Saturday, May 21, 2016

How an astronomer counted stars and became a traveler

1977: My mother, relieved that her prodigal son had returned in one piece from a
six-week trip all over Mexico & Guatemala. Roger's Pub was operated by a
Canadian expat in Panajachel, Guatemala.

From the introduction to Counting Stars at Forty Below, expanded and adapted for this blog—

Mexico, as it was in the 1970s—and isn’t now—was my Paris. With Mexicans, Europeans, and Americans I celebrated life and the journey, which took on qualities of a pilgrimage in which every moment was a moveable feast and every place was a shrine. I was in a

My first passages into Mexico were through astronomy. For reasons I never fully understood, at Christmas of my fourth year I received a small reflector telescope and some books about astronomy. At four a telescope was more than I could handle, though I do remember one afternoon when the moon happened to be high in the sky, and I was looking at it through my telescope. As NASA began sending men into space, I watched TV to see the launches and the recoveries. I got up sometimes in the middle of the night to see meteor showers. The name shower conjures an expectation of seeing stones falling from space into the atmosphere at the rate rain falls in a shower, but that doesn't usually happen. Usually a meteor shower produces a meteor visible to the naked eye of only one per minute. Yet I do have this memory of going out onto the front porch in the middle of the night, and despite a thick layer of clouds, I could see dozens meteors raining down in the sky continually. This amazing vision was likely a dream, but it was nevertheless formative.

The stars really began for me when I was 12. My next-door neighbor friend, Ray, and I took up star charts and sat in lawn chairs at night, and it took us two or three nights of holding these pocket-sized books up in the air over our heads as we searched for a correlation. Yet finally a great epiphany like angel dust drifted down and I saw at once that the little charts we had were drawn on cramped little pocketbook pages, while the stars were writ large against the night sky. You might be familiar with a little star cluster, easily visible with the naked eye in the summer, called the Pleiades—the seven sisters. To me, the cluster resembles a little champagne glass in the sky for its shape, like stemmed glassware, and for its sparkly tight-knit bunch of stars. Well, that little patch of stars had the scale that the tiny books had led me to expect all constellations would have. But in that epiphanic moment I suddenly saw that the constellations are scattered not in reluctant, rare deposits, like the champagne poured by a stingy wine steward at a poor man's wedding, but in great sweeping motions of arms held at arm's length. It was a great "Aha!" moment, and having achieved it, all the landmarks of the summer sky fell into place. We found Cygnus, the swan, and nearby Lyra, the harp, with diamond like Vega, crown jewel of the summer sky; Taurus the bull with its red eye, Altair; and in the far south a scorpion prowls the Milky Way even as a rising archer, Sagittarius, seeks to chase it away.

Before long we acquired binoculars and more sophisticated star charts that led us to abundant treasures of open and globular star clusters scattered throughout the Milky Way, and a pair of binoculars is all that's needed to see the ballet of Jupiter's four brightest moons as they circle the planet. The more we saw, the more we looked, and the more we looked, the more equipment we needed. We appealed to our parents and by the next Christmas we each had modest refractor telescopes that Sears sold in their catalogs, so now we could watch not just Jupiter's moons coming round the planet as they come, but also the planet itself with its bands and tempestuous red spot.

Ray and I naturally joined the local astronomy club when we spotted one of its meeting notices in the paper. This club was a meeting ground between professional astronomers of the University of Texas, which has one of the world's leading astronomy departments, and local amateur astronomers. Astronomy is one of the few professions in which amateurs contribute on a par with the professionals. Although information technology may soon change this, to date more comets have been discovered by amateurs than by professionals. There are far more amateurs than professionals, and the pros have only so many observatories, but the amateurs are an army of eyes observing every far flung of the sky every night. If something unusual happens, it's likely they're going to see it first. So astronomy totally lacks the disdain for laymen that you see in other fields. Indeed, astronomers often wander through crowds of amateurs like itinerant preachers seeking their aid and evangelizing for their particular specialty because they need a dozen telescopes pointed at the same place at the same time.

At monthly meetings a speaker, often from the universe, talked about his field and his work. I learned the basic concepts underlying the specific and general theories of relativity from a cosmologist who was so smart that he could express his ideas in clear language to be understood by all.

An entomologist—an insect scientist—spoke to us about a module that he prepared for Skylab, a Saturn V booster left over from the Apollo program. NASA used the extra booster as an early form of International Space Station and stuffed it with all sorts of experiments that were sent into orbit along with a few astronauts to run all the experiments. The entomologist had an experiment designed to see how wasps would react to weightlessness. I don't remember much of what he learned about wasps, but there are two things that stuck with me. He paid a visit to the factory where his module for the wasps was being fabricated, and he was horrified to discover that they were dipping the plastic walls of the module into a solution of water and detergent. The two things I remember: (1) detergent is an extremely lethal insecticide and (2) once a surface, especially plastic, comes in contact with detergent, it is impossible to remove it: traces will always remain. The module would have been a death trap for the wasps had he not stumbled into the dipping. For these reasons, there are certain things, like wine glasses and beer mugs, that I never expose to detergent. And when I have Tide laundry pods in the garage, I'm sure to shut the container tight because the roaches are drawn by Tide's perfume but killed by the detergent. The big plastic Tide container is like a giant roach trap, and I don't like to pick my pods out from a roach morgue.

If you've ever spent any time in academia, you will know that universities and their departments play a competitive game of politics around policy and the acquisition of people for their departments. One of UT's coups was the acquisition of French astronomer Gérard de Vaucouleurs (1918, Paris—1995, Austin). De Vaucouleurs came and spoke to us at one of the astronomy club's meetings. Perhaps he remembered that his interest in astronomy began when he too was an amateur. For the membership, he was a kind of Magical Mystery Tour of astronomers in that you had to be really into astronomy, an astronomaniac, to appreciate the value of the speaker we had that month. He was, among astronomers, globally known. He had cut his teeth on Mars by drawing extraordinary pictures of the red planet while looking at it through powerful telescopes. This was back in the day when sometimes the human eye and hand with a sketch pad captured more information than the rudimentary astrophotography of the time. De Vaucouleurs moved on to the study of galaxies, where he contributed even more of his careful and methodical work. He revised Edwin Hubble's catalog of galaxies (yes, the same Hubble for whom the HST is named). This catalog of galaxies is key to understanding not just how galaxies work, but the nature of the universe of the whole. The famed Red Shift of galaxies—a slight shift in the colors of galaxies that indicates they are receding from us—is the central piece of evidence that the universe is expanding. The catalog's measures of the apparent size, brightness, and red shift of a galaxy—which can then be converted to the energy, distance, and velocity of the galaxy—are key parameters to the understanding of the size and expansion of the universe. De Vaucoleurs also originated the idea that galactic clusters gathered into clusters of clusters, or superclusters, and this idea is still alive and well.

The speaker programming was relatively egalitarian. We even had one of our members, who had co-founded an organization whose mission was to spread the idea that gravity was a push and not a pull. A planet like the earth somehow summoned a lot of pushing that held the objects on it down and the satellites around it in orbit. It was a moot point of course. Gravity worked just the same.

For someone like me who would attend UT after high school, the astronomy club was an exciting anteroom with all sorts of things going on. Indeed, this connection with UT emboldened me to loiter about the Astronomy Department, where I foisted my questions upon hapless graduate students who were too kind to turn me away. One afternoon a grad student spent over an hour explaining to me how a star maintained a brightly burning thermonuclear reaction in a neatly symmetrical sphere because it attained an equilibrium between gravitational pressure inward and radiation pressure (that constant thermonuclear explosion) outward. There is a natural symmetry to the thermonuclear fire in a star, especially when you compare it to the dangerous little fires that humans make when they play with fusion and fision—it's as if, in the case of a star, this is what the fire is for, while when we play with bombs or

My friend Ray was not bound for academia, and he gradually wandered away from the astronomy club as I drifted deeper into it. I was helped along with generous opportunities that rarely happen at any other stage of life. One of the amateur astronomers in the club was a graduate student in computer science with a job in the astronomy department. I was still in high school when I bumped into him one day as he carried a large tray of punch cards from the computation center back to his office. I asked him how computer programs worked, and he told me to buy a FORTRAN primer and let me use his account to access UT's CDC 6400/6600 tandem mainframes. So I was a lucky kid: the IBM PC would not exist for another ten years, but I already had access to computers and taught myself how to program.

This photograph shows the phenomenon known as Baily's Beads, during which
sunlight shines through valleys on the limb of the moon and is blocked by mountains.
Photographed from Jiuquan, Gansu, China, during an eclipse on August 1, 2008.
Photograph by James West. As published at Flickr, included through Creative Commons license 2.0.

Not long after I began programming computers, an astronomer named David Dunham showed up at a meeting of the club straight off the highway. He had finished his term of service with the Air Force and was now going to work at UT Astronomy. Dunham's area of interest was the limb of the moon, meaning the outer edges. You can't look at these mountains and valleys on the edge the way you can look at the topography around the crater Tycho, for example, because at the limb the surface of the moon is turned ninety degrees away from earth. There are indirect ways of learning about the topography on the edge of the moon. In the last moments before totality in a solar eclipse, sunlight shows through the valleys and is blocked by mountains—this creates a beading of light around the limb of the moon called Baily's Beads.

The more arcane way to see the effect of the lunar limb's topography happens during what's called a grazing occultation. But to understand what a grazing occultation is, you first need to understand what a plain occultation is. An occultation, generally speaking, is when the moon, in the course of its orbit, passes in front of a star and hides it from view. Because of the geometry involved, the passage of the moon in front of a star varies considerably according to where you are standing on the earth. An easier way to think of this is that the moon casts a shadow with respect to the star in question. That shadow is a circle on the surface of the earth, and if you are standing inside the circle, the moon is blocking your view of that star. The moon is orbiting the earth, which means the shadow circle is not stationary but moving rapidly across the surface of the earth in the same way that there is a circular shadow of totality during a solar eclipse. And just as a total solar eclipse has a path across the earth, so an occultation too follows such a path.

If I am standing dead center in the path of a star's shadow as cast by the moon, I will see the thickest part of the moon pass in front of my star, and roughly an hour later, the star will pop out the other side, none the less for wear and oblivious that part of a small planet was briefly blocked from seeing it by an even smaller moon. But what if I'm standing on one of the two edges of the shadow path? Suddenly the irregularities along the limb of the moon—which otherwise appears like a perfect arc—come into play. Where there are mountains passing in front of the star, it is hidden, but in the valleys the star is visible. So David Dunham would plot the shadow path for an occultation, and he would find a long straight road perpendicular to the edge of the path. Along that road he would place amateur astronomers at intervals of about a tenth of a mile. The observer farthest into the path would likely see the star disappear altogether until the occultation was over, and the observer farthest out of the path might not see an occultation at all. But the observers in between might see a spectacularly elaborate series of disappearances and reappearances.

For the sake of simplicity, the pink line represents a moving star
behind a stationary moon. Of course the reverse is true—the star is relatively
stationary while the moon moves past it—but this diagram still shows
the important effect: the star disappears and reappears according
to the topography on the limb of the moon.
So by the time I became a student at UT, I was hanging out at Dr Dunham's office. One day I overheard two astronomers across the hall saying they needed an undergraduate to work for them, so I introduced myself and landed my first paid programming job.

When I was 19, I went on a magical expedition to see an annular eclipse in Puerto Escondido on the Pacific coast in the state of Oaxaca, Mexico. David Dunham organized the expedition because he wanted to see whether it is possible to observe Baily's Beads during an annular eclipse. Astronomically, it was an interesting trip. But the discovery of an entirely different culture within a few hundred miles of where I lived completely enchanted me and turned my world upside down. I went as an astronomer, but I came back as a traveler.

This shift from astronomer to traveler serves almost as a metaphor for what happened when I reached university. Going in I felt confident that I would major in physics as preparation for graduate school in astronomy—there was no undergraduate astronomy major at that time—the depth and breadth of courses on that campus made me feel like the proverbial kid in a store full of sweets. I wanted to study everything. I changed majors nearly every semester for a while. Yet no matter what else I was taking, I also took English classes, which indeed became my major once the wheel stopped spinning round and round.

Neither of my parents went to college, so they had no council to offer me on the advantage of studying something now to completion and studying other things later. And of course when I walk into a department and boldly declare that this is what I want to study, this is the discipline that I want to practice for the rest of my life, the departmental counselor sees me as a customer, so they're hardly going to discourage me from changing majors, even if it's for the tenth time. My broad shift in college from Natural Sciences to Humanities foreshadows my shift later in life from programming computers to going back, finishing my degree in English summa cum mora (with greatest delay), and getting an MFA in writing—after which I traveled around the world teaching English. That thirty-year pattern of programming then shifting to writing echoes exactly what happened to my interests during the seven years or so that I first hung out and occasionally studied at UT.

On top of that, whenever I had time, and a little money, and sometimes I went when I had neither, I went back to Mexico. Each trip was a variation on a three-chord progression: Mexico City, Oaxaca, Puerto Escondido. Mexico City's modern Metro system laced together the historical sites, art museums and galleries, and restaurants. Oaxaca allowed me to decompress in a colonial setting and read books by Carlos Castaneda and John Irving, hip reading at the time. And Puerto Escondido had the most tranquil beach I had ever seen. On one trip I did not withdraw from school until I came back; and on another I did not withdraw at all, and I had the grade-point average to prove it.

No matter where I went, I counted stars, but most of the time it was not at -40° F. (or -40° C.—they're the same). I look up into the tropical skies to count, glimpse at the noctiluca speckling the beach, and feel completely at home as gravity lays me down in the sand. On these trips, the terroir on the tongue comprises travel as much as walking. Among the intricately carved ruins in the jungle at Palenque, I partook of the Mayan sacrament, the sacred psilocybin mushroom, and there I learned to see. Education stretched my mind one way, but travel stretched it in another.

One time I ran out of money just north of Veracruz and hitch-hiked back to the U.S., but everyone I met was kind and caring: I did not starve—indeed people should now and then make food a matter of trust—and I made it home. This kindness, like people passing me hand by hand in the air over their heads at a concert, formed my faith in the cultures south of the American border. Just inside the U.S., I stood with my thumb out to hitch a ride at the bitter end of a highway with my long hair whipping the breeze. A trucker passed me by, and although he did not give me a ride, he threw a joint that landed precisely between my feet. When I returned to Austin I was deeply tanned, unburdened of the sulkiness of responsibility, effervescent with poetry, and illuminated with the dancing flame that draws people the way that the moon draws moths. In 1978, this Mexican period produced a chapbook, The Poetics of Quetzalcoatl, most of which is reproduced in Counting Stars at Forty Below. Most of all, though, my adventures had shaped me into a traveler who would eventually circumnavigate the globe, and that would have a lifelong love affair with Latin America.