First Light: The Search for the Edge of the Universe

by Richard Preston

  There was no way out of this universe. Schmidt, Oke, Greenstein, and Matthews (the radio astronomer) scrambled to write a string of papers for Nature, which all appeared in a row. Schmidt’s paper came first—“3C 273: A Star-Like Object with Large Redshift.” It was two pages long. There was nothing much to say, really. Nature had turned out not to be complicated and explainable, but uncompromising, simple, and mysterious. Nature offered alibis to no one. These two pages marked a turning point in the history of astronomy, announcing a new heaven spattered with explosive, eerie phenomena—two pages that were a prologue to two decades of astronomy that would reveal pulsars, accretion disks, black holes, gamma-ray bursters, radio jets, gravitational lenses, and the baroque, inevitable logic of the Big Bang, the moment of creation. When more and more quasars were discovered, and when their deepening redshifts pointed his way into lookback time, Maarten Schmidt came to see that when he had dusted that slide with his handkerchief and stuck it in the microscope, he had accidentally stumbled into a quest known as observational cosmology, whereby one tries to figure out the structure and history of the universe by examining it in a looking glass.

  As for Jesse Greenstein, he would soon blow a good deal of money amassing a collection of Japanese Zen paintings. Jesse considered his paintings not exactly a consolation for having let the redshift of the quasars slip through his grasp, but rather a lesson. “I had known that 3C 48 had a redshift,” he said. “And I had thrown that notion out. ‘This is nonsense,’ I said.” He collected paintings that illustrated Zen koans, riddles. One of his favorites shows an old poet riding in a boat, watching geese fly across a cloudy, moon-illuminated sky. The poet is looking up, and one can hardly see his eyes. The riddle is: How does the old poet catch the geese? And the answer is: He has already caught them.

  Jim Gunn and Don Schneider were working in the data room, trying to prepare 4-shooter to scan. They hammered at keys, while Maarten Schmidt chatted with Juan. Suddenly Jim and Don shouted, “Oh, no!” and ran out of the room.

  “Anything wrong?” Maarten called after them.

  No reply.

  A printer in the data room started spitting paper. It said:

  OK

  OK

  OK

  Maarten contemplated it with a smile.

  OK

  OK

  OK

  “It’s saying okay all the time,” Maarten said, “but I don’t think it’s okay.”

  OK

  OK

  OK

  Jim and Don raced back into the data room. They pounded keys, trying to soothe 4-shooter.

  “I don’t understand a blessed thing of what is going on at the moment,” Maarten said. “Actually it feels quite normal.”

  “Now it’s okay,” Jim said, while Don gathered up a mound of coiled computer paper. Maarten hovered over them. He said, “You are boldly going where no man knows what he is doing.”

  They persuaded 4-shooter to start scanning, and stars and galaxies drifted up the screens, but the galaxies looked very different this time. Each galaxy threw out a vertical smear, resembling a candle flame. The screen displayed images of galaxies as seen through flat pieces of glass known as diffraction gratings. Such glasses decompose light, as does a prism. Jim had placed the glasses in front of the four cameras inside 4-shooter, so that the light of every object in the field of view passed through the glass on its way into the camera. This technique smashes apart the light of everything in the telescope’s field of view. The galaxies appeared to be on fire. Each flame was a spectrum emerging vertically from the galaxy. During two nights of scanning, 4-shooter would pass over the same strand of sky twice, taking direct images on the first night, taking images through diffraction gratings on the second night, thereby acquiring pictures of about 120,000 objects along with their broken colors, all of which information would be recorded on tape. Don’s computer would later combine the images to intensify the light, and then automatically search the spectra for emission lines typical of quasars. In that way the team hoped to find quasars.

  “We are working!” cried Maarten. He strode to the stereo, and within moments he had found Mozart.

  The astronomers gathered around a screen to read the spectra.

  “Maarten, look at this,” said Jim, his finger tracing bumps and gaps in a candle flame. “That’s an early M star.” (He later explained to me that an M star is a cool, reddish, aging star.)

  Maarten took off his glasses and squinted at it. “Ja,” he said. “A rather blue M-type.”

  The sky on the television screen was a mass of blots and smears. Some spectra had dark cuts in them—absorption lines. Others showed swellings—emission lines. The astronomers noticed many M stars. M stars, they said, superficially resembled quasars. “Most of them are pretty close to us,” Schneider said. “Within a few thousand light-years away.” Later he touched the screen. “There’s an emission galaxy,” he said, indicating a bright, violent galaxy with something nasty burning in its core, perhaps a mini-quasar.

  “Ah, yes,” Maarten said, tracing the spectrum with his finger. “Look at that. An N galaxy.” He pointed to a bundle of horizontal spikes in the candle flame. “You can see emission lines, but it is clearly a galaxy and not a quasar,” he said.

  These multiple transits on the Big Eye suggested the rhythm of long-distance driving across North America at night. Galaxies sparkled on the video screens like the lights of lonely towns. The talk rose and fell, and often the astronomers stared in silence.

  “A carbon line?” Don said, touching another spectrum moving on the screen. “This could be a quasar.”

  “For this we need the supercomputer,” Maarten said. He twirled his circular slide rule. “The emission lines on that object are a bit too far apart to be carbon. So I’d say that’s a magnesium break. It’s only an emission galaxy. Sorry, gentlemen.”

  Later Maarten said to Jim, “I think it’s about time we saw a quasar go by, James, don’t you?”

  “Absolutely.”

  “We need to see a quasar,” Don said.

  One night the door of the data room swung open, and an astronomer who had been working on the forty-eight-inch Schmidt telescope walked in. “I am really ticked off,” he said. “It’s the second bomber tonight.”

  “The second what?” Don asked.

  “B-52! Some idiot up there crossed right through my field with a blinking strobe light and all kinds of insanity. He just ruined my plate. I think those guys are vectoring off our domes on night bombing runs.” He leaned over and looked at the screen. “Hey. This is impressive. Have you seen any quasars?”

  “We would surely like to,” Gunn said.

  “Gunn, this is really impressive. You could sell tickets to this.”

  Gunn called to Schmidt, who was on the other side of the room, “Maarten, did you hear that? Who cares about a few spectra when you can get a hundred thousand?”

  “Ja, that’s pretty good!”

  On another occasion Schmidt, who had been walking restlessly around the room, suddenly whirled on his feet. He had seen something moving on the screen, out of the corner of his eye. “By God,” he said. He ripped off his glasses. He grabbed a ruler and put it against a spectrum floating up the screen. He pulled out his circular slide rule and twirled it. “Redshift, let me see! Yes! That was a quasar!”

  The astronomers’ chairs, which were on wheels, thundered up to the video screen. “That was a bright one,” Gunn said as the quasar disappeared at the top of the screen.

  During the past year, Don Schneider had been writing a massive engine of software to find quasars, which, everyone hoped, would find this quasar again. To my eyes the quasar had been indistinguishable from the hordes of spectra splattered across the monitor. Maarten’s reaction reminded me of a fly fisherman, working a slick in a Maine river, who hears an odd, faint skitter of droplets, turns, and, without missing a beat in his cast, drops the fly three feet up-current from the boil of a resting salmon.

  A blast
of white flooded the screen. “A little tiny star,” Jim mused. “You couldn’t see it with the naked eye.”

  Don remarked, “I just hope we don’t cross Orion’s Belt.”

  “Say! Which way were we supposed to be going?” Maarten joked.

  “Or the moon,” said Juan Carrasco. “Then it would be good-bye screen.”

  A cluster of galaxies drifted up the screen, spectra bleeding out of them.

  “It looks like those galaxies multiplied,” said Juan.

  “It’s the other way around,” Don said. “They eat each other up.”

  “Is that right?” said Juan.

  Maarten pointed to the screen. “That little galaxy, Juan, is that big one’s lunch for the next billion years.”

  “Something terrible happened at the office today.” After Christmas, 1963, at a conference held in Dallas, astronomers argued about the proper name for these quasi-stellar objects. Someone proposed the name Dallas Stars. Someone else thought they should be called Kennedies, in memory of President John F. Kennedy, who had been shot in Dallas the month before. (The term quasar finally became official in 1970.) Maarten Schmidt began receiving record amounts of dark time on the Hale Telescope. Sitting alone in prime focus and zeroing the crosshairs to the music of Bach, Maarten Schmidt broke open the universe.

  On April Fool’s Day, 1965, the Astrophysical Journal stopped the presses to wait for a letter to the editor from Maarten Schmidt. The letter was no joke. After two years of work he had found five quasars. By a series of tight deductions, he had linked the emission lines of the five quasars into a ladder of logic that had taken him into breathtaking distances. One quasar, he found, was redshifted by 70 percent. Expressed as a ratio, that quasar’s redshift was 0.7. (Astronomers usually express redshift as a ratio rather than as a percentage.) Another quasar had a redshift of 1.03—redshifted by 103 percent. The monster was a quasar called 3C 9, with a redshift of 2.01—an awesome 201 percent—and yet this quasar was bright blue in color, because a normally invisible ultraviolet glow in the spectrum, called the Lyman alpha line, had been redshifted down into visible wavelengths, where it tinted the quasar with the color of a pale sapphire.

  Astronomers do not know the exact distance from our neck of the woods to a deeply redshifted quasar, because astronomers have not yet been able to link redshift to a distance scale. For example, the quasar 3C 9, with a redshift of 2.01, is probably somewhere between ten and sixteen billion light-years distant from the Milky Way; the photons coming from that quasar are anywhere from two to three and a half times as old as the earth. Maarten once said that he was quite proud of his April Fool’s quasars. By showing that one could find a quasar with a redshift of 2.01, he had tripled the range of the Hale Telescope in all directions from the earth. He had opened up a shell of explorable space that, in terms of volume, was fifty times bigger than the volume of space that had been available to the Hale Telescope before. In a letter to an editor he had enlarged the known volume of the universe fifty times over. “That,” he said, “was the most difficult job I have ever done.”

  The news of quasars reached the pages of Reader’s Digest in the year 1966, and a copy of that magazine traveled to an old lady who lived on a farm near Heartwell, Nebraska, which was then a hamlet without a paved street, situated on the high, treeless plains south of the Platte River. Her name was Mrs. Gertrude Schneider. On Sunday afternoons her eleven-year-old grandson, Donnie, used to drop by to visit with her and, incidentally, to read her Reader’s Digest. It was at his grandmother’s farm, reading Reader’s Digest, that Don Schneider first learned about Maarten Schmidt. He began to feel the presence of quasars over his head. “That was when I gave up dinosaurs for astronomy,” Don says. “It was the last career switch I ever made. By the time I was in sixth grade, I knew that I was going to be an astronomer, at least as much as a child can ever know what he will become.” Don always felt that he had chosen a normal career. “How anyone can go out at night and look up and not want to be an astronomer is beyond me.”

  When he told his parents that he was going to be an astronomer, they were pleased, because they originally had not had high hopes for Donnie. He had been a slow baby. At the age of three and a half Donnie still had not learned how to talk. They had begun to fear that he was mentally retarded, and they had made plans to send him to a doctor. Then one day Donnie was sitting in his grandmother’s lap while she read a book to him, hoping to encourage him to speak. She pointed to a picture of a barrel and said, “Keg. Can you say that? Keg.”

  “Barrel,” Donnie said.

  “What?”

  “Barrel,” he said, pointing to the word.

  “Are you reading this?”

  “Yes.”

  She flipped the pages, pointing to other words, and he read the words aloud. He had not had anything to say until he could read it first, at three and a half.

  Donnie puzzled his mother too. Eileen Schneider taught catechism in Sunday school, and when Donnie was in first grade, he was one of her pupils. She tried to explain to the children what would happen at the end of the world, at the coming of the Son of Man. She read from Matthew: “ ‘The sun shall be darkened and the moon shall not give her light and the stars shall fall from heaven and the powers of heaven shall be moved.…’ ”

  Donnie’s hand shot up. “Mother,” he said, “the moon doesn’t give light. It reflects the light of the sun.”

  That did not make catechism any easier.

  His father, Donnie Ray Schneider, was a sharecropper and the mayor of Heartwell. He farmed corn, wheat, and sorghum on sections of land around Heartwell that belonged to other people. He worked as hard as any man in Heartwell, and people there say that Donnie Ray Schneider never walked anywhere, he ran. He wanted to save up enough money to buy a farm of his own, but there were times when the crops would fail two years in a row, and then he could barely feed his family, although he continued to buy books for his oldest boy, because Donnie was a reader. Donnie Ray figured that someday Donnie would work alongside him and help him build a farm, until the boy announced that he was going to be an astronomer, which was really all right, since it had already become clear that he was not going to make much of a farmer. Donnie Ray had to carry the boy out of bed most mornings and put him on the tractor and wrap his hands around the steering wheel and turn the ignition key before the boy woke up, which perhaps explains what happened when he left Donnie alone one day on the tractor, pulling a giant disc and harrow. Donnie threw the tractor into gear and began to disc the land. He enjoyed open plains, deep sky, and horizons. The sky was always a presence in Nebraska, where one’s eye could jump to the edge of the world without hitting so much as a tree. The tractor churned along, and then it came time to refuel.

  He had never refueled the tractor while pulling a large piece of machinery. It was a tricky job. He had to drive the tractor alongside a pickup truck. The pickup held a tankful of diesel fuel and a hose. He made a slow pass alongside the pickup truck—a practice flyby. He was too far away, decided to circle around again, and gunned the throttle. As Don tells the story, “I heard this tremendous crash. I looked back. All I could see was a cloud of dust and a dancing pickup truck.” He had forgotten about that disc and harrow. They had caught the pickup truck and were discing and harrowing it. “The disc,” Don says, “didn’t even know the pickup was there.” Don unhooked the tractor from the wreckage and drove the tractor like mad to another field, where his father was cutting wheat. “Dad,” he said, “I think I destroyed your pickup truck.”

  The words of the mayor of Heartwell were: “Okay, Donnie, we’ve gotta make hay while the sun shines. I’ll take a look at it later.”

  Wheat harvest arrived in July. At the same time they had to begin irrigating the corn. Don would get up with his father before sunrise, load a quarter of a mile of irrigation pipe into a trailer, and then set the pipe in another field, laying the pipe sections by hand. After that his father and his uncle would join forces to start cutting the wheat
with combines, and Don would help them. Don’s mother or his aunt would make up a supper in a picnic basket. In the hot evening the men, Don, and his cousins would sit in the shade of a truck and eat while the sun went down, and then they would work into the night with the combines, shining lights into the wheat until the dew rose and they had to stop.

  Don’s father finally saved enough to buy a farm of his own. In 1973, the Schneider family moved outside Heartwell to a yellow house surrounded by a picket of evergreen trees, to keep out the high plains wind, but entropy had a way of coming through windbreaks. Don can remember his father picking up a full thirty-gallon drum of oil and putting it into a trailer in a manner that suggested that the barrel contained popcorn. But secretly at first, and then gradually happening in a more apparent way, Donnie Ray’s heart changed into that of an old man. He died of heart failure one April in a hospital in Lincoln, just before planting time. Don was in his second year at the University of Nebraska. The other kids in the family were too young to work machinery, and his mother had never even learned how to drive a car. Don thought that he would have to plant the crops alone, until a crowd of tractors showed up in front of the Schneider farm. Most of the farmers in Heartwell put in the Schneider crops, after which Don and a hired man took over. “That summer,” Don recalls, “I just did what the hired man told me.” Don’s mother learned how to drive a car. By autumn, Eileen Schneider felt that she faced a decision: either her son became a farmer, as his father had been, or he got a college education. Without consulting Don, she auctioned off all of the family’s farm machinery in order to make sure that Don finished college. She has remarried and now lives modestly but comfortably on the farm, renting the land to other farmers.