A large anthology of sci.., p.1009
A Large Anthology of Science Fiction, page 1009
“I told her not to go so fast,” Ryan interjected.
Ignoring him, Kate continued. “And with the battery drained and solar cells busted, I have a lot of ground to cover before dark, which is approximately when I will freeze to death or suffocate.”
“NASA predicts the former.”
“As my crewmate has so courteously informed me, I will turn into a giant, Mylar-covered popsicle in about five hours. Right now, my only chance is to meet the rescue rover somewhere along the way, which is somewhat hard to do when I can barely stand. If you have any printing capabilities, I’d really appreciate a crutch or cane of some kind.”
“A little more information than he needs at the moment. Talk about pressure,” Ryan said.
Blake’s heart was racing. These past few years, he had grown accustomed to having nothing but time on his hands, time to wait, think, and plan, but now his action or inaction could decide someone’s fate. Ryan was right; the pressure was too much. His fingers shook so badly he didn’t think he could design anything. He was grateful he’d already sent the crutch schematics.
When he tested his voice, it shuddered. He took a moment to regain his composure.
“The crutch should be printing now. I designed it to meet your height and weight parameters. It’s pretty minimalist, so don’t expect anything pretty. If it doesn’t quite work, I can add or cut off some bits. I estimate it will take about thirty minutes.” He paused. “I’m sorry if rovers like me were responsible for your situation. Please, let me know if there is anything else I can do.”
Blake sent the message.
A dozen minutes later, the 3D printer arm began to move again. Its tungsten tip became white hot. The thin wire he had collected at midday unspooled and fed into the printer arm. It began to construct the crutch at its base, building the flat disk layer by layer. When it was large enough, the rover’s manipulator arm took hold of it for support.
Kate finished reattaching her backpack and limped over to look.
Again, his voice came through the speakers. He cringed at the sound of it.
“That was fast,” Ryan said.
“Thank you, Feldspar. I don’t blame you for any of this. I’ve always had a thing for speed.”
“And going further than you’re supposed to?”
“Come on, Ryan. I was almost to the mouth of Maja Vallas, kilometers away from Dromore crater. The potential for ice plugs is huge. The so-called ‘exploration zone’ is a joke.”
“Doesn’t feel like a joke now, does it?”
The speakers on either side of his display went quiet. When the crutch was finished, Kate pulled it free from the small rover’s grip. She tested her weight on it and walked in circles around Feldspar, making the occasional sound of approval.
Ryan broke the silence.
“Kate, be advised. NASA informs me that they’ve pulled the crutch design from Feldspar’s server. After extensive review and analysis, they concede that it will support your weight.”
Kate laughed. “Thanks NASA. Way to be late to the game. I’ve already tested it.”
“There’s something else. They say they’ve received permission from TerraForm Games to scrap Feldspar if needed. These rovers are equipped with some pretty impressive hardware. The battery and solar panels can get you a couple more hours of heat.”
“That’s pretty cold, NASA.”
“They’ve assured me they’ll purchase him a replacement rover. They can also convert the atmosphere into oxygen; there’s a port on its right side.”
Kate hobbled over and disappeared from view as she examined his small rover.
“Even if I could somehow form a perfect seal with that port, how will the rover power it after I’ve ripped the battery out of him?”
Silence held the line for a moment.
“They’re running the numbers.”
“I don’t really care what they say. I won’t strip down his rover. He’s been here for several years more than we have. The amount of scientific data pouring in from this game has been infinitely more valuable than anything we’ve collected so far.”
“Don’t give me that ‘for the sake of science’ crap.”
“Listen to yourself. This entire mission is for the sake of science.”
“You mean so much more than that,” Ryan said. The words spilled out of her crewmate in a rush. Blake could hear the desperation in the man’s voice.
“Ryan, I . . .” Her voice was softer now, sympathetic. “Can you move us to a private channel?”
Blake didn’t hesitate.
“Don’t worry about me. Do what you need to do.”
While the message was flying through space toward the red planet, Kate and Ryan continued their private conversation. With her golden visor in place, he could not see her expression, but her body language was clear. She was trying to tell Ryan to let her go, to give her up.
Blake slouched forward in his chair, thinking. He was not thrilled about someone scrapping Feldspar for parts; in fact, it was a recurring nightmare of his. But he would sacrifice anything to give Kate a chance.
Even as the thought echoed through his head, he realized there was something else he could sacrifice, something worth far more than a few hours of heat and air. It would give her more than just a chance.
A surge of hope straightened his back, and he scrambled at the touchpads. He tried to keep the smile from his voice.
“Also, if it’s any help, I have an insulated shelter about seven kilometers from here with two fully charged batteries and a tank of compressed oxygen.”
She went completely still when his message arrived and then shook her head slowly and gave a small shrug. A second later, Ryan’s voice came back on the channel.
“Hey kid, are you serious?”
“I think we have to assume he is,” Kate said. “What other choice is there?”
“You can scrap him.”
“Fine, I’ll scrap him if he’s lying,” Kate said in exasperation. “But if he’s telling the truth, I could have a place to stay while Svetlana and Dave come for me.”
Ryan sighed. “What are the coordinates?”
Blake read them aloud. He’d never given them to anyone before, and he couldn’t help but feel like all of his secrecy these past few years was for nothing. After today, everyone will have heard of Feldspar’s hidden home.
When the transmission arrived, Kate laughed. “That’s near Dromore crater.”
“I guess you’ll have a chance to see it after all.”
Rather than wait for NASA’s approval, Kate began to hobble in that direction on her new crutch.
Blake reinitiated his previous navigation protocol as Kate took the lead, creating tracks for him to follow. While the crutch helped her maintain a steady pace, he could tell by her winded conversation with Ryan that the seven kilometer distance pushed her to her limits. The deepening drifts of sand and the slight increase in elevation as they approached the crater’s rim tested her endurance even further. Rocks were strewn across the barren ground, their size and proximity causing Feldspar to pause and adjust navigation on several occasions.
During the last leg of the journey, Kate made a dismayed sound.
“CO2 scrubber is maxed out. My suit’s gonna start purging air to keep the CO2 levels below one percent. That’ll only last as long as I have oxygen and nitrogen to replace it, and I don’t have much.”
“We’ll see you through this, Kate,” Ryan said soberly, and then his voice became businesslike. “Feldspar, how much oxygen do you have, precisely? And what kind of fitting does the regulator have? NASA will send you more questions any minute now so check your inbox. They’ve also sent you the specs for the suit’s hose fittings. If it won’t fit your tank, you’ll need to print a suitable adaptor.”
Sure enough, the specs were already in his inbox with a fancy NASA header and the word “confidential” in large, red letters. Someone had made the adaptor with compatible design software, and the message asked him to add the female end for his tank. Blake promptly replied to the message, stating that he would just weld it onto the tank’s outlet to save time and ensure a better seal.
Dozens of other messages and inquiries about his shelter arrived immediately after his response. Blake did his best to address them all, but soon gave up and sent all of his detailed schematics. He felt a little violated at the thought of dozens of techs pouring over the designs he’d spent years perfecting.
Blake put NASA out of his mind long enough to respond to Ryan.
“I received it. I should have enough metal to make adaptors for both the oxygen and nitrogen tanks. Both are about forty liters large and average one thousand PSI.”
When Blake’s transmission went through, Ryan sputtered in disbelief.
“Nitrogen? I’ll buy that you somehow managed to print a tank and that you’ve pressurized it with oxygen, but nitrogen? What is the concentration in the atmosphere? Two percent? How could you possibly separate it from the other gasses?”
“Zeolite,” Blake said. “And a few other aluminosilicates. At high pressures, nitrogen sticks to the mixture. When the oxygen moves into the second tank, the pressure drops, and nitrogen is all that remains. I repeated the process hundreds of times. It should all be pressurized nitrogen. The regulator is something I’ve had to build myself, but I salvaged the compressor from another rover’s AIR module.”
“He’s right,” Kate said when his response arrived. “We have a similar system at Base Camp. Space stations and hospitals have been using zeolite for decades to concentrate oxygen and capture nitrogen. It’s called pressure swing absorption.”
“Where the hell’d he get zeolite?”
“I suspect he did his research before Project Regolith started. That’s why he named his rover Feldspar,” Kate said. Blake smiled. No one had ever puzzled out the origin of his rover’s name before. The last person he’d told had assumed it was named after some dwarven hero in a fantasy game.
“I’m confused.”
“Feldspar is a family of minerals called aluminosilicates,” she explained. “Project Regolith only had their sights on the iron in the dirt, so he found a use for the rest, the stuff they were just throwing away. They call it slag.”
Ryan made a sound that Blake could only describe as grudging agreement.
“I suppose you’re right. NASA just forwarded the schematics for the shelter. Get this; he’s filled all of the walls with slag. According to NASA, it’s as good an insulator as you’ll find on this planet. He even filled a pit with the stuff because it’s porous and effective at leaching water from the ground.”
“Are all Project Regolith rovers this resourceful?” She sounded breathless.
“Hardly. That friend I mentioned? He went by the name Lugnut and spent years printing a vintage car that has no chance of running.”
“It’s as if our rover operator intended to live here one day,” Kate said.
“You should really look at this thing, Kate. The schematics are like nothing I’ve ever come across.”
“I think I do see it . . .”
Beside Dromore crater was a wide but shallow canyon created by one of many ancient waterways that crisscrossed this region of Chryse Planitia, an area called Maha Vallas. A unique feature stood out among the others as they descended into the canyon. Imbedded in the wall of the ancient waterway was a flat, circular door. Years of exposure to the elements had tarnished its surface, but it still glimmered in the fading sunlight.
“Yeah, that’s definitely it.”
“I shut down the camera feed to conserve power. What are you seeing?” Ryan asked.
“It looks like an airlock. It’s set into the side of a rock face. Feldspar, did you dig through the rock somehow?”
Blake leaned closer to the microphone at the base of the display, but Ryan already had the answer.
“From his notes, NASA thinks it was an old lava tube that was exposed by erosion. It might even be an old water plug that slowly sublimated and formed a cavern. He’s reinforced the whole thing and sealed it off.”
“How do I get in?”
“Leave the entry to me,” Blake said.
They had moved to the very base of the door by the time the transmission went through. Kate dropped her crutch and sat down, leaning her back against the edge of the door.
Feldspar initiated the entry sequence. It rolled to a stop beside the large door and extended its manipulator arm. The pincers spread apart and inserted into a recess that was perfectly shaped to receive it. A small hole between the pincers led straight to the rover’s AIR module. The purpose of this feature was to air-dust the clingy sand from joints and solar panels. Instead, Feldspar sent the compressed oxygen into the door, where it fed into a piston near the hinges. The pressure drove the piston outward, easing the large door open.
Kate let out a low whistle and stood to peer through the widening gap. She limped around Feldspar and took a step inside.
“There’s a type of rubber surrounding the door. It’s a gasket, I think.”
“According to the schematics, they’re from the wheels of several salvaged rovers,” Ryan supplied.
“Will I lose coms if I enter?”
“Don’t think so. He’s had to operate in there too, remember. It looks like he’s placed an antenna from a rover out the top of the enclosure, on the edge of the chasm. There are salvaged solar panels up there too. That’s how he’s able to charge the batteries. Damn, this kid’s thought of everything.”
Feldspar’s automated sequence led him into the enclosure after Kate and then to another port. The rover repeated the previous sequence, but this time the pressurized air drove the piston in the opposite direction, closing the door.
Darkness engulfed them for an instant until Feldspar’s night navigation sequence activated, and a light on his camera module switched on. The space was only about as large as the room Blake sat in, except that all the corners were rounded and shone with a dull, metallic gleam.
There was a second, inner door to the airlock, which Feldspar usually left open, but they needed all the insulation they could get.
As Feldspar closed the second airlock door, Kate explored the small room. Her breathing was becoming strained, and her teeth were chattering. She succeeded in locating the narrow shelf holding the batteries. Several spliced wires, harvested from broken-down rovers, led from the batteries and up to disappear into the ceiling.
She removed her pack, dropped her crutch, and sat down beside the narrow shelf. She pried open the outer covering of the pack to expose tanks, wires, and hoses. Several minutes passed as she tried to pick up the battery leads and press them in to her own battery. The thick gloves and her undoubtedly numb fingers made progress slow.
“I can take control of Feldspar from here and operate him in real time. I can help you connect the battery leads. I’ve already patched into his camera, and the controls seem pretty straightforward.” The tension in Ryan’s voice suggested he was just as concerned as Blake.
“No, Ryan. The delay is annoying, I know, but he’s the only one who knows what he’s doing. Now, what’s the plan to get me more air? My nitrogen and oxygen are almost depleted.”
“Working on it,” Ryan said, even as Feldspar’s next sequence arrived, steering the rover around and toward the opposite end of the room.
Blake lined up one of the tank’s regulators in the display and pulled the hose adapter design from his software. He oriented it on the surface of the tank’s outlet and finalized it.
Kate sighed in relief.
“All right. My heaters are back online.”
The tungsten tip of Feldspar’s 3D printing arm grew white hot and cast a dim light on the wall. It eased closer to the tank’s outlet nozzle and began to deposit a thin layer of molten iron. It continued in a circular motion, leaving a line of glowing metal in its wake.
“Bad news. I’m out of gas. The CO2 will build up rapidly now that I can’t purge it.”
“So soon?” put in Ryan. “That can’t be right.”
“I was thinking the same. I suspect the crash damaged one of the tubes connecting my suit to the oxygen and nitrogen tanks. I must have lost a little every time the suit filled during a purge.”
“Feldspar, what’s the time estimate for those adaptors?”
“Twenty minutes tops for the oxygen tank adaptor. That is, it will take another twelve minutes once this message reaches you. It’s a higher precision print than the crutch because of all the fine detail.”
Every few minutes, Kate updated them on the CO2 percentage. It rose from 0.4 percent to 1.5 percent before his transmission went through. At each update, he felt as if the hand of a large, unseen clock was counting down to Kate’s death. The delay was not helping. What he was seeing and hearing was happening eight minutes ago, and he was powerless to step in and intervene.
“CO2 is three point one percent. Oxygen . . . ten percent,” she said. Her words were lethargic.
“All right Kate. I’m gonna need you to head over to Feldspar, he’s almost done with the adaptor,” Ryan said after a short pause.
Blake leaned back and sighed. If those words left Mars eight minutes ago, it was likely Kate had already connected her line and was breathing oxygen. He had done it. He had come across an astronaut in the middle of Chryse Planitia and helped her stay alive.
“Kate? Do you read?”
Blake sat up, but he couldn’t hear anything except for the faint sounds of breathing.
“Damn it. Stay awake, Kate,” Ryan said.
Silence greeted the command.
The video feed continued to show a view of the oxygen tank as Feldspar printed the last section of the adaptor. A moment later, a red light flashed beside his status display.
