by Ben Bova
Nathan Brice’s face appeared on the central screen, looking more composed than he had earlier.
“Good morning, Fermi,” he said, trying to smile and almost making it. “I hope you had a good night’s rest.”
Connover winced inwardly.
Without waiting for a response that would take most of an hour to reach him, Brice continued, “You’ve got some work to do before we can figure out exactly how we can fix your power problem. The telemetry from the reactor doesn’t look good. Something happened yesterday to the coolant flow, the reactor started to run hot and the automatic feedback loop powered the system down to seventy percent of normal, which it calculated would keep the heat levels to something the cooling system could handle. That’s when you had the brownout.”
McPherson muttered, “Tell us something we don’t already know.”
The flight director held up a schematic of the reactor and its cooling system.
“The coolant is liquid metal, sodium-potassium. It’s a standard reactor coolant and very safe to use. Unless, of course, you expose it to air or water, then it catches fire or explodes. But there’s very little air or water where you are.”
“Especially water,” Amanda grumbled.
“We think the problem is in the pumping system, but it might also be a problem with the radiators. The engineers here think the radiators are okay: the telemetry from them looks good.”
Pointing to the cooling system’s pump, he went on, “The pump keeps the coolant moving through the reactor and out to the radiators, where it gets rid of the heat. Very standard layout. The coolant doesn’t pick up much radioactivity: it doesn’t go inside the reactor, it just flows around it. That’s the good news.”
Connover nodded, waiting for the other shoe to drop.
“But somebody’s going to have to go out there and provide us with some visuals on the physical integrity of the system. Whoever it is will get a small dose of radiation; that can’t be helped. The medical people tell us that the dose should be minimal, no worries.”
“Great. Just great,” McPherson muttered.
Brice continued, “From the telemetry it looks like the pump is malfunctioning. We think one of its blades might have cracked. If that’s the case the system’s performance will continue to erode until the blade fails entirely and the reactor automatically shuts down.”
Dropping the schematic, Brice told them, “Now, the system is modular, and it’s designed to be repairable. That means you can get the pump and bring it inside your habitat to check it out. But before you do that you’re going to have to power down the reactor, and that will cut off the electricity it supplies to your habitat.”
Ted’s mind raced. We’ll have to do this in daylight. Clean off the solar panels before we shut down the reactor so we’ll have electricity to get through the day. Take out the pump, check it out and repair the bad blade. Get it all done before the sun goes down again.
Brice was going on, “We’ve uploaded the full schematics for the pump and the CAD files you’ll need to make spare parts with your 3D printer.” He took a breath. “We had planned to send backup parts for the nuke system on the follow-on flight. We didn’t expect a failure so early in the reactor’s life cycle. Bad decision on our part.”
“Yeah,” Ted whispered.
“The time delay between us,” Brice resumed, “means we won’t be able to coach you through this in real time. But we’ll definitely watch on the monitors and answer whatever questions you have as fast as the speed of light allows.”
With that, Brice looked around at the people surrounding him and finished with, “Good luck, guys.”
Connover hit the transmit button and said tersely. “Message received. Thanks. We’ll do our best.”
He clicked off the communicator and got up from his chair, stiffly, as if he’d aged ten years overnight.
As he looked at the faces of his three comrades, he said to himself, All right, you’re supposed to be the leader around here. So start leading.
“All three of you start prebreathing, right now. Hi, you and Amanda read and memorize how to remove that pump and get it in here so we can repair it. Catherine, you’ll have to clean off the solar panels and the tops of the gardens. And the radiator panels, too. I’ll download the CAD files they’ve sent and start the 3D printer going.”
“But we don’t know if the pump blade is really the problem,” Amanda objected.
“Yeah, but we don’t have time to do things in sequence. We’ve got to do ’em in parallel, without wasting a minute. We can’t afford to have the reactor totally shut down when the Sun goes down.”
“How much time will we have without the reactor?” McPherson asked.
“If we can get the solar panels operating at full capacity, we should be good during the daylight hours. The batteries will give us another six hours, maximum.”
“Not enough to get through another night,” said Catherine.
“That’s why we’ve got to get moving. Now!”
December 19, 2035
Mars Landing Plus 44 Days
10:21 Hours Universal Time
Elysium Planitia
In their excursion suits and helmets, Hiram and Amanda approached the nuclear reactor module. It stood twelve feet tall on the red Martian sands, looking like any other aerospace “cylinder,” except that it rested on three sturdy legs and had massive black panels protruding from its top—the radiators that got rid of the heat the reactor produced.
“Radiation levels increasing,” Amanda said, her eyes on the scintillation meter strapped to the wrist of her suit. “Just a tad over Mars background, but it’s getting higher as we get closer to the reactor.”
“That’s to be expected,” McPherson said.
“Nothing to worry about.”
“Why do people keep saying that?”
They trudged to the big cylinder, then stepped around it to find the hatch that covered its pump.
“Let’s do this right the first time,” McPherson said. “Quick and smart.”
Amanda nodded. “No unnecessary exposure to radiation.”
“Exactly.”
They checked the heads-up displays in their helmets, then McPherson took the power screwdriver from his belt and started unbolting the panel.
“Ted’s purged the pump with nitrogen,” Amanda said as she watched him working, swiftly, methodically, “so there won’t be any NaK leaking from it when we take it out.”
“Good thing,” said McPherson as he lifted the panel off and let it drop languidly to the ground. “Don’t want any NaK droplets on my suit when we go back into real air.”
“Spontaneously bursting into flames could ruin your whole day.”
“Right you are. Let’s get this puppy out of here.”
As they undid the connectors holding the pump in place, Amanda thought she could almost feel the nuclear radiation penetrating her suit and attacking her body. Like Marie Curie, she remembered. She and her husband discovered radium and characterized the properties of the radiation it emitted—and she got a lethal dose over the years and died slowly of radiation poisoning.
McPherson’s voice snapped her attention back to the here and now. “Amanda, did Mission Control say anything about how they’re keeping the reactor core from melting down without the coolant flowing?”
“The moderator rods slide into the core automatically when the reactor’s shut down. They absorb the neutrons that cause the chain reactions. No neutrons banging around, no fission reactions, no heat.”
“And Ted’s checked to see that the rods are in place?”
“Sure. You can ask him if you’re worried.”
“I was just curious, that’s all.”
But he felt relieved.
Even in Mars’ relatively low gravity the pump was almost too heavy for McPherson to remove. He quickly realized that it would take the two of them to carry it back to the habitat and that it would be slow going.
Like Jack and Jill carrying t
heir pail of water, Hi and Amanda toted the pump back to the habitat’s airlock.
“I wonder if my children are going to have two heads,” he half-joked.
“Or leukemia,” Amanda said.
“You’re a lot of fun!”
“They can cure leukemia.”
“And a kid with two heads can make a good living in the circus,” McPherson quipped, half-heartedly.
It was a few minutes past noon by the time they reached the airlock. McPherson noticed that the solar panels and the gardens looked clean.
Then he thought, We’ll have to clean off the reactor’s radiators, too; or maybe the wind will do that for us.
Connover was waiting for them inside the airlock. He took over for Amanda and, together with Hi, toted the ungainly looking pump to the workbench in the habitat’s right wing. It was noticeably colder in there; Ted was wearing a heavy pullover sweatshirt.
They placed the pump upright on the workbench. McPherson straightened up and flexed his arms to ease the cramp in his back, then unlatched his suit helmet and pulled it off his head.
The workbench was covered with tools, he saw, and Ted was slipping a pair of protective goggles over his eyes.
“Worried about some residual NaK being inside there?” he asked.
“Not worried. Cautious,” Ted replied. “Just in case the purge didn’t clean it out entirely. The last thing we need is for a—”
A flash of light made McPherson stagger backwards. Smoke poured from the pump and Ted crashed to the floor, curled up in a fetal ball, wringing his hands.
“Dammit! Dammit!” he moaned.
December 19, 2035
Mars Landing Plus 44 Days
12:36 Universal Time
Fermi Habitat
Stunned, McPherson gaped at Ted writhing on the floor. His face and right hand looked charred, black. Hi was glad Ted had worn the safety goggles.
Abruptly, Hi stirred into action, calling loudly, “Somebody grab a first-aid kit and tend to Ted while I make sure we don’t catch fire!”
Smoke was still pouring from the pump, resting upright on the workbench. McPherson yanked the fire extinguisher off the wall. A fire in the confined space of the habitat was the worst nightmare he could imagine. He had to make certain that the NaK hadn’t ignited anything else when it reacted with the air.
As he doused the pump and workbench with fire retardant, he saw that nothing else appeared to be burning and the smoke was thinning. He hoped there was no more NaK clinging to the pump’s innards.
Amanda and Catherine burst in and knelt beside Ted, spraying anti-burn lotion over his face and right hand. Tenderly, they slipped off his goggles and began to place burn treatment gauze on his face, covering his eyes even though they’d been protected from the flash burn by his goggles.
Amanda said something to Catherine that McPherson couldn’t hear, then got up and ducked out of the hatch. Hi saw that there was no fire, and the smoke had dissipated. Amanda came back in, tapping on her tablet. Looking up how to treat flash burns, Hi thought.
“Catherine, help me move Ted out to his hammock,” he said, reaching under Connover’s shoulders to gently raise him to a sitting position.
“I can walk,” Ted said, weakly. “I think.”
With Amanda behind them, tapping away on the notebook, Catherine and Hi half-dragged Ted into the central compartment. McPherson held Ted upright while Catherine unpinned his hammock and hung it in place. Then, together they stretched Connover onto it.
“Hurts,” Connover muttered. “Hurts like hell.”
“We’ll take care of you, buddy,” said McPherson. Looking up to the women, he said, “Amanda, you tend to Ted. Get some painkillers into him. Catherine, you know more about schematics than I do. Let’s get back to that pump and see how badly damaged it is.”
Catherine followed Hi back to the right wing and the damaged pump, still standing on the workbench, but looking charred and blackened.
Catherine slid her arms around McPherson and hugged him.
“That’s for luck,” she said. “We’re going to need it.”
She saw Ted’s notebook computer open on the workbench and peered at it briefly, then slipped on the same goggles Connover had been wearing. “There must be another pair of goggles in one of these drawers,” she said to McPherson.
The pump’s probably totally ruined, he thought, but he didn’t say it to Catherine. Not yet. Maybe there’s still a chance we can fix it. But he thought that chance must be very slim.
He stood beside Catherine, feeling pretty useless as she poked around inside the pump, glancing at the schematic on Ted’s notebook every few seconds.
“You ought to be wearing gloves,” he said.
Instead, Catherine lifted her goggles off her head. “If there was any more NaK inside, it would have flashed by now,” she said.
Feeling helpless, superfluous, McPherson said, “I’m going to see how Ted’s doing. I’ll be right back.”
She nodded, her attention totally focused on the pump.
McPherson ducked back into the central compartment and saw that Ted was passed out in his hammock, face and right hand bandaged.
Amanda looked up as he approached. “I’ve given him the painkillers the medical files called for and sent a message back to Houston, along with pictures of his burns.”
“Good work,” McPherson said.
“Now we have to wait for their reply.”
“Yeah.” Feeling equally useless at Ted’s side, he said, “I’m going back to help Catherine.”
“Sure. There’s not much else either one of can do here, for now.”
Catherine smiled tentatively as he re-entered the workroom. “It’s not as bad as I feared,” she said.
“Good.”
“The flash fire didn’t do much more than blacken the components inside the pump. Remember, this thing is designed to operate at over one thousand degrees Fahrenheit. A little poof of a flash fire cannot hurt it.”
McPherson said, “Great. Wonderful.”
“That’s the good news,” said Catherine. “Now for the bad. We’re going to have to remove all the soot inside the pump. It would contaminate the coolant and cause problems.”
“Okay,” he said. “We can do that.”
“And now the worst news. One of the pump blades is badly cracked. I’m surprised it hasn’t broken into two pieces.”
“Can we fix it? Ted had started the 3D printer on making a replacement blade, hadn’t he?”
“I’ve checked the CAD files that Houston sent up. There’s nothing for a replacement blade.”
“But . . .” McPherson sagged onto the bench. “But that’s the part we need!”
With a Gallic shrug, Catherine said, “We will have to wait for Houston’s call.”
McPherson was calculating how long it was until sunset. Once the solar panels shut down, they had only six hours of battery power. Not enough to get through the night. And it would be down to a hundred below zero before the Sun rose again.
December 19, 2035
Mars Landing Plus 44 Days
18:32 Universal Time
Fermi Habitat
Catherine and Hi stepped into the central module, where Connover was lying unconscious in his hammock. Amanda was at the desk, bent over her tablet.
She turned as they entered, and got to her feet.
“How’s he doing?” McPherson asked.
“Resting quietly, thanks to the painkillers. His eyes are okay, the goggles protected them. But he’s got some pretty bad burns on his face and right hand. I’m waiting for the medics back home to tell me what I should be doing.”
Waiting, thought McPherson. That’s all we can do: wait. While the Sun gets closer to the horizon.
It took an hour and five minutes to get meaningful information about the pump from Houston. And another forty-five minutes before the medical team sent advice about Connover’s immediate treatment.
The latter was better news than the fo
rmer.
The image of Ted’s personal physician, Pat Church, filled the screen. Normally Church looked cool and confident, but now his lean face was clearly tense, strained.
“Ted’s burns are going to be painful,” he said, utterly professional, “but they don’t look as if there’s going to be any serious risk of infection. From what we can tell, the burns on his face are second degree. The one on his right hand might be a third-degree burn and that’s the one you’ll have to watch. You’re doing the right thing by covering it with gauze and giving him painkillers. Let him rest and hopefully you’ll be able to uncover his eyes by tomorrow. I wouldn’t let him do much of anything for the next several days. We’ll reassess his need for painkillers then.”
The camera panned to Nathan Brice and another man, with the dark complexion and big liquid eyes of a Hindu, in a white open-necked shirt.
“I am sorry to tell you that I have bad news about the pump,” he began, in a lilting, rhythmic accent. “Dr. Clermont is correct, unfortunately. The problem is clearly with the cracked blade, and sadly your 3D printer cannot make a replacement blade that could survive the harsh environment within the pump.”
McPherson felt his insides go hollow. He glanced at Catherine, who seemed to be holding herself together. Amanda looked . . . angry, almost.
The engineer went on without hesitation. “Those blades are made in a complex process that cannot be duplicated in a 3D printer. There is no way to do it. It is not like making a hammer or a wrench or even a circuit board. Any blade you make with the 3D printer would fly apart once the pump began operating again.”
None of them said a word.
Brice took over again. “Guys, we’ve got our best engineers on this and I’m sure we’ll come up with something, but time is our enemy. You’ve only got, by our best estimate, another hour before the Sun sets, and then six hours of battery power. It’s going to get pretty rough out there. I suggest you get into your excursion suits. That’ll give you a few more hours. We’ll be in touch.”
The screen went blank.
Hiram, Catherine and Amanda stared at the screen for at least fifteen seconds after the image of Brice and the Indian engineer vanished.
