Project Solar Sail

by Arther C. Clarke

  “We people on the Lagrange colonies are just more casualties in another war. Our numbers are already written in their books. We are on our own.”

  Ramis had a frightening, claustrophobic realization of just how isolated they were on the colonies, stranded with no ships even to get to each other or back to Earth. The last shuttle transport had been hijacked by a gang of desperate people from Orbitech 1 and had crash-landed near Clavius Base on the moon. The Lagrange colonies’ few feeble attempts at self-sustenance—their symbolic but tiny hydroponic fields of wheat, corn, and rice—would not be enough to last them very long.

  But the Filipino bioengineering mavericks kept the people on the Aguinaldo alive, just barely, with a strain of experimental wall kelp and the sail creatures developed years before.

  The wall kelp tasted bland, but it was better than no food. Ramis and all the others had been eating nothing else for four months now, ever since the supplies from Earth had dwindled away. Cut off and isolated at L-4, the Aguinaldo had listened to the transmissions from Orbitech 1. The pitiful pleas for help growing gradually more desperate; the grim news of starvation, rioting, and even hints of cannibalism. The Soviets in their colony had fallen silent soon after the war. The Filipino colonists could do nothing but listen—they had no ship to send, no help to offer.

  Until now.

  Inside the sail creature, looking at Orbitech 1, Ramis felt as if he were falling, falling down toward the station. Space gave him no reference, no horizon, no gravity. The direction “down” was where things fell when you dropped them . . . but out in space, everywhere was “down.”

  Ramis groped out to touch the walls of the cyst, searching for stability, trying to fight off the sickening vertigo. He would be falling forever because there was no place to land.

  He squeezed shut his eyes. Sleep came, and with it, tumultuous memories . . .

  ###

  Being at Jumpoff, at one end cap of the Aguinaldo’s cylinder, was like standing at the bottom of a gargantuan well. The lightaxis stretched above as Ramis floated at one end of the zero-G core. He squinted to see the other end, ten kilometers away. The column of fiberoptic threads making up the lightaxis glowed with raw sunlight. Clusters of children played in the core, punctuated by sail creatures darting in and out, keeping the youngsters away from the lightaxis. Adults circumnavigated the rim, leaping from bouncer to bouncer in an ever-accelerating race around the circumpond.

  Living areas curled up around the cylindrical colony’s side, snaking across the fields, the rice paddies, stadiums, streams, and the circumferential Sibyuan Sea. Fields of taro and abaca dotted the living areas. Experimental sectors of wall kelp covered the remainder of the Aguinaldo, allowing little of the colony’s metallic structure to show.

  Revolving around the long lightaxis, Ramis’s whole world seemed as though it might collapse and fall to the center. The sight always made him dizzy.

  Pushing off, Ramis closed his eyes. As a child, he could always escape here, be alone. His thoughts drifted to the Council of Twenty. After all the talk, all the rhetoric, they finally had decided to try to help the L-5 colonies.

  Dr. Sandovaal had bullied them to try a desperate attempt, exploiting the sail creatures. The creatures had both mitochondria and chloroplasts within their cell walls. They were both plant and animal, a one-in-a-million accidental success from the bioengineering labs. Somehow everything had worked exactly right: everything fit together, everything functioned as it should.

  And when exposed to vacuum, Sandovaal argued, the creatures would still metabolize, using the hard solar radiation for direct photosynthesis. It would be the sail creature’s last gasp for survival—its fins would elongate in a feeble attempt to maximize its light-collecting area for photosynthesis. The sail creatures would metamorphose and take on their plant attributes, becoming a largely immobile receptor of solar radiation.

  Working in vacuum, the bioengineers had attempted to accelerate the growth of three of the creatures. As the Aguinaldo’s chief scientist, Dr. Sandovaal directed the ejection of the first anesthetized creature. It had exploded from its own internal pressure, unable to compensate for the vacuum fast enough.

  On the next attempt, they did not drug the second creature into complete dormancy—and it successfully expanded in the cold vacuum. But its metamorphosis had been too fast, too violent, for the restraining hooks connecting it to the Aguinaldo. The sail creature had torn free and drifted away.

  Ramis was there peering out the window plates as two engineers wearing manned-maneuvering units jetted after the still-growing sail, but they could not recapture the creature and turn it around without damaging the thin membrane. The two engineers looked like tiny dolls as they floated back to the docking bay, side by side.

  But the third creature had survived the accelerated metamorphosis. The bioengineers oriented the sail creature’s proto-sails edge-on to the sun to prevent the solar photons from accelerating the sail before the process was complete. Day by day the creature’s fins spread out, becoming vast cell-thin sails, immense and opaque, hundreds of kilometers to a side, as the creature desperately tried to soak up light. The main bodily core became rigid and exceedingly tough, like an organic “hull.”

  Ramis would have to ride inside, go to the L-5 colony.

  President Magsaysay, Ramis’s mentor, had gone out of his way to be with the boy, trying to talk to him. But Ramis wanted to be alone, to think. After all, Ramis had been picked for the mission—he deserved some time alone.

  Now he ached for any company at all.

  ###

  “What we want to do is this, so pay attention, boy.” Dr. Sandovaal rapped on the surface of the stereotank with his old-fashioned pointer stick. The image in the tank jiggled, then focused again into a diagram of the Earth-moon system.

  “When we release you from the Aguinaldo, you will turn the sail so that it faces the sun, taking the full momentum of the solar photons. You will then be moving ‘backward’ in orbit, relative to L-4. In about three hours, this will provide enough braking to slow you from our normal orbital velocity down to three kilometers per second. You must then turn your sail edgewise. You will drop like a stone toward Earth, skim past it at a distance of about an extra Earth radius, and then head back up to where you started.”

  On the stereotank a blue dashed line appeared, tracing Ramis’s planned trajectory. “But while you’ve been going down and coming back up, the moon, L-4, and L-5 have been continuing their own orbits. By the time you return to the starting point, L-5 will be there instead of L-4.”

  Ramis studied the diagram. “So I am just killing time by going down to Earth? Waiting for the other points to change position?”

  President Magsaysay watched Ramis, looking troubled, but Ramis ignored him, keeping a brave, calm expression on his face. Sandovaal rapped his fingers on the polished tabletop. “Correct! Think of it as being on a merry-go-round. You are on one horse, which is the Aguinaldo. You hop off the merry-go-round, wait for the next horse to pass by—which is the moon—and then hop back on when the third horse comes into position. That is Orbitech 1.”

  “But how long is this going to take?” Magsaysay stared at the dashed blue line, as if counting time.

  “Nine or ten days, depending on how large we can grow the sail and how accurately the boy can maneuver with it. We cannot leave him out there any longer than absolutely necessary. His suit and the sail creature’s exoskeleton will provide little protection from the cosmic radiation . . . and we want to reach Orbitech as soon as possible.”

  Ramis remained silent for a moment, looking around the empty chamber. The room was large, dominated by a long meeting table surrounded by unoccupied chairs. Overhead, shadows of passing pedal kites and playing children crossed over the skylights of the chamber. Ramis set his mouth. “The sail creature—it will die, now that the metamorphosis has taken place?”

  “Eventually.” Sandovaal blinked his eyes at Ramis, as if wondering at the relevance of th
e boy’s comment.

  Ramis swallowed. “How long do I have?”

  “We cannot implant you too soon—the creature’s physical structure is still hardening, you see. Still forming a rigid sheath to keep the new sails in place. But the timing will be close. After we encyst you, the trip should take ten days.”

  “You told me that. I want to know how long the sail creature will live.”

  Sandovaal switched off the stereotank, letting the images fade back into the murk. As the lights came up, Ramis watched Magsaysay nod to Sandovaal. Sandovaal pursed his lips. “It will die within two weeks, or possibly less. We have too few data to be confident. However, we will provide you with hormone injections to induce nerve reactions—you should still be able to move its sails. If the sail creature ceases to respond before you reach Orbitech 1, you will not be able to steer. And then you will be trapped.”

  Magsaysay’s shoulders sagged and he started to speak up, but Sandovaal cut him off. “But it is still possible. I am confident.”

  The president did not look greatly consoled. He turned again to Ramis, as if pleading with him to change his mind. Ramis stood, his face expressionless as he pushed away from the meeting table. “Thank you, Dr. Sandovaal.” He strode from the room and headed for Jumpoff to drift alone in the core.

  ###

  Ramis was cramped, hot. The air in the cyst stifled him. The pain in his joints ached without relief. He felt dizzy most of the time now, sick to his stomach. Dr. Sandovaal had warned him that the suit might not protect him enough from the hard radiation—and he would have no chance if a large solar flare occurred. He envisioned a long time recovering from this journey . . . if he survived at all.

  The sail creature hardly responded to Ramis’s course-adjusting maneuvers anymore. Reluctant, Ramis had to resort to deep, vicious jabs with the knife to get the creature to turn even a little.

  But the L-5 colony filled up most of the viewscreen, like a rotating dumbbell with two wheels spinning on a central axle.

  Ramis reached out and stroked the cyst’s inner membrane through the thick jungle of wall kelp growing unchecked inside the cavity. He didn’t know if the creature could feel him, or respond, but he continued to caress. It kept his hands occupied.

  Ramis conserved the batteries in his transceiver, using it only occasionally to send a signal to the L-5 colony; he had long ago passed out of range of the Aguinaldo. Magsaysay had promised that they would continue to transmit to Orbitech 1, telling them what to expect, how they could receive the life-saving supplies Ramis was bringing them. But the boy had no way of knowing if those messages had been acknowledged, or even received. Was anybody alive on the Orbitech colony?

  The wheels’ metallic surfaces glinted in the sunlight, causing bright flares and smears on the video screen. The colony’s observation windows glimmered with light from the inside, naked and devoid of wall kelp. It looked strange to Ramis, but he could not focus the video camera enough to see inside.

  What if he found no one at all? How would he ever get back? He would never even get inside the colony unless someone opened the airlock and took him in. And the sail creature was almost dead—that left Ramis with no way back home.

  “Orbitech 1, I am almost to you.”

  A loud meaningless crackle returned, but Ramis kept trying. They had to know he was coming. No one could mistake the sight of the vast organic solar sail drifting closer every day. He almost missed it when a weak voice came from the speaker. He knew his transceiver battery was almost dead.

  “. . . tech here . . . Ready . . . receive you.”

  As Ramis caressed the inner membrane of the sail creature, he silently willed the behemoth to remain alive just a short while longer.

  ###

  They rapidly closed on the L-5 colony. To slow him down enough so that impact with the colony would not kill him, Ramis had to collapse the sail creature’s broad and beautiful sails, draw them in to cushion him from the crash.

  Orbitech 1 gleamed on the monitor. He knew which end would have the docking bay, where the people would be waiting for him. He watched the wheels turning, one clockwise, the other counterclockwise. With each rotation of the colony, the creature drifted nearer. Ramis swallowed. The picture on the monitor screen blurred from his tears.

  Moving slowly, Ramis withdrew the pressurized vial from its cellophane pack, along with the tiny explosive-driven carrier pellets.

  He had to judge when the time was right. He had to know, and he could not hesitate. If he botched this up, then he would have done all this for nothing and made a martyr of himself as well. And more important, he would have extinguished the last hope of survival for those inside the L-5 colony.

  He could see the details of the airlock now, the Orbitechnologies corporate logo, the viewing windows on either side of it. The colony swelled to fill the entire video screen.

  Ramis felt the sweat of his fingers inside the gloves, holding the vial of pressurized trigger hormone, slick against the Mylar of his suit. He rammed the hypodermic cartridge inside the sail creature’s membrane and ejected its contents.

  Reacting with incredible slowness, the sails collapsed. They drew in toward the cyst, lumbering together as a butterfly might bring in its wings. The cell-thin sails stretched scores of kilometers out in front of the cyst. With the sudden movement wispy fragments tore away, rippling like the shrouds of a ghost.

  The sail creature’s crumpled body struck the L-5 colony, pushing against the tattered ends of its sails. Ramis felt the impact ripple through the creature’s flesh, but the boy was padded by the curtains of wall kelp and kilometers of sail. The minute-long collision dragged on; it seemed to take hours.

  He felt himself drifting back again, rebounding. Suddenly, panic burned through him. If he drifted out of the colony’s grasp, then he would be stranded again, without even the sails for maneuvering.

  The video monitor was dark; outside, the cameras had been covered up by folds of the collapsed sails. Ramis sealed his helmet, made certain that the sail creature embryos were protected in their airtight canisters, then took out his knife.

  He had to get out; he had to do something before it was too late. Ramis shouted again into the transmitter. Nothing. He saw that he had left it on—the battery was dead.

  He hesitated only a moment, then plunged the knife into the tough membrane, trying to cut his way out of the cyst. When the blade broke through to the outside, decompression almost ripped the knife out of his hand. The outrushing air tore the gash open wider, but acting as a jet to push him back toward the colony. Ramis continued to saw with the knife edge. Crystals sparkled as the humidity inside the cyst flash-froze, layering everything with a thin coating of ice. One of the wall-kelp bladders burst and froze in the same second.

  Ramis could see partly through the opening in the cyst, and then he felt a tug on the carcass of the sail creature. He peered out and saw several figures in spacesuits near him, attaching a tether to keep him from drifting with the recoil from impact.

  The boy felt drained with relief, but he could not yet relax. He kept hacking with his knife, trying to make the opening wide enough for him to emerge. One of the suited figures swam up in front of him, face to face, nodding.

  Ramis was startled to see behind the faceplate a thin, fearful expression; but the face bore a look of hope and wonderment that cut through weeks of despair.

  The boy emerged from the hulk of the dead sail creature, feeling like a newborn coming out of a womb. He turned back to see the creature’s shriveled remains. The once-magnificent sails now looked as if someone had crumpled up a gigantic wad of paper and tossed it aside.

  Sharp needles of pain struck him in his joints, and uneasy tremors raced through his muscles. But it felt wonderful just to move again, to stretch, to be free. He stared down and saw only an infinity of stars, not the curved wall of the Aguinaldo as he was accustomed to seeing. If he started to fall, he would keep falling forever and ever . . .

  Dizzy, he loo
ked up at the large observation windows on either side of the airlock. Pressed against them he saw scattered faces with large gaps between them—pitifully few faces. They looked as gaunt and anxious as the one he had seen inside the suit.

  One of the men wrestled the knife from his hand. Ramis was too weary to struggle, so he released it and kicked toward the airlock. He tried to make motions to show them what they needed to get from the cyst. He saw them taking out the sail creature embryos; they also needed to remove the wall-kelp nodules. The wall kelp would survive for some time in the vacuum, but they needed to bring it inside as soon as possible.

  As he drifted through the maw of the towering docking-bay doors, another space-suited figure took his arm and directed him to one of the doors at the wall. He supposed it was an elevator shaft. His legs continued to tremble, and he felt ready to dissolve inside his suit.

  Behind him, he saw the suited figures cutting at the dead creature’s crumpled sails, getting at its body core. The severed tissue-thin sails drifted away as the L-5 colony continued in its orbit.

  Though he felt incredibly weary and dizzy from his journey, Ramis waited by the elevator shaft and watched the other colonists bring in the wall kelp and embryos.

  The frozen kelp strands were still edible, and the central nodules would survive. His escort seemed impatient and urged him to enter the elevator.

  As the spokeshaft elevator descended, the chamber filled with air. Ramis could feel his weight increase as they traveled out to the rim of the wheel where the artificial gravity was strongest.

  His escort cracked open his helmet and indicated for Ramis to do the same. Ramis took a deep breath of the warm, stale air of the industrial colony. A potpourri of odors wafted past, very different from the humid stifling air of the cramped cyst. The smell was metallic, scrubbed clean—more artificial than the Aguinaldo’s.