Authors: Greg Egan
Tags: #Science Fiction, #General, #Space Opera, #Fiction
“I wish we had some way to pin down the distance,” Roberto lamented.
“Do I detect a hint of parallax envy?” Tamara joked. On the home world, astronomers had had it easy: wait half a day and your viewpoint moved by the planet’s width; wait half a year and that became the width of the orbit. Once those baselines had been measured, the shifting angles they created had been revelatory. But whether you imagined it was the
Peerless
itself that was moving day by day, or the Object, without knowing the relative velocity to fix the baseline between successive views the most you could glean from the angles alone was the timing of the encounter, not the distance.
Roberto hummed with frustration. “This thing might come close enough for us to resolve its shape—and maybe even structural features, impact craters… who knows? Think how much more valuable all that would be if we knew their scale!”
Ada said, “It sounds like the perfect job for an infrared color trail.”
“What kind of gratitude is this?” Tamara demanded. “I bring my two friends the find of a lifetime, and all I get are fantasies about how things could be better!”
Ada was indignant. “What fantasy? I’m serious! The chemists have never made infrared a priority before, because they’ve never had a good enough reason.”
Chemicals sensitive to ultraviolet light had been known since before the launch, but no one had managed to achieve the same feat at the infrared end of the spectrum. Imaging a slow-moving object’s color trail in ultraviolet wasn’t all that helpful; even infinitely fast UV would lie closer to violet in the trail than violet was to red. But an infrared trail could stretch out to many times the length of the visible portion.
“And this will count as a good reason?” Roberto was amused. “The last time I asked for a favor from the chemists, I was told to wait until they’d solved the fuel problem.”
Ada said, “Maybe we can find a chemist who’s itching for a break. If you’ve spent half your life bashing your head against the same old problem, why not try something easier?”
“No, they all want the glory too badly for that,” Roberto declared. “Who’s going to waste their time inventing
infrared-sensitive paper
when they might be on the verge of inventing a way home?”
Tamara tried to put herself inside a chemist’s skin. The
Peerless
’s reserves of sunstone, burned in the usual manner, would barely be enough to bring the mountain to a halt, let alone carry their descendants back to the home world. She’d understood that unsettling fact since childhood, but to someone who’d made the fuel problem their vocation what interest could there be in the astronomers’ petty concerns? The orthogonal cluster and the debris that surrounded it were just obstacles to be avoided, and while gathering statistics on the distribution of this hazard was a worthwhile activity, it wouldn’t take an infrared color trail to recognize a head-on collision.
Then again, surely every chemist was at least a little curious as to how the sprinkling of orthogonal dust that had adhered to the surface of the
Peerless
had threatened to set the rock on fire, in the days before spin. Tamara wondered if she could sell them on the notion that establishing the size of any craters on the Object might shed light on that mysterious reaction. The trouble was, any ordinary rock that
had
struck the Object would have done so at such a great speed that the most likely result would have been, not a crater, but an all-obliterating fireball. The
Peerless
itself was almost certainly the only ordinary object in the region that had ended up more or less matching velocities with the orthogonal material—and if a leisurely encounter between the two kinds of matter was ever to be repeated, the
Peerless
would have to be involved again.
Tamara looked up at her friends and realized just how blind she’d been. Roberto had been right to refuse to accept the same old regime of half-useless observations; Ada had been right to insist that there could easily be better methods within their reach. But all three of them had been too timid by far.
Tamara said, “Why don’t we go there?”
Roberto blinked. “What?”
Ada emitted an excited chirp. “You mean start the engines and…?”
“No, no!” Tamara cut her off. “The
Peerless
is too big and unwieldy, and it would be insane to waste that much fuel. We should build a smaller rocket, just for this journey—something we can take as close to the Object as we dare. Then we can measure what we like, observe what we like… carry out experiments, maybe even bring back samples.”
Ada held up her navigator’s manual, regarding it with an almost fearful new respect. When Tamara had studied the same notes, she’d assumed that the only use she’d ever make of them would be to teach the theory to the next generation, keeping the knowledge from withering away while they waited for the infinitely remote prospect of commencing the journey home.
Roberto’s stunned expression gave way to one of pure delight. “If the tiniest speck of orthogonal rock is a liberator for calmstone,” he said, “who knows what the same material in bulk could do to our fuel?”
Tamara said, “I think we might be able to interest the chemists in helping us find the answer to
that
.”
3
C
arla opened the valve at the top of the lamp, allowing a trickle of liberator to fall onto the sunstone. She started at the sudden hissing sound and the dazzling eruption of radiance, and her hand moved quickly to the dousing lever that would bury the flame in sand. But after a moment the noise settled to a steady splutter, and though the beam escaping through the aperture in the lamp’s cover retained its formidable intensity, it appeared to be stable.
Carla had prepared the liberator herself, extracting the active ingredient from sawflower roots, then diluting it with crushed powderstone, checking the proportions three times and running the mixture through an agitator to be sure there were no clumps. But even these precautions couldn’t assuage her fears entirely. Fire of every kind crossed the Cornelio line into positive temperatures, but the act of igniting sunstone felt like summoning a malevolent creature out of the sagas. It might sit on the bench and amuse you with its tricks, but you knew that what it really wanted was to bring its whole world of bright chaos through the crack you’d opened up between the realms.
A lens over the lamp’s aperture partly countered the natural spreading of the light. Carla placed a small mirror in its path; mounted diagonally on a pegged holder, it sent the beam straight down through a hole in the bench-top. She knelt and fitted a triangular prism into place to intercept the vertical beam, then she ran an upturned hand through the space below it, to watch the brilliant spectrum glide over her skin. Sunstone disquieted her, but no other source produced such pure, intense colors.
A robust clearstone container sat on the floor beneath the bench. Apart from the corners, rounded for strength, it was almost box-like in shape, and the gravity here was strong enough to hold it in place by friction alone. At the bottom of the container was a flat rectangular mirror, freshly polished. The spectrum from the prism fell along the length of the mirror, with a thin strip of colors spilling off one edge onto a sheet of gridded paper, making it easy to see the position of every hue. Carla noted the locations of the red and violet ends; some space remained beyond them where the mirrorstone would be exposed to invisible wavelengths. Half of the spectrum reflecting off the mirror showed up on the underside of the bench-top, with the rest reaching an adjacent wall, but Carla felt no urge to contain the spilt light. It was no longer part of the experiment, and the streak on the wall made a cheerful decoration.
The prism she was using had been calibrated against a light comb by an earlier custodian of the workshop—the neatly written table was dated just a dozen and four years after the launch—allowing her to assign a precise wavelength to each line on the grid. She verified the overall calibration with half a dozen spot checks, then glanced at the clock. Going on what Marzio had told her, and accounting for the strength of the beam, she had planned for an initial exposure of one day.
Marzio was one of the most respected instrument builders on the
Peerless
. Four years ago, he’d been asked by the astronomers to construct a wide-field camera that could function in the void, in the hope of capturing sharper images than those taken behind the clearstone panels of the observatory domes. Like most such cameras his design had included a mirror to divert the light path, making it easier to keep the gas that activated the sensitized paper from leaving a residue on the lens. The device he’d built had been successful enough, but when Carla had run into him recently he’d told her something curious: the mirror had grown tarnished more rapidly than the corresponding part in any camera he’d built before. This was not what anyone would have expected; the gradual loss of reflectivity in polished mirrorstone had always been attributed to some kind of slow chemical reaction with the air.
Marzio had speculated that perhaps the activating gas, which seemed to cause no problems with the mirrors in air-filled cameras, was behaving differently in the vacuum—although it still did its job perfectly well. And the tarnish on the mirror, he admitted, bore no signs of being an entirely new phenomenon: it was indistinguishable from the patina that appeared under ordinary conditions. It merely arrived sooner in the absence of air.
Carla had had no good theories about any of this, but Marzio’s observation had nagged at her.
If it wasn’t air that tarnished mirrors, what was it?
Exposure to light, or simply the passage of time? It would have been absurd to ask Marzio to build a whole new camera for her to play with, so she’d set up this simple test. To measure the effect of time alone, a second mirror in its own evacuated container had been shut away in a light-proof box.
Carla stood by the bench, eyeing the lamp warily. She’d had to beg Assunto to approve the use of sunstone, though this handful was nothing to the quantity the
Peerless
’s cooling system burned up every day. “What’s the purpose of this experiment?” he’d asked irritably. He’d have to justify his decision to the Council in person at the next meeting, so he needed as pithy a summary as possible.
“Understanding the stability of matter.”
“And how exactly will a tarnished mirror help with that?”
“If the surface of a mirror can change in a vacuum,” Carla had argued, “that’s not a chemical reaction, it’s something simpler. If the luxagens in the mirrorstone are rearranging themselves in response to light, that could provide us with a
mildly
unstable system that we’d have a chance to manipulate and study—”
“As opposed to the kind that explodes in your face.” Assunto was of the school that believed luxagens would turn out to be pure fiction—he preferred to think of matter as a continuum rather than a collection of discrete particles—but in the end he’d signed the requisition for six scroods of sunstone.
Carla had re-read and signed the safety regulations. A sunstone lamp could not be left unattended. She went and stood at her desk, but kept her rear eyes on the lamp’s fizzing crucible as she marked her optics students’ assignments. After the first half-dozen it was tedious work, but she forced herself to wait as long as she could before taking a break.
Carla had been told that she’d have to share this cramped workshop with Onesto, the archivist, until one of the senior experimentalists in the main facility retired and freed up a bench there. But she and Onesto usually managed to choose shifts with as little overlap as possible, to avoid disturbing each other, and there were advantages to working on her own.
When the clock struck the fourth bell she stopped to wind it, then she went to the cupboard and took out a bag of groundnuts. She cupped one hand and tipped three of the aromatic delicacies onto her palm, then closed her fingers over them to trap the exhilarating scent. Her whole body tingled with anticipatory pleasure, casting off the lethargy that had begun to afflict her. But Carla had the timing down to an art: just before the muscles in her throat threatened to start gulping down an unsatisfying emptiness, she tossed the nuts back into the bag and quickly returned them to the cupboard.
I did swallow them
, she told herself, wiping her hand over her lips, slipping three fingers into her mouth.
That’s the aftertaste.
She picked up the stack of assignments again, then glanced back over the ones she’d marked so far. The men were doing better than the women, she realized—not by a lot, and not in every case, but it was impossible to miss the pattern. Carla thumped the side of the desk angrily; the lamp three strides away hissed and flickered in response. After seeing so many women slip behind in her final year, she’d promised herself that the same thing wouldn’t happen to her own students. She always pushed the women in her class to participate, to ask and answer questions so they couldn’t glide through the lesson in a hunger daze, but she was going to have to pay more attention and pick out the ones who were losing focus.
The ones who might be headed where Silvana had gone.
“Yeah,” she muttered. “Then I’ll hand out bags of nuts. Problem solved.”
“Are you sure you’ll be all right with this?” Carla asked Onesto.
He looked over the apparatus, respectful but not intimidated. “If in doubt, I’ll just kill the flame,” he said, gesturing at the lamp’s dousing lever. “You can always complete the experiment with a second exposure, can’t you?”
“Of course,” Carla replied. It was kind of him to agree to take responsibility for the lamp; she could have enlisted one of her students, but since Onesto was going to be at his desk a few strides away regardless, it did make sense.
“Are you seeing your co tonight?” he asked, doing his best to make it sound as if he viewed the question as nothing more than ordinary small talk.
“In a couple of days.” Carla had been open about the arrangement; she was hoping more people would try the same strategy, but most of her colleagues had greeted the news with embarrassment or confusion.