Analog SFF, June 2011 (3 page)

"Two tethers,” Thad repeated. “Done. After you, Pearl."

Gabe pulled himself hand over hand along the cable, coasting above the inky surface. His eyes insisted he was soaring up a cliff face. Gravity's feeble tug told his inner ears he was falling
into
the cliff face. His gut wished eyes and ears would come to some agreement.

After twenty yanks Gabe stopped pulling. “Coasting,” he radioed the newbie.

"Thanks. The view from behind is unattractive enough without climbing up your butt."

Gabe slowed with gentle hand pressure against the cable at the first glint ahead of a piton anchored in the rock. Carefully he unclipped one carabiner and snapped it back onto the cable on the opposite side of the ring. He did the same with his second tether. He made sure Newbie followed the same fail-safe procedure before resuming the trip to sector twelve.

The surface lights, antennae, and trash dump of the station dropped behind the too-close horizon. But a status icon in his HUD shone a steady, reassuring green, confirming connectivity with Tina and the command center. The metal guide cable did double duty as an antenna.

Every hundred or so feet a piton interrupted their glide, and in such short increments they made their way toward sector twelve. After ten minutes Gabe checked in with Tina. Twice he saw survey robots—their silvery, octopoid shapes unmistakable—creeping along the surface. The second bot's instrument suite must have sensed a buried ice seam, because the machine was staking a radio beacon. Had Gabe cared to tune to the proper frequency, he would have heard soft beeping from the marker.

Ice meant water. Water meant oxygen and hydrogen. And water, oxygen, and hydrogen already in near-Earth orbit—not lofted from Earth's surface or the permanently shadowed polar craters of the distant moon at the cost of thousands of dollars per pound—were dearer than gold or platinum. So, too, whatever mineral wealth could be wrung from the rocks of Phoebe. On scheduled outings, he continued to survey for exploitable resources.

It was said: low Earth orbit is halfway to anywhere in the solar system. That was a metaphorical truth, almost poetic. Half the work of going anywhere in the solar system
was
expended fighting Earth's gravity. Building powersats with Phoebe's mineral resources, beaming down solar energy to an energy-starved world, would be only the beginning. Phoebe would be the gateway to the planets.

Away from the station the moonscape dissolved into a shadowy sameness. They passed the pilot distillery sited at a safe distance from the habitat. Parallel glints revealed pipes snaking across the dark surface, delivering water, oxygen, and hydrogen to the base.

Gabe played tour guide, pointing out the little world's interesting features. “On our left, the thermal nuclear rockets that nudged Phoebe into orbit.” He glanced at his Geiger counter, even though workers had long since recycled the uranium fuel rods in the base power plant. No matter how many powersats got their start here, Phoebe, forever behind its sunshield, would stay nuclear. “And on our right, the Grand Chasm. It's no great shakes by Earth standards, but relative to Phoebe, it's huge."

"Uh-huh,” Thad said.

Newbie had been moody since they left the station. As for what preoccupied him, Gabe could only guess. Maybe no more was at work here than that Thad—like most of the crew—was an engineer, without interest in Phoebe itself. When Thad deigned to interrupt the travelogue, it was always with practical questions. About pressure suits, their related gear, and how soon anyone would come after them if comm should break down . . .

Fair enough. Knowing the limitations and vulnerabilities of the equipment could save a person's life. Although Gabe wished he could share the excitement of discovery, the rocks were not going anywhere. Maybe Newbie would lighten up after he got more comfortable with his equipment.

They glided past the infrared telescope. Good, Gabe thought: we're halfway there. About all he understood about IR astronomy was that hot objects emitted infrared, so you wanted your infrared instruments kept cold to minimize their own intrinsic thermal noise. Behind its sunshield, Phoebe was about as cold as anywhere in Earth's neighborhood ever got. The ‘scope's cryocooler, powered by the base nuclear reactor, kept the IR sensor colder still.

He slowed or stopped whenever a surface feature caught his eye, but even a cursory look said most of these rocks were yet more carbonaceous chondrites and silicates. Two bits of stone he could not immediately identify went into his sample bag, for tests back at the station.

He
was curious about this tiny world, even if there was no point in discussing it.

Isotope dating of previous samples said Phoebe was more than four billion years old. So why did it still exist? Its desiccated, rocky crust was not
that
impressive as an insulator. Had it always followed the orbit in which it had been discovered, swooping inside Earth's own orbit, Phoebe's ice would have sublimated long ago, its rocky remains dispersed into a short-period meteor shower. Of course if it had always followed that orbit, the Near Earth Object survey would have spotted Phoebe years earlier. Or Phoebe would have smacked Earth before anyone even knew about death from the sky.

So Phoebe had had another orbit, an orbit more distant from the sun. Planetary astronomers had yet to work out Phoebe's original path and what planetary close encounter might have sent Phoebe diving at the Earth. Gabe guessed there was a Nobel waiting for whoever figured it out.

As the Earth waned and the landscape faded into darkness, he had Oscar project a topo map on his HUD. The blinking red dot had them most of the way to the green dot representing the stranded bot. Pits and ravines, ridges and rocky jumbles leapt out of the map image. He tugged his tethers once, twice for reassurance.

"Let's stop for a minute,” Gabe called. New Earth was imminent, and Newbie was in for a treat. “Watch the limb of the planet."

Earth's crescent became the thinnest of arcs, then disappeared.

A pale, shimmering arch—part rainbow, part oil slick—emerged from the darkness. Phoebe's sunshield. The free-flying Mylar disk that hovered above Phoebe warded off the sunlight that might yet boil away precious ice as boots and robot tentacles and, eventually, mining operations scraped through the insulating surface layers. The shield's sun-facing side reflected most of the light that hit it. What little sunlight penetrated the shield—the bit they could see—was scattered by the backside's granular coating.

For an endless moment the arch, large but faint, was the brightest object in the sky. Then the trailing edge of the shield, too, slid into the Earth's shadow, abandoning the sky to stars like chips of diamond.

Now the sole clue to Earth's presence was a hole in the star field. Even with eyes fully adjusted to the darkness, from this altitude Gabe could not spot any city lights. He could pretend that all was well below, that the world was not divided between energy haves and have-nots.

"Show's over,” Gabe said. He switched on his helmet lights. An instant later, Thad activated his own. “Pretty cool, though, don't you think?"

Thad only grunted.

"So, Thad. What
were
you making in the shop?” Gabe was just making conversation. Skimming the pitch-black rock face in the near-darkness was eerie.

He felt a tap-tap on his calf and twisted around. Thad had only one hand on the guide cable, waggling his other hand. Two fingers were raised.

"Oscar, private channel two,” Gabe ordered. “Okay, Thad. What's going on?"

"Private channel two,” Thad repeated. Finally, he added, “You'll keep this to yourself, right?"

"If that's what you want."

Hand over hand, they went. A rim of sunshield reappeared just before the Earth returned as a new crescent. Gabe doused his helmet lights. On his HUD the red and green dots were converging. Another few minutes and they would veer from the guide cable.

Eventually Gabe prompted, “Well?"

"Okay. I put my life in your hands.” Thad sighed. “I have a thing for Tiny."

Tina Lundgren was big for an astronaut, even a male astronaut. The nickname was inevitable—and you used it within her earshot at your own peril. Gabe had to admit that, in an Amazonian kind of way, she was sexy. And she was one of only two women, and the only unmarried woman, on Phoebe. Gabe understood Thad wanting this conversation on a private channel.

Having bared his soul, Thad went on and on about Tina's womanly charms.

"Uh-huh,” Gabe finally interrupted. “And you were cutting pipe as an outlet for your unrequited love?"

"Not exactly.” A rueful laugh. “I'm making a still. Whether or not homebrew appeals to her, I figure it won't go to waste."

"Does she know how you feel?” Gabe asked.

"Not from me! Not yet. Frankly, the woman scares the crap out of me. Maybe that's why I have to have her."

To their left, a ghostly plume: an ice pocket flashing to steam bursting from the ground.

Behind its sunshield Phoebe should be colder than the night side of the moon: For two weeks out of four, every part of the moon but a few deep polar craters felt sunlight. But shield or no, some sunlight
did
reach Phoebe. No software was perfect, and occasionally the sunshield—tugged by Earth, Moon, and Phoebe, pushed by the solar wind and by sunlight itself, balancing the many conflicting forces with its own feeble thrusters—drifted out of position. Whenever that happened, sunlight beat directly on the surface. Even when the shield balanced perfectly, the traces of sunlight penetrating the shield scattered in unpredictable ways. Earthlight and moonlight were, in the final analysis, echoes of sunlight. And heat leaked from the underground base and its nuclear power plant. All that energy mingled, meandered, and reradiated in unpredictable ways.

And so, seemingly at random, little geysers. The vapor was too diffuse to do any harm. Most times. If you were unlucky, a geyser could sweep you right off Phoebe.

"A still,” Gabe repeated, his thoughts divided between the plume, already trailing off, the topo map on his HUD, the landscape sliding by inches beneath his visor, and the conversation. Ethyl alcohol boils at a lower temperature than water, so alcohol fumes waft up a still coil before water vapor. You separated out the early condensate. But
up
comes of having gravity. “Will a still even work in Phoebe's grav—"

Too much happened at once, the sequence unclear:

—A sharp tug on Gabe's backpack.

—Thad saying, “Wrong answer."

—A power alarm.

—A second yank.

—Helmet lights and HUD going dark.

—A hard shove forward.

Gabe twisted around. Earthlight showed Thad a good twenty feet away, receding. Just staring. And bulging from the mesh pouch of Thad's tool belt: two battery packs.

Without power for his suit's heating elements, Gabe would freeze within minutes. Already the cold seeped into him, body and thoughts turning sluggish. He got his feet beneath him, even as he ripped lengths of tether from their reels. He leapt.

His right foot slipped on loose gravel and he sailed far to the side.

The shorter tether pulled him up short. Its yank started him spinning even as the tug started him back toward the surface. Too slowly. He took the maneuvering pistol from its holster—but it slipped from fingers already numb with cold. As he drifted down he managed to grip a rock outcropping.

All the while, maintaining his distance, Thad watched. Stared.

"Why?” Gabe screamed. Not that his radio worked without batteries. Not that his shout could cross the vacuum. “Why are you doing this?"

Maybe his murderer read Gabe's lips. Whatever the reason, Thad shrugged.

Gabe advanced. Thad retreated.

As cold became all, as consciousness faded, the last thing Gabe saw was the waxing crescent Earth.

Earth no longer seemed close enough to touch.

"He just went
nuts
!” Thad said once more.

With minor variations the words had become his mantra. First with Tiny, when he had called in from across Phoebe about the “accident.” Over and over with Bryce Lewis and Alan Childs after they joined Thad on the surface. And now hopefully for the last time, in the station's comm-gear-packed command center, with Lyman Hsu, the dour station chief.

"Details, please.” Hsu rubbed his pencil-thin mustache as he spoke.

Thad ignored the request. “You should have let me go with the other guys. You can't imagine what it was like.” I damn well hope you can't imagine it.
He
struggled to understand it.

"You'd been outside long enough for one day. You know the rules."

Because their utility craft were little more than flying broomsticks: compressed-air bottles, saddles, and minimal controls mounted to latticework frames. A counterpressure suit was your only protection.

"But I don't have to like the rules,” Thad said. Which, emphatically, he did not. What if he had overlooked something? Joining the rescue team might have given him a chance to cover his tracks.

"Details,” Hsu prompted.

"You heard Gabe switch to private channel two.” It had all come down to Gabe taking his cue, because everything on the public channel got recorded. Sooner or later, he would have figured out what Thad was building. Certainly the bullshit about Tiny and making a still for her would not bear scrutiny. That fable was all Thad could come up with on the spot, blather to occupy Gabe's mind until they got farther from the station. “When I linked in, Gabe was already mid-rant. He missed Jillian, unbearably. He knew—but couldn't explain how—that she was cheating on him. He loved her and needed her and couldn't bear for anyone else to be with her. He would show her. And then"—Thad paused dramatically—"he unclipped his tethers."

"And you . . . ?"

"What do you
think
, Lyman? I tried to talk sense into him, damn it."

"And not a word of this reported to base."

"I didn't dare switch channels! There was no telling what Gabe might do if I wasn't on. If I didn't respond when he expected an answer."

"And he jumped anyway."