Saturn Run

15.

Sandy had spent a week working on the vid for the first test of the Nixon’s power plant. In fact, he’d worked right through New Year’s Eve, three days earlier. Fiorella, as it turned out, was a genius at explaining complicated technical matters in terms that anyone could understand, and occasionally even laugh at.

As with Becca Johansson’s solution for dissipating waste heat from the reactors…

Sandy launched his egg from the central axle and took it a kilometer out. In the past year, the metamorphosis of USSS3 station into the Richard M. Nixon had come a long way. He’d documented all of the major construction activities, the vid instantly relayed groundside. If anything went wrong, if there were any problems, analysis of the vid might give clues for possible fixes.

The Nixon was obviously a reworked USSS3. It still had three parallel tubes, side by side and spaced a hundred meters apart. The two outer tubes, each a hundred meters long, still contained the ship’s living quarters and were still known as Habitats 1 and 2. The center tube, the axle, contained storage and the shuttle bay.

The axle, instead of stopping where it intersected the rear connecting elevator tubes, continued back for another two hundred and seventy meters. About halfway back on the extended axle—all of it still zero-gee—were the engineering section and the twin reactors of the nuclear power plant. At the aft end, another hundred meters away from the reactors, the VASIMRs were still under construction. Between the reactors and the engineering system were a cluster of spherical tanks that would hold the thousands of tons of water that would make up the reaction mass for the VASIMRs.

And then there was Becca’s answer to the waste heat problem. In the nine weeks since the Chinese had launched, she’d moved heaven, Earth, and no small number of recalcitrant engineers. Between Engineering and the reactor modules, two four-hundred-meter-long masts projected out from the center axle, from Sandy’s viewpoint, one “up,” one “down.” At the end of each mast was what Sandy, who had done some sailing, thought of as a spar—but which also looked like the crossbar on a capital letter T.

Two more beams, the same length as the top spars on the T, projected out “horizontally” for a hundred meters on both sides of the axle. They held the extrusion nozzles for the molten radiator alloy that Becca Johansson would use to cool the reactors. The “T” spars would re-collect the now-frozen alloy, effectively thin sheets of foil, and send it back to the reactor.

Dozens of nearly invisible guy wires ran from the booms and masts to the axle. The guy wires were made of graphene composites that tied all the pieces into a rigid structure, far more inflexible and lightweight than any equivalent scaffold of metal. It reminded Sandy of an unfinished box kite, all balsa wood struts and string. At this moment, the struts were bare.

Shortly, there would be sails.

The engineers and design teams had fallen in line behind Becca Johansson’s scheme for handling the Nixon’s prodigious power demands. Not because they were happy with it; they just couldn’t think of anything else that would let them beat the Chinese to Saturn.

Grumbling, they designed a ceramic core reactor that ran at a glowing-yellow temperature and heated the primary coolant—pressurized liquid sodium—to over nineteen hundred degrees Celsius. The superheated liquid sodium ran through a heat exchanger where it boiled more sodium. That vapor drove the primary ceramic composite turbines at two hundred atmospheres and nineteen hundred degrees Celsius.

The sodium vapor condensed downstream of the turbine, in a secondary heat exchanger, where it heated steam to a supercritical eight hundred and eighty degrees. That drove the next set of turbines. Extreme as all of this was, it didn’t justify an epithet like harebrained.

The final stage was another matter.

Downstream of the secondary turbines, the steam, cooled to six hundred and fifty degrees Celsius, entered the heat exchanger for the ship’s radiators. It melted radiator alloy, a eutectic blend of aluminum, magnesium, and beryllium that liquefied at six hundred degrees Celsius. In doing so, it absorbed nearly two hundred watt-hours of heat per kilogram of melt. All Becca had to do was get rid of the heat in the molten alloy, and that was what merited the epithet.

Her heat exchanger extruded the alloy into space in molten ribbons a meter wide and a tenth of a millimeter thick. Cold rollers in the extrusion nozzles clad the ribbons in a skin of frozen and roughened alloy, just microns thick.

The rough skin improved the ribbons’ heat radiation properties and kept the thin, wide bands of liquid alloy from breaking apart into a spray of droplets. As they sped toward the spars four hundred meters away, the ribbons cooled and froze, radiating tremendous amounts of energy into space.

It was a brutally efficient scheme for dumping the vast amounts of heat, but it was tricky.

The nearly liquid ribbons of metal had to be guided electromagnetically as they squirted out from both sides of an extrusion boom, and then led to the spars over four hundred meters out. There, the solidified ribbon was fed by rollers mounted on the spars to the central masts and back down into the melting pot. Managing one ribbon was a technically challenging feat. For Becca’s system to get the Nixon to Saturn, it had to extrude and control hundreds of them, all at the same time.

Thus, sails—or, for the more poetic, a moth with huge wings and a tiny body.

Each of the sails comprised almost a hundred ribbons, running side by side from the boom that extruded them to the spars, across the spars and back to the heat exchanger reservoir. The alloy circulated perpetually, hundreds of semi-molten ribbons in constant motion, safely disposing of the reactors’ waste heat. When the ship was under full power, 150,000 square meters of the dull silvery metal—the equivalent of twenty-eight American football fields—would radiate nine gigawatts of heat into space. So said the theory.

As for the practice, the first full-scale test would give them a good idea of what worked, and what might not.

The power engineers had to bring the reactors online to produce enough heat and power to test out the turbines and the boilers and melt the alloy reservoir of the heat exchanger. But they couldn’t go too far, too quickly, because the relatively puny auxiliary cooling system had to handle the thermal load until the main heat exchanger was fully operational. It was a delicate matter. Reactors of this design didn’t really like being run at less than one percent of their rated output. If an instability got out of hand it could result in a core meltdown, and that would be the end of the mission, and possibly the space station.

From a cinematographer’s point of view, the first days were mind-blowingly boring. When you’ve photographed one status display being monitored by a furrow-browed engineer, you’ve photographed them all.

But after a week, life got interesting again. The reactors were as happy as they were ever going to be; the heat exchanger reservoir was stable at its operating temperature of just over six hundred degrees Celsius; and all the guidance sensors were nominal. Becca had taken a deep breath and given the instruction to open one slot nozzle, at minimum operating pressure.

Slowly, slowly a tenth-millimeter-thick, meter-wide ribbon of metal crawled out of the boom toward one of the spars. It wavered for a moment, wobbled, and then the guidance sensors and control magnets latched onto it. Dedicated supercomputers analyzed the ribbon’s hesitant path and issued instructions to guidance magnets to induce precisely formulated eddy currents into the ribbon. Electromagnetism did its part; the ribbon was forced back onto the straight and narrow toward the waiting spar.

After two minutes, the leading end of the ribbon reached the recovery spar, was picked up by the rollers, and fed across the spar and back down the mast.

Engineering broke out in cheers. Sandy was happy; it was dramatic. That languorous silver band creeping across four hundred meters of space was great for building tension, and Sandy planned to include every second of that footage in the final cut. Make the audience sweat the same way the engineers had.

The engineers opened the second nozzle and extruded a second meter-wide ribbon. It behaved much like the first. There were three hundred and fifty more of these to go. Allowing for pauses for status checks, the engineers would be at it for eighteen hours before all four sails were fully deployed. Sandy stuck a camera on a station-keeping pod to record the repetitive affair in real-time mode, and left for the day.

Back in the ship, he headed into a ladies’ restroom, where he found Martinez gluing a toilet-paper holder in one of the booths, while Fiorella, standing outside, was getting her hair done. She said, “You’re late.”

“But not too late,” Sandy said. “I was here earlier, I worked out the lighting.”

The Reds he was using didn’t need much light, but Sandy needed shadows—the light in the restroom was simply too flat and indirect to be interesting. He rolled his equipment case into the restroom and began sticking LED-light panels to the walls.

When they were ready, Fiorella sat on the toilet seat. On either side of her, at chest height, were two toilet paper rollers, one with a roll of toilet paper on it, the other bare; Martinez had installed the second one, and moved the first one to the right height for the shot.

They were about to start shooting when Fang-Castro stuck her head in the door and said, “I really didn’t want to know about things like this, but then somebody had to tell me. Why did they do that? Why do people tell me about things like this?”

She shook her head and disappeared again.

“Heckled from the cheap seats,” Martinez said.

Sandy had stuck his Reds to the restroom walls, controlling them from his slate, and said, “We’re on.”

Fiorella said to the cameras, “The problem was getting rid of the heat. The only feasible way to do that was to extrude extremely thin bands of molten metal into space, where, after they froze—thus getting rid of all the heat—they’d be gathered up and recycled into the ship’s reactor, where they’d be remelted….

“Think of it as working like this toilet paper roll.” She took a tab of toilet paper between her fingers and began pulling it across in front of her, toward the bare roller. “The molten metal is extruded into space, in a ribbon, like this paper. It then crosses to the other side, where it is picked up by a roller.”

Martinez had put a thin line of adhesive on the top of the roller, and Fiorella carefully stuck the paper to it, then began turning the empty roller, taking up the toilet paper.

They did it seven times before they had enough fragments of good vid that the editors could make it into one continuous segment; and it ended with Martinez on his back, under the toilet and between Fiorella’s legs, providing invisible drag on the feed roller with his fingers, while Sandy focused on bringing up the gold flecks in Fiorella’s eyes.

When they were done, and Fiorella and Martinez were back on their feet, Martinez said, “That was really pretty easy, except when the toilet paper broke.”

“That’s why we have editors,” Sandy said. “The paper won’t break on screen.”

The next morning, back in his egg, Sandy watched as four giant frosted-pewter rectangles of metal, hundreds of meters in size, ran from the spars to the booms, like square-rigged sails. The alignment was so perfect that from a distance the sails looked like single sheets instead of hundreds of parallel ribbons of radiator alloy.

He recovered his automated camera and moved it, reset it, changed memory modules: the cameras had both internal memory and simultaneous remote recording capability that went straight into a dedicated memory core in the station. Some videographers thought the equipment was now so good that no backup was really needed. Sandy had never believed that: he backed up everything.

He was outside that morning because Becca Johansson and the other engineers were finding out if their baby could walk. The reactor managers would take their plants up to twenty-five percent of rated output, the first field test of the reactors under anything close to normal operating conditions. For the time being, they’d be bypassing the turbine-generator stage. Dumping all the power into the heat exchanger would test its capabilities to over fifty percent of full capacity.

Ramping up the heat exchanger-radiator system was simple enough in concept; it just required speeding up the extruders. The faster the metal got fed into space, the faster they could dump waste heat. Currently the extruders were streaming ribbons at a leisurely three meters per second, but in full operation the ribbon velocity would be over a hundred and sixty meters per second. The plan for the day would be to take the ribbons to ninety meters per second. If that worked, the system would be taken down while Sandy and the other engineers went over every bit of data produced by the dozens of recorders watching the event.

Even at the slower ninety meters per second, everything needed to work hand in hand perfectly. The heat exchanger needed sufficient heat coming in from the reactors to keep the alloy reservoir molten. If the extruders ran too fast for the reactors, the exchanger would dump too much heat into space and the reservoir would cool down. If the temperature dropped below the six-hundred-degree melting point of the radiator alloy, the reservoir would freeze up and the engineers would have to shut it down. So the reactors depended upon the heat exchanger to keep from melting down, and the heat exchanger depended upon the reactors to keep from freezing up.

Sandy, waiting for the test to begin, focused on giving Fiorella as many different views of the station as he could, using a variety of imaging techniques. He would switch from normal real-color imaging to thermal imaging, and the sails would go to a brilliant white, set in a framework of dim, dark gray masts and booms and other station components, with a dull gray Earth in the background. When he had enough of that, he thumbed through a variety of alternative modes, doing false-color mapping, which showed sail temperatures in a rainbow of hues. Fodder for the editing session later; anything to jazz up the presentation.

When the test began, it looked like nothing. Nothing changed.

Sandy slowly panned back and forth over the station, muttering notes to himself into his throat mike, the Red dutifully capturing all that as well as multiple channels of audio from Engineering.

In fifteen minutes, he had more vid than Fiorella would ever be able to use, so he picked the best spot, a kilometer out, set two cameras at different focal lengths, picked up his slate, and went back to a novel he’d been reading.

In an hour, the reactors were up to five percent, dumping nearly a gigawatt of heat into the exchanger and radiators. Ribbons streamed out at twenty meters a second. The reactor managers sounded happy. The heat exchanger engineers sounded happy. Dr. Johansson sounded slightly less stressed than usual. Sandy went back to his novel, a bit of undemanding popular science-fictional fluff about the first space mission to Jupiter. Set ten years in the future, he thought. How quaint: this mission would blow Jupiter’s doors off.

Each time he scrolled the tab’s screen, Sandy glanced up at the sails. The Reds would run fine on their own, unattended, he was just spot-checking. As the station moved in its orbit about the earth, the sun’s light constantly changed angles and intensity. There was the especially dramatic transition from lightside to darkside and vice versa on the earth. Sure, it was repeated every two hours, but audiences lapped it up. More eye candy he could edit into the footage so that viewers wouldn’t notice that nothing interesting was happening. Occasionally he panned across the earth to capture the sunset/sunrise terminator and its delicate rainbow, or the lights from humanity’s bigger and brighter megaplexes.

Two and a half hours into the test, Fiorella and Martinez came out in separate eggs, Fiorella’s egg slaved to Martinez’s. Sandy spent an hour doing close-up shots of Fiorella in her egg, commenting on the sails in the background. Martinez hovered behind Sandy, out of camera range.

When they were satisfied with the vid, Martinez and Fiorella looped over to the far side of the test ribbons, so that Sandy could shoot them with the ribbons in the foreground, the earth in the background.

The reactors were up to twenty percent. The heat exchanger was happily dissipating 3.5 gigawatts, its ribbons zipping along at seventy meters per second. Out of the corner of his eye, Sandy caught a glimmer of light off one of the sails. Something different.

He said, “I’m seeing something different out there, what’s… Hey! You guys! Joe! Cassie! Back up! Back up! Get out of there, get away!”

He started to zoom in on that section of that sail with Camera 1, his longest lens, when he saw more glimmers, then ripples of light starting to flicker across the sail. He zoomed Camera 2, catching the ripples, but carefully kept Fiorella’s and Martinez’s eggs in the shot, then thumbed over to object-lock, locking Fiorella’s egg onto Camera 2. It would track her wherever she went, within the limitations of his egg’s attitude and the Red’s gimbals. Martinez was backing them off, as the ripples and flickers extended over all four sails.

A second later, the sails exploded.

That’s what it looked like, anyway, from Sandy’s vantage point.

The three hundred and fifty-two silvery metal ribbons making up the sails broke free of their lock-step, straight-as-arrow paths and went flying wildly into space, thin silver streamers spewing out in all directions like Christmas tinsel.

He’d dealt with any number of explosions in the Tri-Border area, and one of the things that he had learned was that if the explosion didn’t kill you outright, you could get killed by the stuff coming down. Like bricks. He’d trained himself to look up after something blew: a flying brick was like a softball lofted into the outfield, and you could easily dodge it, if you could see it. Your mind would automatically scope out the vectors of the various flying pieces of rubble.

As the cloud of silvery threads grew, Sandy saw a hole forming in the expanding ball of chaff, and his explosion-trained brain told him the various object vectors wouldn’t be passing through the hole. He jammed the egg into it, careful to keep the egg oriented toward Fiorella’s and Martinez’s eggs, so Camera 2 could track them. He put Camera 1, with the half-million-dollar lens, on the corner of the extruder where the ripples had started and thumbed the constant focus setting, and closed in on it, at the same time selecting both real-color and thermal settings, and the highest recording speed.

As he dove in on the extruders, Martinez started screaming at him: “Get out of there, you crazy motherfucker. Go north, go north. Get out…”

Fang-Castro’s cool voice interrupted: “Mr. Darlington, do what you think best. Those vids will be valuable. Mr. Martinez, try not to distract Mr. Darlington any more than is necessary to warn him of a problem he may not be able to see.”

Then another woman’s voice, as cool as Fang-Castro’s: “This is Johansson. Darlington, we’re monitoring your vid. We could use a full scan of the extruder bar at your best resolution in both real color and thermal—”

“Doing that, real color and thermal, I’ll need to close a bit more to get the best resolution.”

Although he was focused on the technical video going into Camera 1, he made sure that Camera 2 stayed locked on Fiorella. He was shooting her through the expanding ball of silvery chaff, and though he knew at the back of his mind that the chaff represented a disaster, it was also one of the most beautiful things he’d ever seen, the metallic strands writhing in the sunlight, with the blue-marbled Earth far below: and Fiorella’s egg right in the center of the shot.

As an honorary techie, he was appalled. Something had gone badly wrong. The test was clearly a failure. Was it a fatal one, in terms of either the mission or the people? He switched his headset over to the engineering channels the Red had been recording and caught the stream of reports coming into the chief reactor manager and Becca Johansson and quickly caught up on the status.

No permanent damage done to the station or to the mission, no human injuries of any kind, though Johansson sounded mightily pissed off. From what he could tell, the ribbon guidance system had cratered. As the speed of the ribbons increased, an instability appeared. From what he could hear over the audio links, the engineers didn’t know if it was vibration in the extruders or some sort of feedback loop between the ribbons and the sensors and the control magnets, or if the computer controls hadn’t been up to the task.

Whatever, those fast-flying ribbons had developed wobbles and the wobbles had grown uncontrollably until finally the whole control system collapsed under impossible demands and the ribbons started flying off in all directions.

He’d reached the end of the extruder bar and he clicked over to the engineering channel and asked, “You need another run on the extruder bar?”

Johansson came back almost immediately.

“If you can, give me a thermal image of the end of the bar where the instability started. Just leave it there for a while. Two minutes, anyway.”

“Doing that now,” Sandy said.

Fiorella called, “I don’t want to seem crass,” she began.

“Never bothered you in the past,” Sandy said.

“I’m laughing inside,” she said. “Tell me that you got at least a few seconds of our eggs floating in the background, when the thing blew.”

“Camera two was locked on you the whole way, and still is. The chaff is clearing out. If you want to motor over this way, we could do a tracking shot of you coming in, right up to your face. Dodge around a few pieces of the metal—that should look pretty spectacular.”

Fiorella asked, “Joe, can we do that?”

“Yeah, we can do it, but I still say he’s a crazy motherfucker.”

Crazy motherfucker I might be, Sandy thought, and it was all chaos theory in motion and one hell of a screwup: but, ohmigawd, that’s entertainment!