Higher Education

by Charles Sheffield

  Deedee was still staring at the electronic layout diagram of the carrier. "Well, I don't. Everything looks just fine."

  "The carrier's fine. The ore blocks are fine, too."

  "So what's the problem?"

  "It's the shape of the blocks. I noticed they looked odd when we first came in. They have the right mass and density but they don't pack tight. There's too much space left between them."

  "So what do we do?"

  "We look for a better packing arrangement, one that fits the blocks together more tightly."

  Ten minutes of useless brainstorming was enough to prove that they would never find the answer by abstract thought. Under Deedee's direction the mining robot began to fit blocks one on another, turning them every way to seek the best fit of the irregular faces. The right answer, when they finally reached it, seemed absolutely obvious. With one particular arrangement the sintered blocks keyed in together tightly and seamlessly.

  Then the carrier had to be unloaded, and the whole operation begun over. This time the five hundred tons fitted with room to spare. Deedee came over to watch the last block go in. She ordered the mining robot in on top of it before she closed the hatch.

  "Think that was the Gossage surprise?" she said as she followed Rick into the ore carrier's control room.

  "The first one, maybe. Nobody said he keeps it to one. There could be another right here."

  They examined the carrier's status indicators one by one with enormous care, until at last Deedee shrugged. "We can't stay here forever just looking. Do it, Luban."

  Under Rick's nervous control the carrier crept forward out of the loading chamber and into open space. By all Belt standards the journey was a trivial one: a couple of hundred kilometers through unobstructed vacuum, to rendezvous with another body having negligible velocity relative to CM-2. The training facility's refinery was in an essentially identical orbit around the Earth-Moon system.

  That fact did not offer Rick any sense of security. He was keyed tighter than he had ever been until at last the carrier was snugly into the refinery's dock. Then it was Deedee's turn. She unloaded the robot and it carried the sintered ore blocks one by one to the refinery's gigantic hopper.

  They stared at each other as the final block went in.

  "Smooth," Deedee said at last.

  "Too smooth?"

  "There's no such thing."

  "You know what I mean." Rick stared at the distant bulk of CM-2, its outside lights clearly visible from the refinery. "Let's get back. If there are surprises here I don't want to hang around and wait for them to find us."

  He checked the fuel as he switched on the drive. More than enough. He could cut off power after a couple of minutes, coast all the rest of the way to CM-2, and finish with a little fuel to spare. And even with the delay in loading they had plenty of time to complete the assignment before the end of the work period. Maybe the only Gossage surprise was the sintered block shape.

  That comforting thought was still in his head when he realized that the star field outside was slowly rotating. Instead of heading straight for CM-2 the ore carrier was yawing, turning its blunt prow farther and farther away from the planned heading.

  Rick slapped at the controls and turned all thrust power off.

  "What's wrong?" Although he had not said a word, Deedee caught the urgency of his movement.

  "Drive. We're crabbing." Rick was already calling up onto the control display the rear perspective layout of the carrier, to show the six independent but balanced units that provided the ship's drive. "Something's wrong with one of the modules. We're getting no thrust from it."

  Deedee was watching the changing starscape in the front port, noting the exact direction of rotation of the ship.

  "We're tilting to the right and down." She touched her gloved hand to the display, one finger on the stylized image of a module. "If it's a problem with just one thruster, it has to be this one. Any of the others would turn us in a different direction."

  "Agreed."

  "So turn off the opposite one of the six, directly across from the bad one. Do it, Rick! That will balance us again."

  "I can't." Rick gestured at the control panel. "The thrust modules are not separately controllable. It's all or nothing."

  "So what do we do?"

  Rick did not answer. He had called up a section of the ship's manual onto the display. More than anything he had ever wanted in his life, he wanted to read that manual. And he couldn't. The words were too long and unfamiliar, the sentences seemed too complex. He strained to understand, willing the words to make sense. And still he couldn't read them. The ship was drifting along, but CM-2 was not directly ahead. Their present course would miss the planetoid.

  "Help me, Deedee." Rick was sweating inside his suit. "Help me to figure this out. The manual will tell us what to do. It has to. Help me to read. You read better than me."

  "I don't. You know I don't." But Deedee was following Rick's lead, reading each word on the screen aloud, stumbling over the hard ones.

  They struggled on, reading in unison, cursing unknown words, correcting each other. Until finally Deedee cried out and pointed at the display, "Attitude. That's what that word is. Attitude control. This is the part we want. Come on, Rick. Read it!"

  Rick was certainly trying; but he had already discovered that simple need and urgency didn't let you read any faster. They ground on together, word by word, through the next three paragraphs. And at a certain point, groaned in unison.

  "It's obvious!" Rick slapped his knee with his gloved hand.

  "And we're idiots." Deedee repeated the important sentences, gabbling them on the second time through. " 'In the event of thrust module imbalance, the carrier must be returned to the main maintenance facility.'—Yeah. Thanks a lot.—'However, should a thrust module fail and a temporary course adjustment be necessary in space, this can easily be performed by the use of minor lateral control jets. These can be used to spin the ship about its long-it-ud-in-al'—hell of a word—'axis, so that the mean thrust is maintained in the desired direction. The same elementary technique can be used to make general direction adjustments, by halting longitudinal rotation after any suitable angle.' Do it, Rick!"

  "I am doing it." Rick was already using the lateral thrusters, turning the ship about its main axis to bring the failed thruster module onto the opposite side. "I'm going to have to juggle this. If I thrust too long in the other direction we'll swing too far and miss the base on the other side."

  "Do it in—little bits." The main thrusters fired, this time in a pattern as jerky as Deedee's speech. "We still have plenty of time. Go easy. You can afford to go easy."

  "I will go easy. Trust me."

  Rick was eyeing CM-2 as it swung back into view in the forward port. Under his control the drive was stuttering uneasily on and off while the ship rotated unevenly about its main axis. He knew exactly where he wanted to go—into the hard-edged aperture that sat like a bullet hole in the planetoid's rugged side. But getting there, exactly there, was another matter. It was another half hour before Rick could turn off all power, shiver in released tension, lift his hands from the controls, and wait for the magnetic arrest system to guide the carrier to a berth within CM-2.

  Before the grapple was complete Deedee was out of her seat and heading for the lock. "Come on. We have to go."

  "What's the hurry?" Rick was moving more slowly, stretching cramped hands as he eased himself from the pilot's chair. "You said we had plenty of time."

  "I lied." Deedee was already in the lock, waiting impatiently. "I didn't want you worrying about time when you were flying the carrier. But it's going to be touch and go."

  Rick took a glance at his helmet chronometer and leaped for the lock. "We only have twenty-three minutes left!"

  "I know." The lock was cycling. "We can do it, though—so long as we don't meet any more snags."

  They flew side-by-side from the docking berth to the mine entry point to CM-2. "Say, two minutes each en
d." Rick hit the entry combination. "Twelve minutes to get through the tunnels—that's about as fast as we can go. But we still have a seven minute cushion." He keyed in the entry combination again. "What's wrong with this thing? It shouldn't take this long."

  "The power has been turned off." Deedee pointed to the telltale set in the great door. "And it's too heavy for manual operation."

  "Turkey. The bastard. He's screwed us. We can't get in."

  "Then we'll have to go around. Or use one of the side tunnels?"

  "No good. They all lead outside, not to the training facility."

  "That's our answer." Deedee had turned. "We can go right around the outside. Don't waste time with that door, Rick. Come on! We're down to twenty-one minutes."

  She led the way, zooming at maximum suit speed for the open entrance of the mine loading chamber. Rick, close behind, did the calculation. They had to make their way right around CM-2 to almost the opposite side of the planetoid. Say, three kilometers. If they could average ten per hour, they would do it. If not. . .

  All Rick could think of was that early this morning he had made Deedee sit down and eat breakfast when she was hyped up and raring to go. If they were too late now, it was his fault.

  They came to the edge of the loading chamber and burst out from the darkness. As Deedee, still ahead of Rick, emerged into full sunlight she reversed suit jets and came to an abrupt dead halt.

  "Keep going, Dee. I'm right behind you."

  But she was not moving. "Listen to your dosimeter, Rick."

  He became aware of a tinny rattle in the background. It was his suit's radiation monitor, operating well above the danger level.

  "Back inside." And when he hesitated, "We have to, Rick. Right now." She had him by the arm of his suit, towing him. "It must be a solar burst, a sudden one and a big one. We're safe enough as soon as we get some rock shielding around us."

  They were already out of sight of the Sun. Safe enough. And failed. Rick glanced at his chronometer. Eighteen and a half minutes.

  "Deedee, we wouldn't be outside for very long. I'll bet the integrated dose would be small enough, it wouldn't harm us."

  "Maybe. But are you sure?"

  He wasn't. Worse than that, he didn't know how to make sure. The calculation couldn't be very difficult, no more than a formula and a few simple summations. Jigger would probably have done it in his head. But Rick didn't know how to do it at all. He groaned.

  "We're safe enough here." Deedee had misunderstood the reason for his misery. "Rock is a perfect shield."

  "I know. I don't want a shield. I want to beat that goddamn deadline."

  "We can't possibly. A solar storm could last for days, and we have only seventeen minutes left."

  Rock is a perfect shield.

  "Dee, we still have a chance. The sun is shining almost directly into the loading chamber. The training facility is on the opposite side. We can go through a side tunnel to a point where we're out of direct sunlight, then jet the rest of the way outside shielded by CM-2 itself."

  "Sixteen minutes. We'll never do it in time." But she was following Rick as he plunged back into the dark interior. He picked one side tunnel and went into it without hesitating. Fortunately Deedee didn't ask why Rick knew so well the network of passages and chambers that criss-crossed the interior of CM-2. He certainly wasn't going to mention it or the disastrous episode it had led to with Gina.

  The passageways had been designed for mining rather than rapid travel through them. The trip through the interior seemed to take forever. At last Rick and Deedee were at the surface again, about a quarter of the way around the planetoid, but they were running out of time. Five minutes left. A kilometer and a half to go on the outside, hugging close to CM-2 to avoid the solar flare. It didn't sound far. But it meant averaging eighteen kilometers an hour. You couldn't do that. Not in a suit, zooming around the irregular exterior of a planetoid.

  Rick knew it. Deedee probably knew it, too. Neither said a word as the final minute flashed past and the deadline was missed. They kept going, bitterly, all the way to the lock that would lead them into the training facility.

  As the lock opened, Rick halted. "No good. Six minutes late. Sorry."

  "I know." Deedee came to his side, put an arm around him, and hugged him. She leaned her helmet against his as they moved into the lock together. "We gave it our best shot. Nobody can take that away from us."

  The lock pressure equalized. They reached up to remove their helmets as the inner door opened—and found themselves staring at the anxious face of Turkey Gossage. Turkey glanced at once at his watch.

  "Don't say it." Rick moved out of the lock. "Six minutes late."

  "I wasn't going to. Did you come around the outside?"

  "Part of the way." Deedee came to stand at Rick's side.

  "Let me see your dosimeters so—"

  "No problem. We did the first part in the interior, and we only came outside when CM-2 was shielding us from the Sun."

  "Smart move." Gossage relaxed visibly. "Of course, even in the Sun the dose you'd have received in the short time you were there would have been tolerable."

  "We weren't sure." Rick was suddenly more tired than he had ever been. "We didn't know how to calculate it."

  "I can show you that in five minutes."

  "I'm sure you can. But not today, sir, if you don't mind." Rick slumped against the chamber wall and allowed his arms and legs to go limp. "We did our best, we really did."

  "And we came so close." Deedee flopped down by Rick's side. "If there had been one less problem to solve—just one."

  "I see. Would you agree with that, Luban?" Turkey seemed more amused than sympathetic.

  "Yes. But I don't see why it matters."

  "It matters very much. To me, at least." Gossage squatted down so that he was facing the two of them. "You see, it's not every day that people mistake me for a deity." And, when Rick and Deedee stared at him with dull and exhausted eyes, "I gave you a test that I thought would stretch you right to your limits. If you did everything right, and fast, and clean, you could make it back before the deadline—just. I rigged the shape of the sintered blocks. I fixed the drive so it would go wonky on the return trip. I turned off the power on the main entry door so you couldn't get back inside and would have to come around the outside. But if there's one thing that even Turkey Gossage can't do, it's to arrange a solar flare for his special convenience. I'd have to be God Almighty to do that. The flare wasn't in my plans, any more than it was in yours."

  He reached out, taking Deedee and Rick's right hands in his. "If it hadn't been for the flare you'd have beaten your deadline with time to spare. That's good enough for me. You did well, better than I expected. You've passed. Now, don't go to sleep on me!"

  Rick and Deedee had simultaneously closed their eyes. They showed no sign of opening them again.

  "All right." Gossage stood up. He was still holding their hands and his movement lifted them to their feet. "You've passed the practical test, the pair of you, but you don't seem to care. Eat and rest, rest and eat. We'll talk later." He released them, turned, and headed for the tunnel. As he reached it he added, without turning his head, "Just don't get cocky. You still have theory finals—and I guarantee they'll be tough. You won't have things this nice and easy all the time."

  Chapter Ten

  TURKEY Gossage was as good as his word and better. The theory final was more than tough. It was murderous. Rick staggered out of a private cubicle—no chance to "borrow" your answers on CM-2—and saw his own despair mirrored on everyone's face. They had been asked questions far beyond anything taught in class. Jigger Tait's early warning had been right: if you didn't learn how to browse all around a subject, you were in trouble at Vanguard Mining.

  Give the formula for the velocity, v, achieved by a ship accelerating with acceleration a for a time t.

  That was fair. Turkey had pounded the simple formula, v = at, into their heads a dozen times. He said they had to remembe
r it for the rest of their lives.

  But then came the zinger: State circumstances when the formula that you have just given does not apply.

  That had definitely not been mentioned anywhere, in any lesson. Rick had a vague feeling that things went wrong if you kept on accelerating until the calculated velocity was near the speed of light. He knew for sure that the formula couldn't work if the answer you got was more than the speed of light, because nothing could go faster than that. But he had absolutely no idea what the right relation between speed and acceleration would be in such a case.

  Stating all those thoughts, clearly and precisely, was just about impossible. Rick decided that he had waffled. Whoever listened to his spoken answer would know it. It all came back to what Mr. Hamel had said on the far-off day Rick had been kicked out of school: it's a lot easier to be exact when you write something than if you try to speak it.