The Sunborn

by Gregory Benford

  Mars never had. She wasn’t young anymore, for sure, but there were moments when she still felt youthful jolts of inexplicable exhilaration, energy mixed with yearning, a certain simmering sense of invincibility. Maybe it was Mars. Here you needed rugged confidence, or else you’d cower in your hab, afraid of the whole wide world outside. So she and Viktor had developed their own aspirations, steady like a faith that did not need expression, a hope that could sting like chlorine.

  Without Mars, she knew she would never feel that way again.

  Daphne found Julia, intersecting her in one of the subsurface corridors. “Hey, got some results,” Daphne said brightly.

  Julia blinked at her. The Vent R descent seemed like an age ago, though it was only a week. “Uh, great.”

  Daphne’s “office” was a tiny compartment. They wedged in as Julia reflected on the comparatively vast spaces she and Viktor occupied. “We got a good long way down, over a klick,” Daphne said. “Into side channels, too.”

  On the wall a satellite photo appeared, overlaid with blue lines. “Here’s the subsurface map. Got most of it with those climbing ’bots we took down.” The lines followed a jagged but mostly radial pattern, fanning out from the Vent R mouth. “And now we add the magnetic field data, waves emitted from—”

  Orange lines appeared. They were broader, mostly patterns of cross-hatching. “They follow the mat,” Daphne concluded triumphantly. “Not perfectly, but close enough that it can’t be an accident.”

  “Striking.” Julia peered at the cross-hatching. “The magnetic waves, the low-frequency emissions Viktor has been working on—this is where they come from?”

  Daphne was a biologist like Julia, but Mars staff had to be versatile. She said, “I know, I can’t see any reason why they should overlap—but they do.”

  Julia smiled. Daphne was a lot like her younger self, plunging ahead. “So the mat uses electromagnetism, too?”

  Daphne traced with her fingers some of the lines, thinking, not answering right away. “Seems unlikely, doesn’t it?”

  “Evolution is inventive.”

  “There are electric eels that use charge to find and shock prey. But waves…” Daphne shrugged. “What’s that saying of yours?”

  Julia wondered if the staff thought of her and Viktor as pontificator has-beens. Then she realized that, indeed, she did have stereotypical remarks. Like “Correlation may not mean causality?”

  “Yeah, that. I remember hearing that the disease rate in Europe goes up with temperature. But it’s the insects carrying the diseases that respond to temperature, get more active—not the weather making people sick.”

  “So the mat may not respond to magnetic fields directly?”

  Daphne spread her hands. “Sure, I—”

  “But then, what blew our capacitor?”

  Viktor called her, and she found him collapsed on their bed. “You’re overdoing it.”

  He ignored her. “Got a squirt from Earthside, mysterious.”

  “Axelrod.” Not a question.

  “Assistant to him. Said the moon antenna system launched a powered sail toward us.”

  Julia sat on the bed and felt his brow. Maybe a little warmer than usual. “This soon? I thought they weren’t going to have the power transmission system up and running for years.”

  Viktor thumbed on their wall screen. A deep-space picture, magnified to the limits of resolution. A silvery disk hung in the black. Below it, hanging by struts like a spiderweb, was a small golden package. “To boost this lightweight package to high velocity takes only a few antennas. Axelrod said to send this as test package.”

  Julia had paid little attention to the grandiose Consortium plans. The collision between global climate change and rising energy demands was the biggest international issue Earthside. Storms were wrecking cities, the ocean was lapping at dikes, Kansas was a desert and India had floods. Yet the cheapest path to prosperity was to burn cheap coal and let somebody else worry about the accumulated carbon dioxide in the air. A classic tragedy of the commons—profit was private, waste was communal.

  And here came the Consortium to the rescue. Viktor’s next picture showed the beginnings of the microwave antenna network Axelrod’s web of companies was building. Eventually it would trace around the moon’s disk, as seen from Earth, because that gave the highest focusing of the incoming microwave beams. Those beams would strike football-field-sized receivers, just chicken wire really. The induced power in those wires would feed directly into Earth’s power grid—cheap electricity.

  The original power would come from the harsh sunlight hammering at the moon’s surface. Captured in huge solar panels, fed to the microwave antennas, the energy source would be in its way an environmentalist’s dream: the environment affected would be a quarter of a million miles away from Earth.

  But that was a decade in the future, at least. Robots were making the solar panels on the moon, extracting iron from the lunar regolith with magnets, making wiring from it, building the antennas. Nearly all raw materials they got from the moon itself. Julia hadn’t even realized that they had any of the big lunar antennas up and running, but there they were—big wire cups on slender stalks, light in the lunar gravity. They pointed skyward and radiated power to the silvery sail.

  “Pushed it out of orbit around moon,” Viktor said, thumbing through more images of the sail. “Gave it speed. Sent it into long orbit for Mars.”

  Julia arched eyebrows, impressed. “Nice toy demo, but—”

  “Its job, they say, was to get here before that big nuke.”

  “Huh?”

  “Nuke had already left when Axelrod decided to send this,” Viktor said. “To beat its time in getting here.”

  “Why?”

  “That is the mystery.” Viktor grinned, though she could see he was bone-tired.

  “Just showing off, I bet.”

  He waved this away. “Squirt from Earthside says not. Axelrod wants me to pick it up when it aerobrakes.”

  “What? Why—wait, you can’t do it.”

  “Orders.”

  “You’re in no shape—”

  “They said we should both get it. For our eyes only.”

  He grinned, always happy when intrigues got more complicated.

  “When’s it get here?”

  “Two days. Sail burns up on entry. Payload chutes down. Trying to set the package—that little golden-wrapped thing, you saw?—down in Gusev.”

  “Three days before the nuke.” Julia frowned. “Damned funny.”

  “I like mysterious.”

  6.

  LAST TRAIN OUT OF DODGE

  TO KEEP HER MIND off their situation, she puzzled over the Vent R incident. Science beat politics every time.

  Viktor had pointed out the biggest clue: the correlation between water vapor pressure near the site and the magnetic waves.

  Except for birds who used the magnetic field to find their way on migrations, Earthly life mostly ignored magnetism. A few bacteria carried minute bits of iron and appeared to orient in a magnetic field, but how it helped them was unclear. She shook her head; would evolution have produced the same answer to the riddle of survival on Mars as on Earth?

  She sat and thought and watched the Martian landscape as sharp shadows stretched across the afternoon. A thin filament of cloud towered in the distance. Sure enough, it was in the right direction for Vent A. The mat was opening its thick seals again, following a pattern no one had deciphered yet. She added one more data entry to her slate; this was the first venting in several months. And nobody knew why the mat did it, though there were plenty of theories. Vapor pressure…

  The early discovery of methane in the Martian atmosphere, at ten parts per billion, had suggested that life might be the source—but it was not a clear proof. Scientists could always rummage around and find other interpretations, which in turn suggested further tests, and that was the dance of science itself.

  Maybe a recent volcanic eruption had vented the methane fr
om the warm interior; that happened often on Earth. Or perhaps, since comets were known to have methane ices, one had blundered into the atmosphere. And a calculation showed that the water vapor in the Martian atmosphere, kindled by ultraviolet, could react with the methane and erase it in a few centuries. So any volcanoes or comets had to be recent events. But in the hundreds of thousands of orbital photos there seemed no clear evidence for recent volcano ventings, or impact craters from comets. So the issue had drifted along without clear, sharp confirmation for any view. Until the Marsmat discoveries.

  Now they knew that the Marsmat could send signals over great distances, hundreds of kilometers at least, far larger than any single mat. They had seen that in Vent R, when the humanlike image shaped up out of the mat on a first visit.

  Why communicate over such scales? To sense a coming pulse of hydrogen sulfide vapor from deep below, tell the entire network, and make ready? A clear survival value in that, she supposed. Could organisms evolve such detailed response in this harsh place? Could an Earthly biofilm do it? Maybe biologists had never noticed. On Earth mats like the stromatolites were considered to be early, primitive forms with severe limitations and no future. The biofilms had just been outrun by other forms in the rich, warm, wet oceans.

  Julia went out to the big greenhouse and gardened to clear her mind. They all went to the greenhouse when they were tired of the endless sunset hues of Mars. Or when they longed to see something alive that wouldn’t talk. That first whiff of greenhouse air was a great morale boost. Greenhouses processed air better than any filter, carrying a particular fresh scent unlike Earth, undefinable, more raw. She would miss it.

  She barely nodded to others working. Privacy was precious, and they’d adopted the Japanese habit of not intruding on one another’s space unless by mutual agreement. She skipped the fields of wheat, rice, and potatoes, various beans, lines of broccoli and tomatoes. These looked ordinary, and then she walked under the canopy of carrot stalks so green they changed the Marslight.

  No one could predict what the combination of low gravity and low sunlight would do; some crops died, others became green gushers. There was something very calming about being surrounded by green leaves and vines, all nodding gently in the endless updraft. To strengthen trees and stalks, they had to run breezes, fake winds. She recalled how, in the early years, she and Viktor had taken advantage of the absence of others, off on rover trips, to make love amid the churning plants—exciting, though chilly. It’d always been a big turn-on for her to look over the shoulder of a lover into the swaying foliage of a tree. Viktor said it showed she was a real primitive.

  She worked with her hands to free her mind—pruning, harvesting, helping. Even a biologist had to keep reminding herself that life found ways nobody could foresee. Growing up in Australia, she had marveled at lizards in the deserts that absorbed water through channels in their feet, because they were most likely to come across moisture in shallow damp spots. On the other hand, nature made its creatures narrow of purpose.

  Silently she joined a team that was harvesting corn. It was good, solid work, letting her hands go and have fun while her mind could idle, running on its own. Cut, sort, bag…

  One winter she had gone out on a Girl Scout trip, and they had stayed overnight in a bush farmhouse with a tin roof. In the night birds thumped heavily onto the roof, because when they looked down from their migrating patterns, it reflected the moon and so looked like an inviting pond. She had rushed outside and found dazed ducks, given them water, and off they had gone—no doubt to make the same mistake again, because nature saw no point in giving them the processing power to learn from experience, much less to tell others of their kind. If there had been many tin roofs, they would never have made the migration, never made new ducks. Nature had not made them too narrow, not this time.

  Too narrow… Could evolution have found a way to give the mat some use for the magnetic field waves? It sounded crazy.

  Julia was thinking so hard about this that the burst of hand-clapping startled her. When she brought in a bushel of picked corn, her coworkers applauded. “Fastest picking I’ve ever seen,” a man said. Julia was startled. She had not even noticed.

  Sitting in the cafeteria, nursing a cup of coffee, a young woman from the bio section asked, “Mind if I sit down?” The room was crowded. Julia waved her into a chair. Stephanie, she recalled, a biochem type. They had even been on a dozen-author paper together, on how the Marsmat used sulfur for energy.

  “Nothing much to do,” the woman chatted on. “I’m a sexile for the next few hours.”

  “Uh, what?”

  “Exiled for sex. My roomie has a guy in.”

  “Uh, oh.” At first Julia blinked, affronted at this sudden bolt of intimate detail. Then she realized that this was another effect of living in a tight little base, however grand the views were outside. Unavoidably, formal hierarchy dissolved under the rub of informal daily life. See the commander daily slurping coffee and washing dishes, and pretty soon he doesn’t look like the leader anymore. Even legends did scut work—or should.

  The woman started happily chattering, and her talk went in Julia’s ear and out the other. Only when the other woman started to notice did she make an attempt to respond. Julia was busy realizing how out of touch with the younger staff she was. Could Praknor be right? Time to hang it up?

  Praknor tried to put her foot down over their excursion, eyes flashing. “No, it’s ridiculous.”

  “Axelrod said we are to recover package,” Viktor said.

  “You can barely walk!”

  “I’ll do the walking,” Julia said. “The route is along one of our standard drives, and I can do the driving, too.”

  “It’s twenty-three kilometers—”

  “We leave at dawn, back in plenty of time.”

  Praknor sat very still. “I believe we must define just who is now in charge here.”

  Julia said in a deliberately conversational tone, “Well, I hardly think it’s a dichotomous choice. Still, no need getting our knickers in a twist when we can defer to Earthside on this one, eh?”

  Earthside would be very surprised to be asked; tight control of excursions had faded away years ago. But she was counting on the fact that Praknor was so green she didn’t know what the routine was.

  Viktor picked this up. “And can talk to staff, too.”

  Praknor sputtered, but Viktor’s intuition proved right. The staff would support the venerable Marsnauts, not a fresh manager who hardly had her Earthside smell worn off.

  Julia sent a long message to the Consortium, and Praknor wrote one even longer. Off these went. Experience proved the rule: Earthside dithered for hours. Praknor got distracted with work. Nudge nudge, wink—

  So they went. It helped that everybody was talking about the new results from the Pluto expedition, and a bit distracted. Nobody asked questions. The ISA discovery of a biosphere there had electrified them all. Julia had no idea what to think about the Pluto reports. The biology seemed impossible. But then, so had the news that the solar system’s bow shock was moving inward. She had long before learned to let the outer world go on, without her attention. She put aside everything and focused on the task at hand—always, on risky Mars, a good idea.

  Going out, Julia noticed how much of the landscape was now rutted and marked by the ever-busy humans. She could see the towers of their water-drilling fields in the distance. Some pingos nearby were thoroughly excavated, both for bio-signatures in the deep ice deposits and for geological data; then the ice was harvested, leaving holes yawning like mouths. Not far from them was the crumpled descent package.

  This was yet another miracle of design. Hardly the size of a coffee table, the smart, carbon-fiber shell had survived the blistering plunge by flying itself. Stubby wings let it use the infalling energy to bank and lift, gaining the time to locate Gusev. Viktor insisted on parking only meters away, so she had a very short walk. The announced reason for this flight was some vital small parts for a ma
lfed pressure control system, and they were indeed most of the payload mass. But when she lifted the parts out, there was a cylinder at the back. On it in big stenciled letters was FOR JULIA AND VIKTOR ONLY. In Axelrod’s hand.

  She got it back into the rover, and inside was a rolled-up letter. “It’s so like Axelrod to send an old-fashioned letter rather than an electronic squirt,” she said, opening it.

  “Hang the expense,” Viktor said. “Is also much more secure this way.”

  They read it together. “Now will be much fun to talk to Praknor,” Viktor remarked.

  “I can’t believe it,” Praknor said.

  They showed her the letter. Axelrod had even written it by hand; he never trusted the security of digital media and more than once had been proved right. Praknor read it over twice.

  “The big nuke is for heavy Mars hauling, yes.” Viktor began, as usual, by illuminating the tech angle. “Will land with plenty supplies, rovers, support gear. Rut will take off with water in holds.”

  “This is insane,” Praknor said quietly.

  “Maybe, but is orders.” Viktor even smiled.

  “I thought, I was told, I was to prepare you for transfer to the moon. But, but—to send you to Pluto!”

  “They need help,” Julia said. “Nobody there has experience dealing with alien life, communication—”

  “And you…”

  Praknor didn’t finish her sentence, but Julia knew how it went: You over-the-hill types are going to ride out there in the biggest, best nuke yet built, to help? When young people like me are available? Ah, the arrogance of youth!

  “We are only part of it,” Viktor said crisply. “This nuke has crew, supplies needed on Pluto, just needs us for maybe helping with the communication problem. And Axelrod, he has money in his mind, too.”

  Praknor shook her head. “There’s no money to be made at Pluto. That’s an ISA expedition.”