Abruptly—the thought convulsed her muscles before fully taking form—Yarrow grabbed hard on the brake. The grip shrieked, slewing her forward as it slowed. She struck the rail with her opposite forearm, releasing the grip, and rebounded against its tethered length. Feeling the rail rasp against her ribs, she grabbed at it with both hands, a tailless monkey clutching the last strung vine.
Breathing hard, Yarrow looked down the rail stretching before her, which disappeared unbroken over the near horizon. The image was coming clear only now in her mind: the glideline, snapped by meteoric debris, seismic shifting, or perhaps just cold stress, raising two jagged ends pointing just past each other. A glider, oblivious in the darkness, flies off it like a load fired from a mass driver, sailing on a tangent into a Neptune orbit of its own.
Very slowly, Yarrow let go of the rail and, after floating free for several seconds, began to pull herself, hand over hand, along its length. She narrowed the focus of her beam and ran it carefully along the rail for a dozen meters ahead of her. In the absence of visual landmarks, the receding ribbon swelled in scale: a tram line soaring over a polar plain.
No breaks were apparent, but Yarrow found herself unable to glance to either side for more than a few seconds before she felt compelled to look back at the glideline. How fast could a worker escape the Teardrop and still be able to return via his jetpack? Was George perhaps returning now? (She scanned the sky.) Had the Teardrop’s spin placed him over its opposite hemisphere, from which he might return to the duster unseen by her? (But then would not the Voice recall her?)
Something was wrong with her reasoning, but she didn’t dare pause to find it. Enjoining herself to think clearly, she called up the duty sheet on her screen and wondered which tasks George would have turned to first. Presumably those that a single person could accomplish; the rest would be best deferred.
In the event, George seemed to have begun with the tasks closest to hand, pausing at each stop like a milkman. A water processor whose microwave dish had darkened with dust had been cleaned; and a large cutting device, its talons gripping square meters of ice that had begun to fracture under the strain, had been (crudely) repositioned. “Going to let me discover everything on my own?” she asked, expecting and getting no answer.
Something was wrong at the third site. A scaffold post, emerging slowly over the horizon, leaned at a vertiginous angle; and Yarrow soon saw a jig, slight but unmistakable, in the glideline’s path. Her heart in her mouth, she approached it cautiously; but the ribbon proved unbroken. The worksite beyond was now visible, however, and she saw what had happened at once.
A deep trench had been opened in the ice, a smooth-walled crevasse, several meters deep, that had permitted core samples to be taken from several degrees of arc. Once a meter wide, the trench had crunched shut like a frost giant’s crooked mouth. Splintered icecakes piled up at the ragged seam, and the ground seemed lower to one side.
Yarrow shifted her grip to the tributary gliderail and approached the site cautiously. The ribbon ran beside the trench site—a guardrail overlooking the verge of a vanished canyon—permitting her to shine her beam along the impacted edge. Two thirds of the way down she saw it: a glimpse of clensuit among the glittering shards.
“Jesus Christ,” she said. Christians had the best maledictions.
Grasping spurs of ice, Yarrow pulled herself closer. Wedging one boot in a crevasse, she began to prise away blocks of rubble. Quickly she discovered that the clensuit lay half a meter below ground level, glinting between two floes propped against each other. It took her nearly an hour to clear the intervening space: although gravity was negligible, loose chunks of ice kept spilling into her excavation from isostatic pressure.
The scrap was George’s shoulder, which meant that his helmet lay beneath a large block that was pinned by surrounding rubble. Yarrow hooked her fingers under the block, which proved too massive to dislodge. She thought she could feel a helmet collar.
She fumbled through her belt kit, which contained a small cutting laser. Even at sharpest focus, the device was barely sufficient for spot welding; but how much power did it require to vaporize ice?
Quite a bit, she soon discovered: the beam produced a small puff of steam but made remarkably little headway. Belatedly Yarrow remembered that that the ice on the Teardrop was only 50°K, and could absorb much heat before melting. In the end she sharpened its focus to a pinpoint and sought to slice through the floe. When this failed to work—the escaping steam, she suspected, was refreezing in the space she had already cut—she took out her pick and hacked angrily. The nanometer-scale tip pierced the ice readily, and after some effort Yarrow broke the block in two and wedged the halves centimeters apart.
George’s helmet was dusted with ice, but did not possess the frosted rime of escaped air. Leaning in as close as she could, Yarrow touched the tip of her laser to his helmet, then pressed its handle against her own.
“George, can you hear me? I’m trying to dig you out. You don’t need your radio to respond.”
No sound, not even the ragged susurrus of injured breathing. Yarrow thought of something.
“I don’t know your relationship with the Voice from the Centaur, but it can’t hear you from here. Didn’t even know what happened to you. It untied me so I could haul you back, but if there’s anything you have to say that you don’t want it to hear, now’s the time.”
No response. Yarrow wondered if George was being cagy, or just dead. It wasn’t easy to breach the integrity of a clensuit, but tectonic forces, even those of a comet, might suffice.
She climbed out of the hole she had dug, found a piece of wallboard, and sliced it into long rectangles. Returning to her hole (which was slowly filling) she resumed digging, using the boards as crude bulwarks. She didn’t check her watch; but by the time she had finished she had drained her suit’s store of fruit juice and was feeling aching tremors in her arms and back. George’s upper body lay exposed at the bottom of a three-sided well; Yarrow had shucked her jetpack and most of her hand tools in order to reach past him in the narrow confines. She touched her forefinger to the display stud on George’s chest and read the numbers on her helmet display.
George’s body temperature was 31°C. The hypothermia of shock, or the clensuit warming a cooling corpse?
Yarrow had, in fact, little doubt. George’s chest seemed misshapen, and one shoulder plainly dislocated. She looped a cord under his arms, clambered to the top of her makeshift caisson, and slowly hauled him out.
Returning to the glideline, Yarrow felt his deadweight bouncing at the end of the cord, a helium balloon she did not glance back at. She secured the cord to the grip, grabbed its strap, and shoved herself briskly along the rail.
Belatedly she thought to activate her recorder, which would be examined at mission’s end. “Seventeen forty-three,” she said, “returning with body of George Chow, who was crushed when the fissure at Site Sixteen closed up. Possibly the shock of our landing stressed the ice; how long does it take for such pressure to work through supercold cometary material?”
Yarrow started to erase the last words, then remembered that mission tapes could not be altered. She tried to speak more carefully.
“The control exerted over my suit by the Voice that addressed me in the cabin does not seem to extend far beyond the ship. I do not understand its mechanism, and shall not speculate. Since it did not know what had befallen George, I imagine—”
Something grabbed her from behind. Yarrow shrieked, releasing the grip as a second arm snaked around her helmet, blocking her view.
Yarrow snatched at the arms, unthinkingly moving to break their grip on her throat. But the hands were scrabbling down her suit chest as though seeking to paw her breasts. She grabbed a wrist as its hand closed on her display stud and pulled it away.