmosphere above you, and where it's very difficult to breathe. Now, it was hard enough getting out to McDonald. I can't imagine what would be involved in a deal like this. There are people down there who work in mines, up to these elevations, believe it or not, and there are people who can work at those altitudes; they'd have to be the people who build the telescope. And now with modern communication, the Internet and so on, the picture is that we would operate it remotely. There would be a maintenance staff that would have to go up there and fix stuff, but astronomers would not go there. We would maybe have a local headquarters in some city on the sea coast of northern Chile where we would have warehouses and where people could drive their cars up to the mountaintop. But the typical astronomer using that telescope would sit in his office and look at the data over the Internet. The Internet has made a profound change. Even for the HET, we've got partners all over the world, and the data from the HET is sent to those astronomers over the Internet. How important is the public to the observatory's mission? 
The public is vital to the observatory's mission because the public pays for it. The money that we spend at McDonald is taxpayer money. The state of Texas is extremely unusual in appropriating money for scientific research, and so the money that operates McDonald Observatory is directly appropriated by the legislature. Public support is vital. Without it we wouldn't possibly exist. And so we are very, very, very sensitive both to the issue of value for money--What kind of contribution are we making to pay the public back for the money it gives us?--and we're also very sensitive with our visitor program, in telling the public how we spend our money. What are we doing here? Unlike the old-fashioned view where an observatory was closed with fences and locked gates and big signs that said "Keep Away," we have exactly the opposite view. We're open 362 days a year for visitors. We have tours all the time. We have a new visitors' center being built and star parties all the time. And how has the public's interest changed over the years? Something like 80 percent of the science stories in newspapers in the United States are about astronomy. Whereas astronomy gets less than 5 percent of funding for all research topics. So there's a tremendously disproportionate interest on the part of the public in astronomical developments. People want to go to McDonald Observatory and find out what we're doing. There's an enormous interest in astronomy, and I'd have to say that it just continues to grow. I've never seen any slacking in interest. And I love it. Interview conducted by Avrel Seale,
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