Project Solar Sail

by Arther C. Clarke

  Muldoon stared at the woman, noted she was young and pretty, and gestured at her to sit down. He poured everyone a liter of orange juice. We competitors sweat away seven or eight kilos, pedaling a Stage, and we have to make sure we start out flush-full with liquids. Tomas took the opportunity to slide away while Muldoon was pouring. He’d had his juice, and some of the other competitors who were still straggling in might have a less enlightened attitude toward Tomas’s innovation of the previous Stage.

  “D’you understand how we change directions round in the middle of each Stage?” Muldoon asked the reporter. One reason Ernie is so popular with the Press is that he’s never too busy to talk to them and explain to them. I noticed that now he had her hooked he had dropped the stage-Irish accent.

  “I guess so. But I don’t understand why. You’re out in empty space, between the Stage points, and you’ve pedaled hard to get the wheels rotating as fast as you can. And then you shift everything around!”

  “Right. An’ here’s the why. Suppose the rider—say, Trace here, the likely lad—hasn’t reached the halfway point yet, and let’s for the moment ignore any fancy maneuvers at Stage turn points. So he’s pedaling like a madman—the only way he knows—and the wheels are whizzing round, and he’s built up a voltage of something respectable on the rotating Wimshurst disks—say, a couple of million volts. That voltage goes into accelerating the ion stream out of the back of the bike, eh? The faster he pedals, the higher the voltage, the better the exhaust velocity on the ion drive, and so the faster goes our lad Tracy. And he’s got to get that exhaust velocity as high as he can, because he’s only allowed fifty kilos of fuel per Stage, total. All right?”

  “Oh, yes.” The lady looked into Muldoon’s slightly squinty eyes and seemed ready to swoon with admiration. He beamed at her fondly. I was never sure that Ernie Muldoon followed through with a woman while we were riding the Tour—but I’m damned sure if he didn’t have them between Stages, he saved up credits and used them all when the Tour was over.

  “All right.” Muldoon ran his hand out along the tabletop. “Here’s Trace. He’s been zooming along in a straight line, faster and faster. But now he gets to the halfway point of the Stage, an’ now he’s got to worry about how he’ll get to the finish. See, it’s no good arriving at the final docking and zooming right on through—you have to stop, or you’re disqualified. So now Trace has a different problem. He has to worry about how he’s going to decelerate for the rest of the run, and finish at a standstill, or close to it, when the bike gets to the docking point. The old-fashioned way—that means up to seven years ago—was pretty simple. Trace here would have turned the whole bike round, so that the ion drive was pointing the other way, toward the place he wanted to get to, and he’d keep on pedaling like the dickens. And if he’d planned well, or was just dumb lucky, he’d be slowed down by the drive just the right amount when he got the final docking, so he could hit slap against the buffers at the maximum permitted speed. Sounds good?”

  She nodded. “Fine.” I didn’t know if she was talking about the explanation, or Ernie-the-Lech Muldoon’s hand resting lightly across hers. “But what’s wrong with that way of doing it?” she went on. “It sounds all right to me.”

  Someday they’re going to assign reporters to the Tour du Système who are more than twenty-two years old and who have some faint idea before they begin of the event they are supposed to be covering. It will ruin Muldoon’s sex life, but it will stop me from feeling like an antique myself. All the young press people ask the same damned questions, and they all nod in the same half-witted way when they get the answers.

  I wanted to see how Ernest handled the next bit. Somehow he was going to have to get across to Sweet Young Thing the concept of angular momentum.

  “Problem is,” he said, “while the wheels are spinning fast, the bike don’t want to turn. Those wheels are heavy glassite disks, rubbing against each other, and they’re like flywheels, and so the bike wants to stay lined up just the way it is. So in the old days, the biker would have to stop the wheels—or at least slow ’em down a whole lot—then turn the bike around, and start pedaling again to get the wheels going. All the time that was happening, there was no potential difference on the Wimshurst’s, no ion drive, and no acceleration. Big waste of time, and also for the second half of the Stage you were flying ass-backwards. So I did the obvious thing. I mounted a double ion drive on my bike, one facing forward, one facing back—turned out that the rules don’t quite say you can’t have more than one drive. They only say you can’t have more than one ion drive on your bike in use at one time. They don’t say you can’t have two, and switch ’em in the middle of the Stage. Which is what I did. And won, for about two Stages, until everybody else did the same thing.”

  “But what was it that Tomas Lili did? He seems to have come up with something new.”

  “He installed an ion drive that had more than just the two positions, fore and aft. His can be directed in pretty much any way he wants to. So, first thing that Tomas did on the last Stage, he went off far too fast—at a crazy speed, we all thought. And naturally he got ahead of all of us. Then what he did was to direct his ion beam at whoever was close behind him. The ions hit whoever he was pointing at—me, or Trace, or one of the others—and just about canceled out our own drives completely. We were throwing a couple of tenths of a gram of ion propellant out of the back of the bike at better than ten kilometers a second, but we were being hit on the front by the same amount, traveling at the same speed. Net result: no forward acceleration for us. It didn’t hurt us, physically, ’cause we’re all radiation-shielded. But it slowed us. By the time we realized why we were doing so badly, he was gone. Naturally, Tomas wasn’t affected, except for the tiny bit he sacrificed because his exhaust jet wasn’t pointing exactly aft.” Muldoon shrugged. “Neat trick. Works once—next time we’ll stay so far out of his wake he’ll lose more forward acceleration turning off-axis to hit us than he’ll gain.”

  “You explain everything so clearly!” Their hands were still touching.

  “Always try to help. But we’ve got to get ready for the Stage now. Will you be there at the finish?”

  “Of course! I wouldn’t miss it for anything.”

  Muldoon patted her hand possessively. “Then why don’t we get together after it, and we can go over the action together? Next to last Stage, there ought to be fireworks.”

  “Oh, yes! Please.”

  As we left for the start dock, I shook my head at Muldoon. “I don’t expect any particular fireworks today. No tricky course change, no solar flares—it should be the tamest leg of the Tour.”

  He stared back at me, owl-eyed, “And did I say the action would be on the course, boyo?”

  We walked side by side to the main staging area. In twenty minutes we would be on our way. I could feel the curious internal tension that told me it was Tour-time again—more than that, it was the final Stages of the Tour. Something in my belly was winding me up like an old-fashioned watch. That was fine. I wanted to hang there in that start space all ready to explode to action. I touched Muldoon lightly on the shoulder—Good luck, Muldoon, it meant; but don’t beat me—then I went on to my station.

  There was already a strange atmosphere in the preparation chamber. As the Tour progresses, that strangeness grows and grows. I had noticed it years ago and never understood it, until little Alberto Maimonides, who is probably the best sportswriter living (my assessment) or ever (his own assessment), sampled that changing atmosphere before the Stages, and explained it better than I ever could. Either one of Muldoon’s tree-trunk thighs has far more muscle on it than Maimonides’s whole body, but the little man understood the name of the game. “At the beginning of the Tour,” he said to me one day, “there are favorites, but everyone may be said to have an equal chance of winning. As the Tour progresses, the cumulative time and penalties of each rider are slowly established. And so two groups emerge: those with the potential to win the whole thing, and those wi
th no such potential. Those two different potentials polarize the groups more and more, building tension in one, releasing tension in the other. Like the Wimshurst disks that you drive as you turn the pedals, the competitors build up their own massive potential difference. Beyond the halfway mark in the Tour, I can tell you in which group a competitor lies—without speaking a word to him! If a rider has a chance of winning, it is seen in the tension in neck and shoulders, in the obsessive attention to weather data, in the faraway look in the man’s eyes. I can tell you at once which group a rider is in.”

  “And can you—” I began.

  “No,” he interrupted me. “What I cannot do, Trace, to save my life, is tell you who will win. That will be, by definition, the best man.”

  I wanted to be that best man, more than I had ever wanted anything. I was thinking of Alberto Maimonides as I lifted open the shell of my bike and began to inspect the radiation shielding. It was all fine, a thin layer in anticipation of a quiet day without much solar wind. The final Stage was another matter—the forecasts said we would see a lot more radiation; but that was another day, and until we finished today’s effort the final Stage didn’t matter at all.

  The fuel tank came next. The competitors were not allowed to charge the fuel tank themselves, and the officials who did it always put in an exact fifty kilograms, correct to the microgram. But it didn’t stop every competitor worrying over the tank, afraid that he had been shortchanged and would run out of fuel in the middle of the Stage. People occasionally used their fuel too fast, and ran out before the end of a Stage. Without ion-drive fuel they were helpless. They would drift miserably around near the docking area, until someone went out and fished them in. Then they would be the butt of all the other competitors, subject to the same old jokes: “What’s the matter, Tish, got thirsty and been drinking the heavy water again?” “You’re four hours late, Sven, she gave your dance to somebody else.” “Jacques, my lad, we all warned you about premature ejaculation.”

  I climbed into the shell and checked my trajectory. It was too late to change anything now, except how hard I would pedal at each time in the Stage. It would need something exceptional to change even that. I had planned this Stage long ago, how I would pace it, how much effort I would put in at each breakpoint. I slipped my feet into the pedal stirrups, gripped the handlebars hard, looked straight ahead, and waited. I was hyperventilating, drawing in the longest, deepest breaths I could.

  The starting signal came as an electronic beep in my headset. While it was still sounding I was pedaling like mad, using low gears to get initial torques on the Wimshursts. After a few seconds, I reached critical voltage, the ion drive triggered on, and I was moving. Agonizingly slowly at first—a couple of thousandths of a g isn’t much and it takes a while to build up any noticeable speed—but I was off.

  All the way along the starting line, other bikers were doing exactly the same thing. There were various tricks to riding the Tour in the middle part of a Stage, but very little choice at the beginning. You rode as hard as your body would stand, and got the best speed as early as possible. Once you were moving fast you could relax a little bit, and let the bike coast. At the very end of the Stage, you made the same effort in reverse. Now you wanted to hold your speed as long as possible, to minimize your total time for the Stage. But if you had been too energetic at the beginning, or if your strength failed you at the end, you were in real trouble. Then you’d not be able to decelerate your bike enough. Either you’d shoot right through the docking area and whip out again into open space, or you’d demolish the buffers by hitting them at far more than the legal maximum. Both those carried disastrous penalties.

  After half an hour of frantic pedaling I was feeling pretty pleased. My leg was giving me no trouble at all—touch wood, though there was none within thirty thousand miles. I could see the main competition, and it was where I wanted it to be. Muldoon was a couple of kilometers behind, Rafael Rodriguez of the NASA team was almost alongside him, and Tomas Lili was already far in the rear. I looked ahead, and settled down to the long grind.

  This was a Stage with few tricky elements. During the Tour we started from low-earth orbit, went all the way to L-4 in a series of thirty variable-length Stages, and then looped back in halfway to the moon before we began the drive to Earth. Some Stages were geometrically complex, as much in the calculations as the legs. This one was the sort of Stage that I was thoroughly comfortable with. The only real variables today were physical condition and natural stamina. I was in the best shape I had ever been, and I was convinced that if my legs and determination held out I had everyone beat.

  Twenty-six hours later, I was even more convinced. We had passed the crossover point long ago, and I had done it without any complication. I could still see Muldoon and Rodriguez in my viewfinder, but they had not closed the gap at all. If anything, I might have gained a few more seconds on them. No one else was even in sight. There was a terrible urge to ease off, but I could not do it. It was cumulative time that decided the Tour winner, and Muldoon and Rodriguez had both started this Stage nearly a minute ahead of me. I wanted to make up for that today, and more. The yellow jersey might be enough for Tomas Lili, but not for me. I wanted the whole pie.

  I had taken my last liquid three hours ago, draining the juice bottle and then jettisoning it to save mass. Now my throat was dry and burning, and I’d have given anything for a quarter-liter of water. I put those thoughts out of my head, and pedaled harder.

  It turned out that I left my final sprint deceleration almost too late. Twenty-five kilometers out I realized that I was approaching the final docking area too fast. I would slam into the buffers at a speed over the legal limit. I put my head down, ignored the fact that my legs had been pumping for nearly twenty-seven hours straight, and rode until I thought my heart and lungs would burst. I didn’t even see the docks or the final markers. I guess my eyes were closed. All I heard was the loud ping that told of an arrival at legal speed. And then I was hanging on the handlebars, wishing some kind person would shoot me and put me out of my misery.

  My chest was on fire, my throat was too dry to breathe, my heart was racing up close to two hundred beats a minute, and my legs were spasming with cramps. I clung to the handlebars, and waited. Finally, when I heard a second ping through my helmet’s radio, I knew the second man was in. I looked up at the big-board readout. It was Muldoon, following me in by one minute and seventeen seconds. He had started the day one minute and fourteen seconds ahead of me on the cumulative total. I had won the Stage—and I was now the overall Tour leader.

  I groaned with pain, released my harness, and cracked open my bike. I forced a big grin onto my face for the media—more like a grimace of agony, but no one would know the difference—and managed to climb out onto the docking facility just as though I was feeling light and limber. Then I sauntered along to where Muldoon was slowly opening his bike. One cheery smile for the benefit of the cameras, and I was reaching in to lift him lightly clear of the bike.

  He glared up at me. “You big ham, Trace. What was your margin?”

  “One minute and seventeen seconds.”

  “Ah.” It was more a groan of physical agony than mental as he tried to stand up on the dock. His thigh muscles, like mine, were still unknotting after over a day of continuous effort. “So you’re ahead then. Three seconds ahead. And with a new Stage record. Damn it.”

  “Thanks. You’re just a terrific loser, Muldoon.”

  “Right. And it takes one to know one, Trace.” He did a couple of deep knee-bends. “What about the others? Where did they finish?”

  “Schindell came in two minutes after you. He’s about four minutes behind us, overall. Something must have happened to Rodriguez, because he’s still not in.”

  “Leg cramps. We were riding side by side for a long time, then he dropped way behind. I’m pretty sure he had to stop pedaling.”

  “So he’s out of the running.”

  We stared at each other. “So it’s
me an’ thee,” said Muldoon after a few moments. “Barring a miracle or a disaster, one of us will be it.”

  It! Overall Tour Winner! I wanted that so much I could taste it.

  Muldoon saw my face. “You’re getting there, Trace,” he said. “Muscle and heart and brains will only take you so far. You have to want it bad enough.”

  I saw his face, too. His eyes were bloodshot, and sunk so far back that they were little glowing sparks of blue at the end of dark tunnels. If I had reached a long way into myself to ride this Stage, how far down had Muldoon gone? Only he knew that. He wanted it, as much as I did.

  “You’re getting old, Ernie,” I said. “Alberto Maimonides says that the Tour’s a young man’s game.”

  “And what does he know, that little Greek faggot!” Muldoon respected Maimonides as much as I did, but you’d never know it if you heard them talk about each other. “He’s talking through his skinny brown neck. The Tour’s a man’s game, not a young man’s game. Go an’ get your yellow jersey, Trace, and show your fine profile to the media.”

  “What about you? They’ll want to see you as well—we’re neck and neck for overall Tour position. How long since non-team riders have been one and two in Tour status?”

  “Never happened before. But I’ve got work to do. Weather reports to look at, strategy to plan. You can handle the damned media, Trace—time you learned how. And I’ll tell you what.” He had been scowling at me, but now he smiled. “You look at all the pretty young reporters, and you pick out the one who’d be my favorite. An’ you can give her one for me.”

  He stumped off along the dock. I looked after him before I went to collect the yellow jersey that I would wear for the final Stage, and pose with it for the waiting mediamen. Ernie hadn’t given up yet. There was brooding and scheming inside that close-cropped head. He was like a dormant volcano now, and there was one more Stage to go. Maybe he had one more eruption left in him. But what could it possibly be?