The Frozen Sky Read online

  Vonnie’s friends might have stayed in the trench all day, absorbed in their chem tests and new theories. They might have been satisfied with this discovery and stayed until the other ships arrived.

  She was the one who convinced them to move on.

  “Why don’t you two quit playing with that guck and help me,” she said, laughing. “Let’s go.”

  9.

  When she started down the tunnel, it was with the thrill of history. Her exhilaration felt like a shout. She would always be first to walk inside Europa, and a slavecast kept a swirl of relays and burrowers around her feet, recording everything.

  She wasn’t as graceful as the mecha. The passage dropped steeply. Misjudging the gravity, she tended to bash into the ceiling. Then the opening shrank until it wasn’t much bigger than her suit. Again and again, Vonnie was forced to drop to her knees or roughly shoulder through.

  Her telemetry betrayed them. The men on the radio questioned her movement and ordered her back. She kept going. Sonar showed an end to the tunnel after four hundred meters, yet infrared revealed that the end was a shade warmer than its surroundings. Hot pinpricks of gas were bleeding through.

  “There’s something on the other side,” Vonnie said. “My sensors are going nuts.”

  “Something alive?” Lam asked.

  “Stop,” the radio said. “Specialist Vonderach, acknowledge. You will comply.”

  “Roger that,” she said. “But this is an air lock. Look at it. It’s too smooth. It definitely isn’t a formation caused by melt or tidal pressures.”

  She cringed at the idea of giving such responsibility to anything as flimsy as ice, but there were no metals here. What else could the carvers use? It spoke again of their inventiveness and determination. She couldn’t wait to see more.

  Opening the end of the tunnel was a chance to show her worth to the team. To get through without losing the air, Vonnie would need to trap herself between the lock and a new seal of her own making — and every surface in the ice showed old scars and stubs. Irregular holes marred the walls where building material had been dug out and replaced.

  “I say ’go,’” Lam told the men on the radio. “We’re picking up too many readings. Noise. Heat. We could miss something significant if we sit here.”

  “I can get us in,” Vonnie said.

  The debate among the high-gee ships was maddening. The Brazilians wanted her to withdraw. So did Naomi Harada, the Japanese minister aboard the American craft.

  “What if our guys listen to them?” Vonnie worried, but Lam said, “No, Brazil is doing our work for us. Watch. Nobody likes being told what to do.”

  He predicted the chain of events flawlessly. The Brazilians were frustrated that they had none of their own people on Europa. Their demands for international unity were terse, even petty. They cited old grievances against NASA and the ESA. They called on China to support them.

  Ignoring their objections, the leaders of the Chinese, American, and European space agencies reached a consensus: Vonnie should continue.

  “Yes!” she said, pumping her fist in excitement.

  Lam grinned at her like a kid.

  They gathered near the air lock. Bauman was last in line, so Vonnie took control of Bauman’s suit, assembling frozen hunks in a stack and soldering the pile together with her laser finger on a minimum setting. “Slow work,” she apologized, not wanting to dull their energy.

  Lam shrugged, running sims on his visor as he waited. “Think what the carvers used instead of a laser,” he said. “Body heat? Urine or saliva? There are organic contaminants everywhere.”

  “Lots of DNA,” Bauman agreed happily.

  At last they were sealed in. Vonnie eased through the original lock and saw another ice plug further on. Redundancy was good engineering, but she was disappointed to realize how many lifetimes it must have been since the carvers had visited the tunnel or even considered it important.

  Long, long ago, the top of the next air lock had slumped open. Her suit analyzed the low-pressure atmosphere wafting past her as 98.9 percent nitrogen, a gas so inert that no creature could have evolved to burn it as an energy source. This seemed to be a dead area. Why bother to block it off?

  “There’s nobody home,” Vonnie said.

  “Knock knock.” Lam was cheerful, even buoyant, bumping her arm as he tried to look past.

  “Maybe the air is bad because this tunnel is unused,” Vonnie said. “Oxygen could be their most closely guarded resource. They might control it with flood gates.”

  No answer. Lam and Bauman were beyond listening to her, lost in the chatter of data. Their tiniest mecha had run ahead while others lingered to examine the ice. Lam especially was in his element, pulling files and fitting each perspective into a working whole.

  Vonnie was eager, too, yet she meticulously rebuilt the locks behind them. Then she moved in front again.

  After another eighty meters, the slanting tunnel dropped into a sink hole. The vent was encrusted with old melt. Across from her was a hollow of uncertain depth. Stalactites hung from the top of the shaft.

  There had been a catastrophe, probably a belch of heat. If the carvers had built anything else in the area, it was gone, but Vonnie couldn’t feel sad.

  She walked to the edge of the hole. Her sonar raced down the shaft like a fantastic halo, never reaching bottom. The hole appeared to drop for more than a kilometer, twisting, widening, and branching away.

  Somewhere down there was the dark heart of Europa.

  “Perfect,” Bauman said. “This sink hole is a natural cross-section through the ice. How far down can we take samples?”

  “Give me a minute,” Vonnie said. It would be easy to secure a few bolts, play out a molecular wire, and let their mecha descend like spiders. She rifled through her tool kit.

  “Huh,” Lam said, taking control of a burrower near Vonnie. The machine scooted away from her and joined him.

  “What’ve you got?” she asked.

  “I—”

  Later, Vonnie played back their group feed. Cursing him, she understood. His radar had probed a swath of dirty ice in the tunnel wall. Most of the patches that interested him were impure. Some were stained with lava dust, others discolored like milk or glass.

  He’d noticed a shell — a small, spiral shell lodged in the wall of the tunnel. It wouldn’t have looked unusual on any beach on Earth. On Europa, it was a treasure.

  Lam’s suit had reported the shell’s position to their grid, but he couldn’t leave it alone. He needed to be involved. Under his guidance, marking the shell for retrieval, their burrower stabbed a radio pin into the wall.

  The ice exploded with black rock.

  Vonnie was standing beside the largest mass. Somehow that saved her. The burst of ice and rock knocked her upward, although she was snarled in her wire.

  Bauman yelled once: “Lam, get back!”

  There was probably no more than a quarter ton of debris stopped up behind the dust pack, a collection of gravel and stones that had gradually sunk into a loose, dangerous bulge. It weighed a thirteenth as much as it would have on Earth, but in this gravity, it splashed.

  It tore apart the sink hole. Other veins of rock caused a vicious swell. The heap rose, spread, and settled again like a cloud.

  Vonnie escaped the worst shockwave, half-conscious and confused. She was thrown to the top of the vent as her friends disappeared. Their sharecasts clamored with alarms and one massive injury report before their suits went dark. But she was tied to the wire, and it would not break. One end caught in the heaving ice.

  Then the avalanche took her, too.

  10.

  The first pocket world in the ice would always be her favorite. It was inhabited by two peaceful species of bugs which were related to each other, yet were unlike the fat-bodied ants brought up by the ESA rover. They seemed to feed solely on the gray bacterial mats that grew alongside the wells of a hot spring, where the melt was thick and ever-changing.

  On
ce upon a time, this chamber must have been part of more expansive catacombs. Ice-falls had long since closed it off. Vonnie had only stumbled into this dripping space when she refused to be deterred and started digging.

  Her mind had felt very, very small in those hours — too small for any thought except to get away from the lethal, creaking weight of the collapsed vent above her.

  Deep radar let her identify load-bearing sections in the ice. She’d climbed, cut, excavated and squirmed from one miniscule safe zone to another, using her arms like shovels, numbly reaching forward more times than she could count. Her knees and belly ached from contorting through the gaps.

  She remembered listening for every groan and crack in the ice. She remembered the red bar of an alarm on her visor warning that her air reserves were at sixty minutes.

  Her endless crawl had stopped, perhaps forever, as she curled herself in a hole no larger than a coffin to rig an electrolysis unit from her tool kit. The job became her entire focus. She was in shock, and concentrating on an attainable goal was exactly what she needed.

  She assembled two electrode plates, a pump, and a compressor inside a slim steel box. She mounted the unit on her shoulder, then fed ice into the hopper, separating the oxygen from the hydrogen. Her cylinders recharged. And if her new air was contaminated, if there were Europan microorganisms or toxins in the ice, what choice did she have? Cooking the ice should sterilize any pathogens. Her screens showed no detectible sulfurs or dioxides. Nor could she smell anything peculiar.

  When she finally emerged into the pocket world, she was startled to realize how much time had passed. She’d been worming through the ice for the better part of an Earth day — nearly twenty hours.

  She wasn’t hurt except for a sprained elbow.

  She was alone.

  Not one of her comm links were active. The relays she’d left above the sink hole must have been scattered and crushed when the vent collapsed. Maybe she’d fallen further than she thought.

  The pocket world was safe, but she couldn’t stay. The other ships were seventy-five hours out and it would take them several more hours to gear up and scout for her, even longer to forge their way through the crumbling mass.

  She had to find a way back to the surface. She could continue to replenish her oxygen and water supplies from the ice, but she’d gorged herself as soon as she’d noticed her hunger. Her suit offered top-of-the-line meat dishes, pastas, fruits, and desserts like only the wealthiest people on Earth could afford, with the caveat that her meals were pastes fed from tubes inside her helmet… Now bulk was more critical than nutrition or pleasure. She would have traded every fruit pack and candy for more carbohydrates.

  Her remaining supplies might last eight or nine days, twelve at the outside. Before then, she would get weak.

  Could she eat the bugs?

  No, she thought. It wouldn’t come to that. It couldn’t. Besides, they might make her ill.

  She regretted not having beacons to leave in the pocket world. Bauman especially would have been enthused by the bugs, but most of Vonnie’s mecha were gone. She only had one left — a burrower — plus three miniature relays attached to her chest plate. She sent them exploring. Then she sat quietly, mourning and resting, even napping for three hours.

  Her camera lights were dazzling in the wet ice as she gazed through her visor, comforted by the use of normal light and vision.

  Discolored rimes of minerals permeated the uneven floor and walls of the cave. That meant the hot springs routinely overflowed. The bubbling water was saturated with iron and salt. It tainted the ice and poisoned the bugs, which avoided the most concentrated salt deposits.

  The atmosphere was oxygen-rich, although it was nothing that would support a human being, laced with hydrogen chloride. More interesting, the pressure was five times what she’d seen near the surface, due in part to a lower altitude but mostly because this hollow was self-contained.

  Neither species of bug had eyes or even the most primitive photo receptors. They used fan antennae and scent instead. They were basically helpless. Droplets fell steadily or in periodic rains. The chamber floor was pebbled with a thousand specimens sealed beneath the ice.

  Vonnie collected ten bugs from each species and put them in her chest pack, then added samples from the bacterial mats.

  The mats were vital evidence to prove the foundation of Lam’s evolutionary theory. It took billions of microbes to form something large enough to be seen by human eyes. These slimes grew in blots as fine as a needle point and as imposing as a stranger’s shadow.

  She thought she could identify three different strains. One reached into the air with tendril-like fuzz. Two commingled in a symbiotic relationship, possibly using iron and water for food. This pale muck had learned to expand from the hot springs onto the ice. Vonnie supposed it used layers of dead material as insulation. Maybe it fed from the melting surface.

  One thing was obvious. The bugs’ mortality rate, while high, wasn’t enough to keep them from outgrowing their food source. This pocket ecology was more than incomplete; it was unworkable; it was temporary.

  Vonnie was frustrated when she built Lam’s ghost to help her. Doing so was illegal, but she was beyond any concern except survival.

  Her first words to him were harsh. “Hey. Can you hear me?”

  —Online.

  “Your name is Choh Lam. You killed yourself and my friend because you couldn’t wait five damn seconds for an engineer to tell you not to bang on the ice.”

  —Consolidating files.

  “Never do anything again unless I tell you. Understood?”

  —Negative. What are my instructions?

  “I need to know where I am. Can you piece together my coordinates in relation to the surface?”

  —Negative. Further access to core systems required.

  “Goddamn it!”

  Throughout Europe and North America, combining human mem files with low-level AIs was forbidden. Organic minds were extensive, subtle, and predisposed to neurochemical and emotional imbalances. Failing to place the slightest piece of the puzzle could have severe consequences.

  Duplicating the living or resurrecting the dead also crossed ethical lines and medical considerations. In her childhood, thousands of court cases dealing with family, property, and tax laws had led to a widespread revulsion for electronic personalities. Many of them were distorted nightmares of themselves.

  Some cultures stood as exceptions. China and Korea permitted human-based AIs, keeping their ancestors with them. In the Middle East, there were immortal holy men.

  Vonnie didn’t have the computing power of those governments. Most of her suit’s systems were Level VII intelligences. Each one was a task-specific processor. Those subroutines accomplished intricate feats like her visor’s retinal response program and brute work such as balancing 220 kilos of armor in motion without falling over.

  If idle, each system functioned as spare memory. They were intended to draw on each other in crisis. By permanently linking a hundred subroutines, Vonnie created enough quantum memory to host a Level II intelligence with self-awareness and personality, but she was angry at Lam and afraid of dying in this impossible world.

  Bauman would have been a better companion. Vonnie wouldn’t have tried so hard to control her. The disaster she made of Lam was erratic because he was missing too much. She wanted him to be cautious, even timid.

  She didn’t trust the result.

  When her mecha reported a mild current of atmosphere 1.9 kilometers from the bugs’ home, Vonnie shut down the ghost. She called her mecha back to her. After they rejoined her, she attached the minis to her chest in their carry sockets and made sure the burrower was slavecast to her suit.

  She dug her way through old cave-ins and membranes of ice, following a conduit left by the minis. From their data, she knew there were more vents nearby.

  As she clawed at the ice, she felt another aftershock. Maybe she’d set it off by undermining a weight-bearing f
ormation. There was a ponderous groan. Then the ice heaved, slamming at her knees and chin. Her surroundings gave way and she fell tumbling into the white.

  “Help me!” she screamed. “Lam!?”

  —Online.

  “Stabilizers! Get my suit turned around!”

  Grabbing at loose hunks and powder, she couldn’t tell up from down. Huge pieces crashed against her. The rest of the avalanche felt like quicksand or a waterfall. It rushed and billowed, taking the burrower away from her. In seconds, the burrower’s signals faded.

  Her suit was equipped with gyroscopes, but her gyros were one of the systems she’d hacked to make room for the ghost. That was why she’d reawakened him.

  With his help, Vonnie located an enormous wedge. She clutched at it as the flowing ice pounded on her helmet and back. Radar indicated a house-sized slab. Unfortunately, it began to rotate beneath her weight. In a minute, maybe less, it would roll and dump her. She scraped at it with her fingers and boots, trying to keep her balance — trying to locate a bigger chunk — but her sensors were inundated with noise and motion.

  “Analyze my datastreams!” she shouted. “Which way should I go?”

  —What is your destination?

  “Solid ground. Anywhere.”

  —Where are we now?

  Certain she was in her grave, Vonnie gave him limited access to her mem files, enough to explain that the fallen vent where he’d died must have flattened out against the surrounding area, causing other networks to collapse. Now those implosions were also pushing down or sideways.

  The ghost handled this job well. Based on her data and current sonar readings, he created sims to predict the worst of the ice falls.

  Vonnie labored to free herself, sinking ever deeper through the mayhem. She struggled for nine hours.

  To keep up her stamina, she ate more than she wanted, barely tasting the venison-flavored protein or faux baked potato. Nonstop exertion also took its toll on her oxygen supply. Each bite, each breath, shortened the time she had left.

  Losing hope, a queer thought struck her.