2010 Thesis Excerpts
James Scott Berdahl, Morning Light: The Secret History of the Tagish Lake Fireball
Joshua Feblowitz,Computer, MD
Amanda Martinez, The Unfinished Miracle: How Plastics Came to be Lost at Sea
Morgan Sherburne,Distant Harvest: The Production and Price of Organic Food
Nidhi Subbaraman, Why We Sing: An Ode to Our Musical Origins
Morning Light: The Secret History of the Tagish Lake Fireball
by James Scott Berdahl
Jim Brook pushed south in his green ’81 Chevy. The sun had disappeared behind the mountains of the western shoreline, and twilight was settling in. The ice was getting rougher now too; in the north it had been smooth and solid, but here there were patches of crusted snow that collapsed beneath his tires, and strange shapes, scalloped by the winds, that morphed with the passing of his headlights. A few drifts of snow stretched across the frozen lake, and he picked up his speed to ram through them. It was some sixty kilometers back up the valley to where he’d left the road. If he got stuck, he was on his own.
At first he didn’t really see them. Hoar frost and uneven patches of ice rushed past the truck, and he dismissed a few as tricks of shadow and light. But one was unmistakable, a dark form perched on top of a smooth patch of crusted white snow. It was too far out on the lake for it to have made it there from shore, and there were no tracks leading up to it. He knew immediately what it was, but there was no way he could have realized its significance. He slowed to a stop, put his truck into neutral, and stepped out onto the ice.
The darkest months of winter are a quiet time in the Yukon Territory. As the northern hemisphere leans away from the sun, shadows rise up from the valleys, and they engulf the frozen landscape in their calm. Snowfalls mute the forests and cover the murmuring of mountain streams. In the crisp chill of a clear night the stars are almost audible.
Most of the people live in Whitehorse, a city of about 20,000 on the banks of the Yukon River. Weekday mornings, the arteries into town fill with traffic. The red taillights of car after car stretch like rubies on a string across the dips and around the curves of the Alaska Highway as residents commute in to the downtown core. The sun appears later, skirting the peaks of the southern horizon, as if to check on the place before heading south again. In the evenings, Whitehorse exhales. Streams of headlights spill back out, carrying residents into the clusters of country residential homes that surround the city. There’s a rhythm to the season that the people have grown accustomed to.
But on the morning of January 18, 2000, just after a bright waxing moon disappeared behind the western horizon, that rhythm was interrupted. For about ten seconds, the night sky flickered with powerful blasts of artificial daylight. A white light appeared in the north and skimmed south across the sky, exploding in a series of violent flashes. Commuters stopped on the highways and traffic halted in the streets. People stepped out of their vehicles and stared up in amazement. Others were indoors; they saw the landscape outside light up through kitchen, bedroom and office windows, or they saw shadows and sudden blue highlights shifting through their homes, and they hurried outside to see what was happening. In every town people filed into the streets, and they gazed up at the radiant contrail that hung in the sky. It lingered for more than a half hour, gleaming amidst the starry sky in the light of a yet unrisen sun, slowly losing its shape to the winds of the upper atmosphere.
The phone calls started immediately. With the contrail still bright, eyewitnesses called friends; they called the authorities; they called scientists; they called the media. Authorities and scientists and media all called each other, trying to nail down what had just happened. The phone lines at the local radio station of the Canadian Broadcasting Corporation filled with witnesses anxious to share their stories, and it was up to Peter Novak’s calm baritone to mediate discussion on his daily program, The Valley Voice.
“At about 8:45 this morning, two brilliant flashes lit up the sky over the southern Yukon. And it was brilliance; some people say it was as brilliant as a photo flash or very intense lightning.”
Reports poured in from around the Territory. “I’m still kind of rubbing my eyes, Peter—it was the most blinding thing that I have ever experienced…” “It was like a fluorescent light that was going out…” “…a pinky-peachy colour, and then blue, and then white…” “…coming into two or three pieces…” “…I thought I was having a stroke…” “I heard a big kaboom, and the windows on my house shook…” “…my heart didn’t start beating for another two, three minutes…” “…of all the places in the world a fellow could be…”
A single question resounded through the south of the Territory, something along the lines of, “What the hell was that?”
In response to the confusion, Novak turned to Jeremy Tatum, an astronomer from the University of Victoria. From the start of the interview, Tatum left little room for ambiguity. “What you’ve had this morning is a particularly large and exciting fireball,” he said. Though many accounts described the object as having passed just overhead, the fact that they were pouring in from towns separated by hundreds of kilometers told Tatum that the fireball had in fact been very high, burning brightly in the upper atmosphere.
“Basically, a fireball is an extremely bright meteor,” he explained. “A meteor—that’s the flash of light you see in the sky.” A shooting star. Most are tiny grains of dust or rock fragments that burn up completely in the upper atmosphere, seen perhaps by a handful of stargazers, or by nobody at all. “If a stone lands on the ground, that is called a meteorite.”
From the intense explosions at the end of the fireball’s path, Tatum knew there was little chance anything had survived, and he said as much. But he kept his bases covered. “Bear in mind that if you find it, you’re in possession of something which is very valuable. … If it’s on crown land, and you don’t have to dig it up, then the finder is the owner.”
In a Territory full of prospectors and adventurers, this undoubtedly caught the ears of many listeners. Novak sensed the response.
“I remember the old days in the Yukon when we used to hunt for gold,” he said.
“Well, this is more valuable,” said Tatum.
A bow slides along a violin string: a perfect C sharp. The string vibrates. Pressure waves ripple through the surrounding air.
Some reach your ear. They lap against your eardrum, and an attached three-bone hinge passively flexes in turn. As the hinge moves, it pumps a thin, bone membrane. It’s called the oval window, but you can’t see through it.
The rap on the window from the tiny hinge creates a violent fluid wave. It courses along two, thirty-millimeter long tubes inside the tight curves of a snail shell shaped bone. That bone is the cochlea. Just as on the violin string, the wave creates forceful vibrations along the tubes’ walls. The C sharp trembles not far from the cochlea’s entrance; a lower-pitched open G vibrates further in the bone’s spiraled depths.
These ringing walls push against a smaller but vital third tube, sandwiched between the other two. Inside, “hair cells” stand at attention in rows, a quiet field. The vibrating walls bear down on them and they bend—just slightly—like deflecting the top of the Eiffel Tower half an inch.
But it is enough. The deflection of the hair cell triggers a current at its base. Here, the mechanical becomes electrical. Neurons at the hair’s base call out. The brain’s auditory nerve listens. You hear.
At least most people do. About three out of every thousand Americans are “functionally deaf.” Hearing is connection—a series of intimately tied causes and effects: an electric current created by fluid waves, set in motion by a tiny hinge, pumped by pressure waves in air. “Functionally deaf” is, medically speaking, disconnected.
Some are born this way. According to the American Speech-Language-Hearing Association, genetics accounts for almost fifty percent of children born deaf. Other causes include ear infections, otoxic medications, meningitis, measles, otitis media (an inflammation of the inner ear), premature birth, maternal diabetes, and infections such as rubella.
Most deafness is sensorineural—meaning that the disconnect happens somewhere in the sound’s delivery from inside the cochlea to the brain. This could mean damaged auditory nerves, but most often the hair cells are the cause. Instead of standing in an orderly field, the cells knot and tangle. They never respond to the cochlea’s rolling waves, and never trigger an electrical signal sent to the auditory nerve.
A cochlear implant bypasses these damaged cells. During a three-hour procedure, a surgeon expertly places the device in the inner ear, coiling a string of electrodes inside the cochlea’s spiral tract. The implant can help patients with profound hearing loss, but, since the surgery destroys all residual hearing, implantation is irreversible.
In 1984, the United States Food and Drug Administration first approved cochlear implants for adult use. Eligible patients had to be over eighteen years old, and had to have lost their hearing after acquiring spoken language skills. In 1990, the FDA lowered the approved implantation age to two years old.
The next year, the National Association of the Deaf, America’s oldest and largest advocacy group for the deaf and hard of hearing, published a position statement on pediatric cochlear implantation. It described the procedure as an “invasive surgery upon defenseless children” and the devices as “cultural genocide.”
From below, the 37-meter radio telescope at the Haystack Observatory looks like a giant mushroom. The antenna’s two hundred tons tower above my head in the warm gloom of the radome, the Epcot-like bubble of resin and fiberglass panels that protects the dish from the elements and echoes with “dome thunder” when the wind rises. Bars of metal framework cookie-cutter the dome’s tan surface into triangles. Some of the bottom panels are water-damaged, splotched with ochre swipes that resemble failed stained glass. Only the damaged panels show glimpses outside, but the whole thing—minus the metal—is actually transparent to radio waves, explains my guide, Haystack astronomer Sheperd Doeleman. If we had radio goggles on, he says, we wouldn’t even see the dome.
This antenna, arcing above the tree line about a forty-five minute drive northwest of Boston, won’t be here much longer. The U.S. Air Force uses the scope to track satellites, and their desire for a smoother, more precise dish will soon bring one of the largest cranes in the country to lift off the radome, remove the antenna, and put another mushroom top in its place. The new dish will have a surface so level that its highest point will be 0.1 millimeters high, three times better than the present antenna; if Asia were equally flat, Mount Everest would rise a mere 67 feet into the air. Such smoothness will allow researchers to better see past Earth’s atmosphere when tuning in to radio frequencies from space.
The dish may become part of the Event Horizon Telescope project, a network of radio telescopes Doeleman and an international collaboration of astronomers are assembling. EHT antennae observe in unison across the world; when fully united, they will act like a single dish so large it would stretch from the South Pole to southern Europe. The project’s astronomers will combine their observations much as detectives combine witnesses’ views of a crime scene in order to probe the enigmatic dark objects known as black holes.
Black holes are cosmic mysteries seen only by their effects. Astronomers know they are massive, compact objects—the biggest ones stuff the mass of billions of Suns into a space smaller than the Solar System, like shoving the entire Earth into the top of your pinky finger. They lurk among the stars and at the center of nearly every large galaxy in the universe, including our own. Scientists assume that these unseen monsters are the black holes predicted by Einstein’s equations of general relativity. But in fact, the evidence for that assumption is as unseen as the black holes themselves. No one really knows what lies at the centers of galaxies.
Doeleman intends to change that. A calm, collected, yet intensely enthusiastic man, he exudes authority even when his disheveled dark hair curls up near one temple like a single horn. He wields a presence in a room, an intelligence that shines through his friendly, down-to-earth nature. Doeleman’s collaborators call the project “Shep’s Event Horizon Telescope,” like a dream made solid in the vision of one man. The technique the EHT will use to peer into the hearts of galaxies isn’t Doeleman’s invention, nor is he the only observer to use it to study supermassive black holes. But of roughly thirty participants who gathered at Haystack for a workshop this past January, Doeleman stood as flag bearer and captain. Astronomers from across the world have allied with him in his quest, representing observatories nestled in the French Alps, perched atop a dormant Hawaiian volcano, bunkered down in the bitter cold of Antarctica. With him, these astronomers plan an attack on one of the greatest mysteries of the cosmos.
The focus of their assault lies at the event horizon. The event horizon is the point of no return around a black hole, the closest distance light can approach before the black hole’s gravity captures it forever. Einstein’s equations make specific predictions about what this environment should look like: if a disk of gas and dust surrounds the black hole, the event horizon will be a dark silhouette framed by streaks of light, superimposed on a softer glow. It is an environment no one has ever seen. Within the next decade, if everything goes smoothly, that will no longer be the case.
The EHT’s first target is the supermassive black hole allegedly sulking at the center of our own Milky Way Galaxy, an object known in astronomers’ argot as Sagittarius A* (pronounced “A-star”). While the case for Sgr A* being a black hole is strong, it remains a galactic Al Capone, eluding conviction, thumbing its nose at astronomers, dancing just out of reach of the handcuffs of scientific certainty. But Doeleman’s team has already detected some kind of structure in the gas and dust near (what may be) Sgr A*’s event horizon; even now they are piercing closer within the object’s influence. Doeleman hopes to actually image the event horizon’s silhouette in five or six years, nailing its identity once and for all.
That’s an incredible shift from a few decades ago, when black holes were a theoretical quirk. Highly probable on paper, they were doubted more than touted; many scientists didn’t believe they even existed. Nowadays, though, black holes appear to be everywhere, from behemoths in the cores of almost every galaxy to more modest, stellar-mass objects spattering the Milky Way’s arms. Astronomers suspect that supermassive black holes like Sgr A* may be a cosmic mafia manipulating the galaxies that house them, possibly even controlling the growth of these immense systems of stars, systems across which light can take hundreds of thousands of years to travel. If this suspicion turns out to be true, black holes may have had more influence on the structure of the cosmos than any other object. As Doeleman puts it, “Understanding the whole history of the universe is locked up in understanding black holes….”
A few blocks from Harvard Medical School stands an unremarkable office building sandwiched between an ice cream shop and a grocery store. Down the street is the cluster of world-renowned hospitals that make up Boston’s Longwood Medical Area. However, there at 1 Brigham Circle, there are no operating rooms and no laboratories. no MRI machines or CT scanners. Yet here, in a modest office on the third floor, Dr. Adam Wright sits at his computer slowly reshaping the world of medicine.
Wright is a biomedical informaticist, a man who deals in the science of medical data; he spends each day working on the electronic medical record system used by several hospitals in Boston. A computer scientist by training, Wright works for the department of general medicine at Brigham & Women’s Hospital.
On screen is an electronic medical record. The patient is a 75-year-old man with diabetes and a host of other ailments. The patient has missed a number of lab tests and screenings as well as his recommended pneumonia and flu vaccines. In all, the record paints a picture of a person at risk and in poor health.
Normally, this situation would raise red flags. The man’s diabetes is unmanaged and his health is in danger. Fortunately, however, this chart does not represent a real person. This test patient, full name Mr. BHWLMR MapleTest10 is a figment of the computer’s imagination, created by Wright to test the system. Among Wright’s other fictitious patients are Frodo, Santa Claus and many less whimsically named.
Today, Wright is not interested in treating this patient. In fact, in order to demonstrate one of the safety features of his system, Wright is going to try to kill him.
>In 1941, V. E. Yarsley and E. G. Couzens, two British applied chemists, in a thin primer entitled “Plastics,” declared the material’s significance, writing: “Now it can confidently be stated that there is no other material possessing all these qualities as does the average plastic.” It was better than wood, which was prone to rot and unpredictable with its uneven grain; porcelain, which was heavy and broke easily; metal, which rusted, weighed a ton, and was difficult to manipulate; and marble, which, again, was heavy, as well as rare and, therefore, expensive.
When Yarsley and Couzens wrote, plastics were still in their infancy….Yet the authors, in their enthusiasm, ventured a prophesy in which they imagined the life of a future “dweller in the ‘Plastic Age’ that is already upon us,” writing:
“This ‘Plastic Man’ will come into a world of colour and bright shining surfaces, where childish hands find nothing to break, no sharp edges or corners to cut or graze, no crevices to harbour dirt or germs…he is surrounded on every side by this tough, safe, clean material which human thought has created…As he grows up he cleans his teeth and brushes his hair with plastic brushes with plastic bristles, clothes himself in plastic clothes of synthetic silk and wool…writes his lessons with a plastic pen and does his lessons with books bound in plastic…The windows of [his] school…are unbreakable, and transmit the life-giving ultra-violet rays, and the frames…are of moulded plastic, light and easy to open, and never requiring any paint to prevent them from warping or rusting…but lest this picture seem too coldly hygienic, remember that everywhere there is a riot of colour and every kind of surface from dull matt to a mirror-finish that circumstances demand.”
The prophesy follows the ‘Plastic Man’ throughout the course of his life, during which he lives and works in a “universal plastic environment,” and turns to plastic for beauty and leisure. At the end of his life, we find the ‘Plastic Man’ “getting tired and old.” The authors continue:
“His own teeth are gone and he wears a plastic denture with ‘silent’ plastic teeth and spectacles of plastic with plastic lenses…until at last he sinks into his grave hygienically enclosed in a plastic coffin.”
If the modern reader perceives Yarsley and Couzens’ dream, featuring plastic’s near complete integration into our lives, as ironic, it’s only because it so closely mirrors present reality. To this day, plastic continues to make good on its promise as a “miracle material.” Even its harshest critics won’t begrudge a soldier his body armor or a doctor her sterilized equipment. There is, arguably, not a single industry—transportation, technology, clothing, food, medical, aerospace—that plastics hasn’t transformed in its short existence.
Yet, in the same short time, plastic trash has come to live as more of a scourge in the public perception than any other material waste. Unlike discarded paper, wood or metal scrap, plastic trash evokes responses of revulsion that have begun to carry over, condemning plastics in general. Where then did the “miracle material” go wrong?
Organic farming is easy on the mind: natural people cultivating natural food using natural soil enhancements. Because they don’t use petroleum-based pesticides and synthetic fertilizers, organic farmers feel they practice truly sustainable agriculture.
But one problem is that it’s hard. It’s slow. It’s expensive. Jim Buckel, a farmer who uses organic methods a the Boston area’s last working farm – Allandale Farm – tells me his kind of farming is pretty grueling. Jim’s farm’s cash crop is tomatoes; during tomato season, he and his team of workers begin harvesting at 5:30 in the morning, and stay until seven in the evening to pack their tomato orders. He and his team put in seventy to eighty hours of work per week for 25 weeks. he says, “Now that I’m getting a little older, I can’t go and harvest like these younger guys. These guys can really fly through stuff.” He’s thirty-three.
One reason for his hard work is the piecemeal nature of organic farms. If a requirement of true organic farming is a diversity of crops, then you have to harvest each crop individually. One combine – a reaping, threshing harvest tractor – will not pick your strawberries, pluck your raspberries, pull your carrots, dig your potatoes, or clip your dill. Each of these fruits, vegetables, and spices must be picked by hand. And, based on organic’s idea of crop rotation, Buckle plants each of his fields three, four or five times – so each field requires more than one harvest. It is intense physical labor – a kind of labor that seems to wear a guy out by his third decade.
That combine is a one-time investment, too, though one can imagine its upkeep is not cheap. But the tractor will do the work of a whole crew of farmhands, a crew of farmhands that require an hourly wage. Planting, weeding, irrigating, and harvesting fields of vegetables several times over in a single growing season requires a lot of paid man hours.
And after all this – the weeding of acres of vegetables by hand, the stooped labor of harvest, the intricacies of crop rotation and soil maintenance – many wonder whether organic farming can produce enough food to become more than simply a niche market. Can the kind of farming which saps so much energy from the very people who uphold it produce enough food to feed the world? Can we manage the soil so that each slice of the world is fed, comfortable, full-bellied? as the world population surges toward nine billion people – expected to hit that mark by 2050 – many, like University of Nebraska’s agoecologist Ken Cassman, wonder how the world will grow enough food to feed itself by any means of agriculture, let alone organic. Others wonder about areas of the world where irrigation and pest control is a serious problem, where infrastructure is so fractured or nonexistant that distributing food is an issue. Sociologists worry about organic’s high price. And some of our nation’s poorest simply want to eat.
There is a concert on in the siamang pen at the Dormand Zoo in Germany. Two siamangs, a male and a female, sit facing each other high atop the wooden scaffolding erected in the center of their pen. Arms covered in thick black fur grip the wooden beams overhead, and each adult sways slightly, watching the skittering of a siamang youngster that swings on the beams from one adult to the other, then back again. Khaki colored pouches rise out of the black fur on their neck, swelling and bulging as they hoot in response to one another. As the concert progresses, the siamangs begin to groove to the rhythm of their song. They leap up, swing around the beam and wave their arms.
Siamangs are the loudest and largest of the gibbons – a family of black-furred apes that are native to East and South Asia. Gibbons are tree swingers, leaping and swinging up to 8 meters, at speeds that can reach 35 miles per hour. Of the 9 sub-species of gibbon, 7 are known to sing. Of these, the siamang makes the loudest, most complex call.
Thomas Geissmann, a researcher at Anthropological Institute, University Zürich-Irchel in Switzerland, calls this siamang duet, characteristic of a mated pair of siamangs, the closest the animal kingdom gets to what we understand as a “love song.” Investigating this group of primates, Geissmann believes, yields clues to the origins of human music.
“The coordination of song is something that occurs very rarely among mammals… And duetting, even more so,” says Geissmann, “this something you find among apes only in gibbons and in humans.” Pairing for life, siamang couples develop well-honed routines that establish their relationship with one another. A well-developed duet warns other siamangs that the two are a pair. In the early stages of courtship, broken, clumsy duetting is a signal to the rest of the family that the duetting siamangs are emerging as a couple. Geissmann’s data reveals that robust, well-rehearsed routines between duetting siamangs are an indication of a long and healthy relationship.
The species and sex-specificity of gibbon song as described in Geissmann’s first works suggests that singing in these primates usually develops between gibbon pairs. Geissmann believes that the song also serves a larger function – to reinforce the sense of community that comes with living in a family. Geissmann says that singing occurs through the entire family unit. When there are offspring, little siamangs chirp in like a choir. “In a family group, you have not only have adult pairs, you also have offspring,” Geissmann says, “and very often offspring chime into the duet, so as to produce a concert.”
As he continued to study gibbon “song,” Geissmann began to note a resemblance to human music. For one, the notes that the gibbons sing are produced at a very specific pitch. Also, there is a clear structure to their melodic phrases. “Singing means producing different types of notes in a predetermined, syntactical phrase,” says Geissmann, “[In gibbons] you have phrases that can be recognized, and the phrases and ordered in a particular sequence. The notes are tonal – not sounds – tones.”
Gibbons are never still when they perform. …“There’s a certain part of their song where they have to burst into locomotion,” Geissmann says, “They must do it.” He says that the need to foot-tap or beat rhythm is a tendency that, like in the gibbons, evolved in human beings as well. “The fact that there is music that is so hypnotic for the listener that it is difficult to sit still suggests that there is an inborn element in humans that reacts to music,” Geissmann says, “And this inborn quality is the same thing that happens in primates when they produce a loud call, or gibbons when they sing.”
…Biologists call features which share a common ancestor “homologs.” For example, the wings of the bat and the wings of the bird are homologs, both sharing an origin in the vertebrate forearm. Over time, a homolog could change, retaining some features of the original trait, and losing others. According to Geissmann, human music and gibbon song are homologs that originated in an ancestral singing primate.
But our early primate ancestor was no Frank Sinatra. His singing was an announcement of the location of food, or the location of certain members of the social group. And most importantly, Geissmann says, it kept the group together. “The most widely distributed … and probably the most likely function of early hominid music,” Geissmann says in Origins, “is to display and possibly reinforce the unity of a social group toward other groups.” Geissmann sees lingering evidence of this function in human music today. “National hymns, military music, battle songs of fans and cheerleaders encouraging their favorite sports teams, or the strict musical preferences of youth gangs we may be continuing what an early primate ancestor started a long time ago,” he says.
As far as homologs go, music is an oddity. Most homologs leave a fossil trail behind them, and archaeologists are able to piece together their evolutionary history. But music does not fossilize. “I suspect it is a homolog but I can’t prove it,” Geissmann says, “… these lineages have diverged from each other such a long time ago, that the few similarities in the calls you find could be just coincidences. Or, they could be the evidence for a common ancestor. It’s difficult to be sure.”