Complete Short Fiction, page 233
The chance of landing on any one cast was presumably very small, though there was no way of calculating just how small. Feroxtant’s suggestion that this might become possible when the concept of direction was finally clarified by the advanced mathematicians was not really a serious prediction, since he had no real idea of what the theory was all about; it was more like the suggestions in Earth’s early twentieth century that radium might prove a cure for cancer and old age.
Wattimlan, therefore, gave no serious thought to what he would do if and when the Longline made starfall. It would be routine, anyway. He flew. He readied himself for his first openspace reversal with some uneasiness, but missed its time only slightly. The miss annoyed him as a reflection on his professional skill, but it was in no way dangerous; the Longline was suddenly retracing its outward path. There was none of the deceleration which a human pilot would have had to plan and experience; the concept of inertia was even stranger and more abstract to Wattimlan than that of direction—or would have been if anyone had ever suggested it to him. The only observable phenomenon marking the reversal was another burst of neutrinos, vaguely analogous to the squeal of tires from a clumsily handled ground vehicle but—unlike the time error or a tire squeal—not indicative of poor piloting.
In the sub-light universe, a simple direction reversal does not involve change in kinetic energy, except for whatever entropy alteration may be involved; equal speed means equal kinetic energy. In the tachyon universe, momentum is naturally as meaningless as direction, kinetic energy almost equally so, and the interactions between forces and the various fundamental particles follow very different rules. However, the rules were the ones Wattimlan knew, and the time interval between the reversal and reentry into the neutron star’s surface film was for him boringly uneventful. He landed.
Feroxtant was nowhere to be seen; he had apparently gone off either working or playing. Wattimlan decided to be pleased at the implied compliment to his competence rather than hurt at the suggested indifference to his welfare, and went through post-flight and pre-flight checks without waiting for his commander and instructor to appear. He made another cast, and another, and another . . .
“So pay up!” Sforza leaned back from the display tank which dominated the Manzara’s maneuvering console, and just barely managed to refrain from smirking.
Jeb Garabed, a quarter century younger and correspondingly less restrained, glared first into the tank and then at the two-liter silvery cube beside it. He didn’t quite snarl—the captain was also present—but there was a distinct edge to his voice.
“I should know better than to let myself get fooled by that old line about mechanical brains. I know that thing is made of doped diamond, but I didn’t realize how much weight the first word carried!”
Sforza lifted an eyebrow. “I don’t seem to appreciate your humor as much as I used to.”
“Don’t bother to put that eyebrow on top of your head. It would be conspicuous. I wasn’t trying to be funny.”
“That’s just as well. You—” Sforza cut himself off with an effort, and fell silent. For a moment each of the men wondered if he had said too much, as Garabed’s face and Sforza’s scalp both flushed.
Captain Migna Sarjuk listened to the exchange without too much concern; she knew both men well, and could tell that the jibes were not serious. When arguments became too frequent, of course, it was a temptation to separate the disputants for a few months by judicious watch-shifting; but it was possible to be too hasty with this solution. One could break up good working teams, and even run out of possible combinations. With over eighty people on the Manzara the latter seemed mathematically improbable, but since most of the possible combinations were in fact eliminated by conditions of specialty training it was not entirely impossible. The ship had spent eighteen months—subjective time—en route, would be at least that long going back, and might remain several years at this end of the flight line; the captain had no intention of running out of solutions to the most likely personnel problems any sooner than she could help. She waited silently, paying close attention to Sforza’s reactions; the younger man, she knew, would not lose his temper in her presence.
He didn’t. The young radiometrist caught himself in turn, grinned, and tossed a couple of time-slugs onto the console. Sforza gathered them up. Garabed half-apologized as he continued to stare into the display.
It was not a picture in the conventional sense. The three-dimensional presentation did show images of a number of celestial bodies, but they were festooned with numbers, vector arrows in various colors, and other symbols. To Sforza, it was a completely informative description of all the detectable objects within a light-day of the ship. Garabed would have felt happier with the images alone, stripped of the extra symbols. He could then have thought of it as a simple bead-and-wire model.
He greatly preferred the direct view of space from the Manzara’s observation dome, even though human perception was not really adequate for its analysis. For most of the trip it had been an unchanging Milky Way—unchanging, that is, except as his own intellect changed it. He had found he could change its appearance from a flat spray-paint job on a screen a few yards outside the dome to a more nearly correct, but far from complete, impression of infinite star-powdered depths. His home star had been fading throughout the journey, of course, though the change in a single day had been imperceptible except at the very beginning. It was now an unimpressive object about as bright as Polaris.
The Manzara’s target star was now overwhelmingly bright, and the human mind had no trouble accepting that it was far closer than Sol; but its white dwarf companion had only recently grown brighter than the sun the explorers had left some ten objective years before.
But Garabed could read the display symbols even if he preferred to visualize differently, and now one of them caught his attention. It was typical of him that he did not call immediate attention to it; his first reaction was to recoup his betting losses. At this distance, a few minutes’ delay in reporting a discovery would not be of importance to the ship’s safety—or, more important, to the captain. He continued the conversation, and even Sarjuk failed to catch any change in his manner.
“So I was wrong. It just means we’ll have to spend a year and a half of our personal time flying back—unless I turn right while we’re here.”
“I’ll cover another bet on that, if you like.”
Garabed shook his head. “I guess not. Now that real work is starting, I don’t need so much distraction—and probably can’t afford it. It was different on the way, when I needed amusement. Conning my way out of boring jobs by smart bets provided that—even when I lost, the jobs themselves made a change. Now it’s time to be serious, though, if you’ll pardon the pun. How do things look to you?”
The ballistician gestured toward the display into which Garabed was still staring. “There you are. Cutting drive didn’t make much difference. It adds up to what we’ve known for a couple of centuries, plus what we’ve picked up in the last few months. One type A main sequence sun, known since before human history began—with an unexplained, not to mention unproved, charge of having been red instead of white a couple of millennia ago. One white dwarf in a fifty-year orbit with it, known since the nineteenth century. Four high-density planets discovered by us in the last few weeks. No gas giants, which would be out where the white dwarf would perturb them hopelessly anyway. And no trace of the faster-than-light ship you were betting would be here from Earth waiting for us.”
Garabed shrugged. “It was still a reasonable bet. We have artificial gravity, and a field drive system which can be described as a space warp without lying too grossly. It still seems to me that those should ease us into FTL flight before I’m very much older.”
“In spite of the fact that both the gadgets you mention were developed on the assumption that Einstein was right? And that even the warp which makes a portable fusion engine practical is an Einstein application? I seem to be missing a rung or two in your ladder of logic.”
Garabed glanced at the captain before answering. “Yes,” he said after a moment. “In spite of that.”
“And in spite of the fact that this trip was only a political gesture to quiet the people who don’t think Earth is home enough? And that there were long, loud screams about the better things which could be done with the resources which went into the Manzara and her equipment? Why-should-we-explore-the-stars, practically-no-chance-of-life, a-waste-of-resources, we’ve-solved-all-our-real-problems, let’s-sit-back-and-live? You’ve heard it all.”
“Sure I have.” Garabed did not look at the captain this time. “But people are still curious—that’s what makes them people. Once we were on the way some of them were bound to want to find out what we’d see—first. It’s being human. You have the same drive, whether you want to admit it or not; I’ll show you.” He reached across and flicked off the display in the computer’s tank. “How sure are you that there’s nothing really unexpected to be found in the Sirius system? And would you bet there isn’t a clue to it in your data banks right now?”
The older man looked into the blank display unit, and thought. The kid might have seen something, though Sforza himself should have noticed anything important; it was certainly possible. On the other hand, Sforza had known the young con artist to bluff his way out of one or another of the ship’s less popular jobs on at least four occasions during the trip, three of them at Sforza’s own expense. Had there been anything surprising on the display? Something he should, of course, have seen himself?
The captain had come over to the ballistics console to look for herself, though she of course said nothing. She knew, far better than Sforza, that Garabed might not be bluffing.
The ballistician hesitated a moment longer, straining his memory with no useful result, and decided to take a chance.
“All right. Two hours’ worth.” He put the slugs he had just won on the panel before him. Garabed covered them with two more, and turned the display back on. For a moment there was silence.
“What was the time limit on this?” the older man finally asked. The captain, unseen behind him, smiled and slipped back to her own station, where she busied herself at the intercom. The instrument specialist paid no obvious attention to her; the smile on his face might have been simply one of triumph.
“No time needed. Look at the white dwarfs radial velocity.”
“I see it. So what? You wouldn’t expect it to match A’s. Even a fifty-year orbit means a few kilos per second.”
“Changing how fast?” asked Garabed pointedly.
“Not very—” Sforza fell silent again, glued his eyes to the display, and within a minute the eyebrows were climbing toward the desert above.
“It’s changing!”
“How right you are. Do you pay now, or calculate first?”
Sforza waved the slugs away with an impatient gesture of his head; his fingers were already busy. He didn’t stop to wonder why the velocity variation had not been spotted sooner; it was obvious enough. The axis of the previously unknown orbit must point almost exactly at the Solar system. The Manzara was now so close to the Sirius group that the A star and the white dwarf appeared fully forty degrees apart, and the ship was well off the line between Sol and the dwarf. Hence, there was a radial velocity component not previously detectable.
This clue to the line of the orbit axis permitted an assumption which would otherwise have been a wide-open guess in Sforza’s computation. He plugged it in, let the spectral sensors which Garabed kept in such good condition feed their readings and the Manzara s clock signals in after it, and waited until the display steadied. Then, and only then, did he speak.
“Take your pirated money, and call Physics and Policy—”
“They’re coming,” the captain interjected quietly. Sforza continued.
“The white dwarf is in a nearly perfect-circle orbit with something too small to see, but of comparable mass. The period is seven hundred seventy-two seconds. The dwarf is thirty-two thousand miles from the barycenter, orbital speed two hundred seventy-seven miles per second—”
“Miles?” queried Sarjuk. “I can sympathize with the Creative Anachronism urge, but—”
“Fifty-one thousand five hundred, four hundred forty-six. The invisible body’s radius vector is open until we can get a mass ratio, but can hardly be more than a few tens of thousands of kilometers. We have a dividend. It’s either a neutron star or—”
“Or nothing,” pointed out the captain. “It can’t be more massive than the total previously measured for Sirius B—point nine suns. Too little for a black hole.”
Garabed was nodding slowly, his face nearly expressionless, but both his companions could tell he was containing strong excitement. His only words, however, formed a terse question.
“New flight plan, Captain?”
The Manzara had been free-falling in an orbit intended to make a close swing past Sirius B, enter a slingshot transfer to A with a periastron distance from the latter of only a fifth of an astronomical unit, and a second sling to interception with the largest, outermost, and probably most Earthlike of A’s four planets.
Sarjuk was by training an engineer specializing in safety extrapolation, which naturally included administrative psychology and hence qualified her for her present command status. She was certainly no ballistician, but she knew what a change in orbit meant in terms of fuel reserve—which after all was a major safety factor for the Manzara. In this case, of course, a good secondary-school student could have performed the appropriate calculations.
“New flight plan, of course,” she agreed quietly. “But let’s hear what Physics wants before Mr. Sforza does any number work.” She swung her seat about as a dozen excited researchers entered the bridge, motioned them to the seats which ringed the chamber, and turned back to Garabed.
“Jeb,” she asked, “can you possibly get anything with real resolving power to cover this object? I know it must be small, but until we know just how small and just where it is we’re going to be crippled in any planning. Sforza can give you the direction from the dwarf to the orbit center, and you can search along the projection of that line with whatever seems likely to work best. Build something if you have to.”
Without waiting for the two men to get to work, she turned back to the newcomers and gave them a summary of the new information. They listened in near silence, their eyes never leaving her face until she had finished.
“How close can we get?” Tikaki and Distoienko spoke almost in unison.
“Will it take too much fuel to park beside it?” was the more thoughtful question from Dini Aymara, a warp theoretician. Tikaki answered instantly.
“Of course not! Look—it’s a binary, with the two bodies similar in mass. All we’ll need is maneuvering power; we can use an orbit which will transfer our energy to one of the bodies instead of slinging us away. When we do want to leave, we can slingshot out in the same fashion. We can get as close to the neutron star as you want—meters, if your experiments need it—”
“Three objections, Mr. Tikaki,” the captain spoke quietly still. “First, at a distance even of kilos, to say nothing of meters, not even our best cameras could get clear images—figure the orbital speed at such a distance. Second, neutron stars are likely to have strong magnetic fields, and there are plenty of conductors in this ship, starting with the main hull stringers. Finally, there is such a thing as tidal force. I will not permit this ship into a gee-gradient of more than five inverse-seconds squared, and only then if all main and backup artificial gravity units are in perfect condition. Mr. Sforza, what distance would that tidal limit mean from the two bodies?”
The ballistician had finished providing Garabed’s needed figures, and was able to answer the captain’s question almost instantly.
“For the white dwarf it would be somewhere inside; you’ll be worrying about other things first. For the neutron star, it of course depends on the mass, which we don’t—”
“I have it—at least, I have a respectable mass on the line you gave me, affecting the gravity-wave unit,” cut in Garabed.
“Line?” responded Sforza. The instrument technician supplied a set of numbers which the ballistician’s fingers fed into his computer as they came; a set of luminous symbols appeared in the display tank, and were translated at once. “Mass is point three eight suns. The tidal limit distance you want is a hair under five thousand kilometers—about three quarters of an Earth radius.”
The captain nodded, and glanced around the group. “I thought so. Gentlemen and ladies, the Manzara is half a kilometer long—not a point.” If she expected Tikaki to look properly sheepish or disgruntled she was disappointed. He simply nodded, and after a moment she went on. “Very well. If Mr. Sforza can warp us into a capture orbit without exceeding tidal and radiation limits, and without using more than five hundred kilograms of hydrogen, I approve a pass. If you can all work from the mass center of the pair, I set no time limit; those who want to stay will have to make their peace with those who want to get on to A and the planets. Engineers, let’s get the umbrella out. Mr. Sforza, report if we can’t conform to the restrictions I’ve set. Meeting adjourned.”
The “umbrella” was a thin sheet of highly reflective, highly conducting alloy which could be mounted on the bow of the Manzara, giving her rather the appearance of a fat-stemmed mushroom. Like the hull itself, it could be cooled by Thompson-effect units whose radiators were ordinary incandescent searchlights, able to send the waste energy in any convenient direction. The whole unit was something of a makeshift, a late addition to the mission plan intended to permit a brief but very close pass by each of the stars being studied. It had to be set up manually, since it had not been included in the ship’s original specifications—and even a fusion powered giant like the Manzara was rationed in the mass she could devote to automatic machinery. Once again, the versatility of the human researcher was being utilized.
