The Best of Gregory Benford

by David G. Hartwell

  “Y’see here?” An observing schedule sheet. “The times when G369.23–0.82 is in the sky, I’ve only got three slices when we’re reconfiguring the dishes. Each maybe half an hour long.”

  “Damn!” He grimaced. “Not much.”

  “No.” Harkin looked a bit sheepish. “When I made that promise to you, well, I thought better of it the next day. But you’d already left for your flight in Geneva.”

  “Vin Local,” Ralph said. “It hit me pretty hard, too.”

  Harkin nodded at his feet, embarrassed. “Uh, okay, so about G369.23–0.82—”

  “I call it the Bullet. Easier than G369.23–0.82.”

  “Oh yeah.” Hankin shrugged. “You said that in Briancon.”

  But what could he do in half hour fragments? He was thinking this through when Harkin asked the same question.

  “Andy pretty well showed there was no pulsar beam,” Harkin said helpfully, “so…?”

  Ralph thumbed through his notes. “Can I get good clarity at the front end? The Bullet’s bow shock?”

  Harkin shook his head, looking disappointed. “No way, with so little observing time. Look, you said you had some out of the box ideas.”

  Ralph thought furiously. “How about the Bullet’s tail, then?”

  Harkin looked doubtful, scribbled a few numbers on a yellow lined pad. “Nope. It’s not that luminous. The wake dies off pretty fast behind. Confusion limited. You’d get nothing but noise.”

  Ralph pointed. “There’s a star we can see at the edge of the Bullet.”

  Harkin nodded. “A foreground star. Might be useful in narrowing down how far away it is.”

  “The usual methods say it’s a long way off, maybe halfway across the galaxy.”

  “Um. Okay, leave that for later.”

  Ralph searched his mind. “Andy looked for pulses in what range?” He flipped through his notes from Briancon. “Short ones, yes—and nothing slower than a ten second period.”

  Harkin nodded. “This is a young neutron star. It’ll be spinning fast.”

  Ralph hated looking like an amateur in Harkin’s eyes, but he held his gaze firmly. “Maybe. Unless plowing through all that gas slows it faster.”

  Harkin raised his eyebrows skeptically. “The Mouse didn’t slow down. It’s spinning at about a tenth of a second period. Yusef-Zadeh and those guys say it’s maybe 25,000 years old.”

  Twenty-five thousand years was quite young for a pulsar. The Mouse pulsar was a sphere of nothing but neutrons, a solar mass packed into a ball as small as San Francisco, spinning around ten times a second. In the radio-telescope maps that lighthouse beam came, from a dot at the very tip of a snout, with a bulging body right behind, and a long, thin tail: mousy. The Mouse discovery had set the paradigm. But just being first didn’t mean it was typical.

  Ralph set his jaw, flying on instinct—“Let’s see.”

  So in the half hours when the dish team, instructed by Harkin, was slewing the big white antennas around, chugging them along the railroad tracks to new positions, and getting them set for another hours-long observation—in those wedges, Ralph worked furiously. With Harkin overseeing the complex hand-offs, he could command two or three dishes. For best use of this squeezed schedule, he figured to operate in the medium microwave band, around 1 or 2Ghz. They had been getting some interference the last few days, Harkin said, maybe from cell phone traffic, even out here in the middle of a high desert plateau—but that interference was down around 1 Ghz, safely far below in frequency. He need not worry about callers ringing each other up every few minutes and screwing up his data.

  He took data carefully, in a way biased for looking at very long time fluctuations. In pulsar theory, a neutron star was in advanced old age by the time the period of its rotation, and so the sweeping of its lighthouse beam, was a second long. They harnessed their rotation to spew out their blaring radiation—live fast, die young. Teenage agonies. Only they didn’t leave beautiful corpses—they were corpses. Pulsars should fade away for even slower rates; only a handfull were known out in the two or three minute zone.

  So this search was pretty hopeless. But it was all he could think of, given the half hour limit.

  He was dragging by the time he got his third half hour. The dish team was crisp, efficient, but the long observing runs between his slices got tedious. So he used their ample computing resources to process his own data—big files of numbers that the VLA software devoured as he watched the screens. Harkin’s software had fractured the Bullet signal into bins, looking for structure in time. It caressed every incoming microwave, looking for repeating patterns. The computers ran for hours.

  Hash, most of it. But then…

  “What’s that?” He pointed to a blip that stuck up in the noisy field. The screen before him and Harkin was patchy, a blizzard of harmonics that met and clashed and faded. But as the Bullet data ran and filtered, a peak persisted.

  Harkin frowned. “Some pattern repeating in the microwaves.” He worked the data, peering at shifting patterns on the screen. “Period of…lessee…47 seconds. Pretty long for a young pulsar.”

  “That’s got to be wrong. Much too long.”

  In astronomy it paid to be a skeptic about your work. Everybody would be ready to pounce on an error. Joe Weber made some false detections of gravitational waves, using methods he invented. His reputation never fully recovered, despite being a brilliant, original scientist.

  Harkin’s face stiffened. “I don’t care. That’s what it is.”

  “Got to be wrong.”

  “Damn it, Ralph, I know my own codes.”

  “Let’s look hard at this.”

  Another few hours showed that it wasn’t wrong.

  “Okay—funny, but it’s real.” Ralph thought, rubbing his eyes. “So let’s look at the pulse itself.”

  Only there wasn’t one. The pattern didn’t spread over a broad frequency band. Instead, it was there in the 11 gigaHertz range, sharp and clear—and no other peaks at all.

  “That’s not a pulsar,” Harkin said.

  Ralph felt his pulse quicken. “A repeating brightness. From something peaking out of the noise and coming around to our point of view every 47 seconds.”

  “Damn funny.” Harkin looked worried. “Hope it’s not a defect in the codes.”

  Ralph hadn’t thought of that. “But these are the best filter codes in the world.”

  Harkin grinned, brown face rumpling like leather. “More compliments like that and you’ll turn my pretty little head.”

  So Harkin spent two hours in deep scrutiny of the VLA data processing software—and came up empty. Ralph didn’t mind because it gave him time to think. He took a break partway through—Harkin was not the sort to take breaks at all—and watched a Cubs game with some of the engineers in the Operations room. They had a dish down for repairs but it was good enough to tip toward the horizon and pick up the local broadcast from Chicago. The Cubs weren’t on any national ’cast and two of the guys came from UC, where the C was for Chicago. The Cubs lost but they did it well, so when he went back Ralph felt relaxed. He had also had an idea. Or maybe half of one.

  “What if it’s lots bigger than a neutron star?” he asked Harkin, who hadn’t moved from his swivel chair in front of the six-screen display.

  “Then what’s the energy source?”

  “I dunno. Point is, maybe it’s something more ordinary, but still moving fast.”

  “Like what?”

  “Say, a white dwarf—but a really old, dead one.”

  “So we can’t see it in the visible?” The Hubble telescope had already checked at the Bullet location and seen nothing.

  “Ejected from some stellar system, moving fast, but not a neutron star—maybe?”

  Harkin looked skeptical. “Um. Have to think about it. But…what makes the relativistic electrons, to give us the microwaves?”

  That one was harder to figure. Elderly white dwarfs couldn’t make the electrons, certainly. Ralph paused and said,
“Look, I don’t know. And I have to get back to UCI for classes. Can I get some more time wedged in between your reconfigs?”

  Harkin looked skeptical. “I’ll have to see.”

  “Can you just send the results to me, when you can find some time?”

  “You can process it yourself?”

  “Give me the software and, yeah, sure.”

  Harkin shrugged. “That 47 second thing is damn funny. So…okay, I suppose…”

  “Great!” Ralph was tired but he at least had his hand in the game. Wherever it led.

  Ralph spent hours the next day learning the filter codes, tip-toeing through the labyrinth of Harkin’s methods. Many thought Harkin was the best big-dish observer in the world, playing the electronics like a violin.

  Harkin was a good teacher because he did not know how to teach. Instead he just showed. With it came stories and examples, some of them even jokes, and some puzzling until Harkin changed a viewing parameter or slid a new note into the song and it all came clear. This way Harkin showed him how to run the programs, to see their results skeptically. From the angular man he had learned to play a radio telescope as wide as a football field like a musical instrument, to know its quirks and deceptions, and to draw from it a truth it did not know. This was science, scrupulous and firm, but doing it was an art. In the end you had to justify every move, every conclusion, but the whole argument slid forward on intuition, like an ice cube skating on its own melt.

  “Say, Andy,” Ralph said casually into his cell phone, looking out the big windows at New Mexico scrub and the white radio dishes cupped toward the sky. “I’m trying to remember if you guys looked at long periods in your Bullet data. Remember? We talked about it at Briancon.”

  “Bullet? Oh, G369.23–0.82.”

  “Right, look, how far out did you go on period?”

  A long pause. Ralph thought he could hear street noise. “Hey, catch you at a bad time?”

  “No, just walking down Mass Ave., trying to remember. I think we went out to around 30 second periods. Didn’t see a damn thing.”

  “Oh, great. I’ve been looking at the Bullet again and my preliminary data shows something that, well, I thought I’d check with you.”

  “Wow.” Another pause. “Uh, how slow?”

  Ralph said cautiously, “Very. Uh, we’re still analyzing the data.”

  “A really old pulsar, then. I didn’t think they could still radiate when they were old.”

  “I didn’t, either. They’re not supposed to.” Ralph reminded himself to check with the theorists.

  “Then no wonder we couldn’t find its supernova remnant. That’s faded, or far away.”

  “Funny, isn’t it, that we can pick up such weak signals from a pulsar that’s halfway across the galaxy. Though it has been getting brighter, I noticed.”

  Andy sounded puzzled. “Yeah, funny. Brighter, um. I wonder if it shows up in any earlier survey.”

  “Yeah, well I thought I’d let you know.”

  Andy said slowly, “You know, I may have glimpsed something, but will get back to you.”

  They exchanged a few personal phrases and Ralph signed off.

  Harkin was working the screens but turned with eyebrows raised.

  Ralph said, “Bingo.”

  As soon as Irene came into the coffee shop and they kissed in greeting, he could see the curiosity in her eyes. She was stunning in her clingy blue dress, while he strutted in his natty suit. He had told her to dress up and she blinked rapidly, expectant. “Where are we going tonight?”

  He said, not even sitting down, “Y’know, the only place where I can sing and people don’t throw rotten fruit at me is church.”

  Irene looked startled. “I didn’t think you were religious.”

  “Hey, it’s a metaphor. I pay for a place to dance, too, so—let’s go. To the Ritz.”

  Her eyebrows arched in surprise. “What an oblique invitation. Puttin’ on the Ritz?”

  As they danced on the patio overlooking sunset surfers, he pulled a loose strand of hair aside for her, tucking it behind her ear. She was full of chatter about work. He told her about his work on the Bullet and she was genuinely interested, asking questions. Then she went back to tales of her office intrigues. Sometimes she seemed like a woman who could survive on gossip alone. He let it run down a bit and then said, as the band struck up Begin the Beguine, “I need more time.”

  She stiffened. “To contemplate the abyss of the M word?”

  “Yes. I’m hot on the trail of something.”

  “You didn’t call Herb Linzfield, either, did you.” Not a question.

  “No.”

  “Oh, fine.”

  He pulled back and gazed at her lips. Lush, as always, but twisted askew and scrunched. He knew the tone. Fine. Yeah, okay, right. Fine. Go. Leave. See. If. I. Care.

  He settled into it then, the rhythm: of thickets of detail, and of beauty coming at you, unannounced. You had to get inside the drumroll of data, hearing the software symphonies, shaped so that human eyes could make some hominid sense of it. These color-coded encrustations showed what was unseeable by the mere human eye—the colors of the microwaves. Dry numbers cloaked this beauty, hid the ferocious glory.

  When you thought about it, he thought, the wavelengths they were “seeing” with, through the enormous dish eyes, were the size of their fingers. The waves came oscillating across the blunt light years, messages out of ancient time. They slapped down on the hard metal of a radio dish and excited electrons that had been waiting there to be invited into the dance. The billions of electrons trembled and sang and their answering oscillations called forth capturing echoes in the circuits erected by men and women. More electrons joined the rising currents, fashioned by the 0s and 1s of computers into something no one had ever seen: pictures for eyes the size of mountains. These visions had never existed in the universe. They were implied by the waves, but it took intelligence to pull them out of the vagrant sizzle of radio waves, the passing microwave blizzard all life lived in but had never seen. Stories, really, or so their chimpanzee minds made of it all. Snapshots. But filling in the plot was up to them.

  In the long hours he realized that, when you narrow your search techniques tuned to pick up exactly what you’re looking for, there’s a danger. The phrase astronomers use for that is, “I wouldn’t have seen it if I hadn’t believed it.”

  The paper on the astro-ph web site was brief, quick, three pages.

  Ralph stared at it, open-mouthed, for minutes. He read it over twice. Then he called Harkin. “Andy’s group is claiming a 47 second peak in their data.”

  “Damn.”

  “He said before that they didn’t look out that far in period.”

  “So he went back and looked again.”

  “This is stealing.” Ralph was still reeling, wondering where to go with this.

  “You can pull a lot out of the noise when you know what to look for.”

  Whoosh— He exhaled, still stunned. “Yeah, I guess.”

  “He scooped us,” Harkin said flatly.

  “He’s up for tenure.”

  Harkin laughed dryly. “That’s Harvard for you.” A long pause, then he rasped, “But what is the goddamn thing?”

  The knock on his apartment door took him by surprise. It was Irene, eyes intent and mouth askew. “It’s like I’m off your radar screen in one swift sweep.”

  “I’m…”

  “Working. Too much—for what you get.”

  “Y’know,” he managed, “art and science aren’t a lot different. Sometimes. Takes concentration.”

  “Art,” she said, “is answers to which there are no questions.”

  He blinked. “That sounds like a quotation.”

  “No, that was me.”

  “Uh, oh.”

  “So you want a quick slam bam, thank you Sam?”

  “Well, since you put it that way.”

  An hour later she leaned up on an elbow and said, “News.”

 
He blinked at her sleepily. “Uh…what?”

  “I’m late. Two weeks.”

  “Uh. Oh.” An anvil out of a clear blue sky.

  “We should talk about—”

  “Hoo boy.”

  “—what to do.”

  “Is that unusual for you?” First, get some data.

  “One week is tops for me.” She shaped her mouth into an astonished O. “Was.”

  “You were using…we were…”

  “The pill has a small failure rate, but…”

  “Not zero. And you didn’t forget one?”

  “No.”

  Long silence. “How do you feel about it?” Always a good way to buy time while your mind swirled around.

  “I’m thirty-two. It’s getting to be time.”

  “And then there’s us.”

  “Us.” She gave him a long, soulful look and flopped back down, staring at the ceiling, blinking.

  He ventured, “How do you feel about…”

  “Abortion?”

  She had seen it coming. “Yes.”

  “I’m easy, if it’s necessary.” Back up on the elbow, looking at him, “Is it?”

  “Look, I could use some time to think about this.”

  She nodded, mouth aslant. “So could I.”

  Ralph had asked the Bologna group—through his old friends, the two Fantis—to take a scan of the location. They put the Italian ’scopes on the region and processed the data and sent it by internet. It was waiting the next morning, 47 megs as an zipped attachment. He opened the attachment with a skittering anxiety. The Bologna group was first rate, their work solid.

  On an internet visual phone call he asked, “Roberto, what’s this? It can’t be the object I’m studying. It’s a mess.”

  On-screen, Roberto looked puzzled, forehead creased. “We wondered about that, yes. I can improve the resolution in a few days. We could very well clear up features with more observing time.”