Page 19 of Threshold


  "It's huge," Helen murmured.

  "Well," Joe answered from the other side of the ship, "partly that's because you're up so close and it's inside. Compared to Nobel or Nike, it's pretty tiny; mass of the hull and interior bracing and assorted structural elements is about a hundred and ten tons or so."

  Helen blinked; to her, the almost-living, streamlined shape seemed colossal, at least the size of Nike. But she knew that Nike, even empty, massed around two thousand tons.

  "That's a little deceptive, though," A.J. said. "That Vault material is tougher than anything else we've ever seen, and that made it possible for them to make this thing bigger than it might be otherwise. This little beast measures about sixty-five meters long and is about fifteen meters across at the widest part there. And, like Nike or Nobel, it's got a lot of empty space inside. Which is good, because we're gonna need it all."

  "Really?" Helen studied the ship, which was somewhat more elongated in what she thought was the front, coming to three slender points at the very end; the rear of the vessel flattened out into an almost tripartite tail. Somehow it reminded her of a cuttlefish or squid in swimming posture. "There's only six of us going. And you're vandalizing the thing to make more room, it looks like."

  The "vandalism" Helen pointed to was the addition, at the four cardinal points around the vessel's girth, of long backswept rods ending in slightly curved blocks. The four jarring additions, clearly human-built, were attached just behind the circle of bamboo-shoot–shaped spikes.

  "I'll admit they're aesthetically displeasing on this ship," Jackie Secord said, entering the conversation as she exited one of the ship's locks. "However, those four habitat modules will—once we get her outside—extend out and allow us to spin up for gravity, just like Nobel, and we'll definitely need that to stay healthy on the way."

  "And," Joe said, "we will need every bit of space we can get. We can't get nearly as good recycling gear set up for this ship as we could for the ships we had years to design, so we have to take a lot more consumables. Normally we can make do with slightly less than two tons of consumables per person per year, but with the systems we're dealing with . . . Well, I think we'd probably be able to get away with three or four, but I'm going with six, and figuring on at least a three-year trip. So that's nearly a hundred and ten tons of consumables—food, water, and air. To run the ship needs power—lots of it—which is why we're taking the base reactor. That's about seventy tons right there. Add in twenty tons of lander and various equipment, and we're around three hundred tons main payload. And then we need seven hundred tons of fuel capacity."

  "Fuel?" Helen was puzzled. "I thought the point of this dusty-plasma sail was that it didn't need fuel. Well, a few hundred kilograms of dust and gas, but not fuel."

  "True," Joe said, "But to do fast course changes—or to change direction 'against the wind,' so to speak—you need a rocket, or something like it. We may need to do an Oberth around Jupiter, and when we want to come back, we'll definitely want to use that approach to head back in-system."

  "You're talking about a NERVA-style drive, like the Nobel, right?"

  Jackie nodded. "Exactly. We're saying 'fuel,' but really it's just reaction mass. Heat it up with the reactor, throw it out the back."

  Helen frowned. "But . . . if I remember right, the base reactor's rated at something like thirty or fifty megawatts. I'm sure that Nobel's engine reactor is a lot more powerful, maybe ten or twenty times more powerful. Is the base reactor going to be enough, Jackie?"

  The dark-haired engineer grinned. "No and yes. If I had to use the reactor straight, no, I could redline it and still only get a pretty puny rocket. I want something close to the real deal. What I can do is basically create the equivalent of a fast-surge accumulator—a big bank of superconducting batteries that gather up a few hours of the reactor's output and then release it in a relatively few seconds. For those few seconds I can essentially pretend I've got Nobel's reactor driving this rocket instead of our base reactor. And I really do have to be able to push the rocket to basically the same level of performance that it would have for Nobel, because I'm going to need to do a real fast burn as we pass Jupiter, if we end up intercepting Odin, or as we pass Saturn, if we just try to beat them to the punch."

  "You can't do it over a longer stretch?"

  "Nope. The whole point of the Oberth maneuver is timing. At perihelion you do the delta-vee burn, and depending on whether you do it to speed up or slow down, you either speed up or slow down a lot more than you would otherwise. Basically you're either gaining or losing the energy equivalent to throwing your fuel down the gravity well you're maneuvering in. It's a squared function, so even a relatively small delta-vee will get you a pretty big change."

  She pointed to a huge funnel shape just visible past the flattened fins of the aft portion of the vessel. Helen recognized it as one of the spare NERVA rocket nozzles for Nobel. Meters across, the spare nozzle had been jury-rigged to the rear of the alien vessel. "And that will handle the load just fine."

  "If," Joe noted, now inside the ship, "our calculations are all correct. If that thing's significantly off from the center of mass when we fire, we could be in trouble."

  "That's why we've done the calculations and designs six times, Joe. But we can't wait much longer. Even with all the tricks we can pull off, A.J. doesn't give us more than another six days before there's no way to catch them at Jupiter, and not all that much longer before we would just have to give it up entirely."

  "I know. Just pointing it out. I've crashed before, you know. Twice. I'd rather not do it again, this time almost four hundred million miles from help."

  "You can't launch from inside Ceres, though. Not without using your fuel, right?" That was A.J.'s voice; he was working on the control systems deeper in the vessel.

  "We will use some of the fuel that way. I want to test her before I go out that far. Do I look crazy?" Jackie said. "I want to fire the engine long enough to get into orbit around Ceres. Feynman or Einstein will refuel us—I'm using mostly water, which isn't the best fuel for a NERVA rocket by a long shot, but it's stable, easy to get here, and useful for a lot of other things—and then, if everything looks good, we'll take off. If the dusty-plasma drive doesn't work, well, then we go to plan B. That's B as in blackmail."

  "I could settle for that, if I have to. But I am confident she'll fly," A.J. said. "And we need to think about publicity here. Dusty-plasma drive doesn't sound sexy."

  "What would you suggest?"

  He told them. "But I'm waiting until I see it running. I think that you'll agree I'm right, and if so, we've also got the name for our ship."

  Jackie nodded. "Provisionally accepted. We'll see when she launches. How about the gas and dust supply for the sail itself?"

  "Got it. I'd thought of this wrinkle earlier, but the fact that our friends on Odin were actually using it kicked me into getting it set up. We'll be using Faerie Dust for a lot of it. That will give us quite a bit of control over the sail, even more than the Bemmie magnetics. Of course, Bemmie probably used that, too, given that they were even using nanotech for their notepads, but there's no way for me to tell. We'll be able to vary the reflectivity and the geometry to some extent. Much more maneuverable than the base version. So I can say with some confidence that I'll be able to put you on any course you want pretty reasonably quick. We can make our final decisions once we see how she performs."

  Jackie nodded. "Thanks, A.J. I really didn't want to be locked into one course from the start."

  "It wasn't likely, but now it's not a problem. If she works at all. Which I hasten to add she will, Captain."

  Helen saw Jackie wince at the title of address. As the engineer for the drive and the one most familiar with the operation of an actual vessel in deep space, Jackie had ended up with the two "hats" of captain and engineer. Madeline Fathom was willing to be an emergency pilot of sorts, but she refused to take command.

  "On the ground, or in combat itself, perhaps," she'd s
aid. "But you're going to be the one in charge in space, Jackie. A.J. isn't suited to it, and neither is Joe, while neither Helen nor Larry is qualified. Larry can help with the navigation and investigation of anything in the astronomical arena, but he's got minimal technical knowledge. As we can't really take any more people, that leaves us with no other choices."

  "Come on, Jackie," she said. "It's not that bad."

  Jackie shrugged and then gave an unwilling half smile. "Well, yeah, I guess. If by a miracle this eons-old alien vessel does rise from the dead, I'll be the commanding officer of the fastest ship ever built." The smile widened. "And then I get to prove it by catching the other fastest ship ever built."

  Helen saw the smile widen even more, becoming somehow sharper, and it wasn't a nice smile at all. But then, she'd feel the same in Jackie's position. She almost felt sorry for Horst and Odin.

  Almost.

  Chapter 28

  "All clear?"

  "All clear, mates," Bruce's voice responded from Feynman. "Got clear images comin' in from all the Beholders in range, too. Includin' the one you put on the long orbit, A.J."

  "Thanks, Bruce. I think we'll appreciate the long view if this thing works."

  "All right, Bruce," Jackie said, voice somewhat tense. "We're in orbit around Ceres right now at an average altitude of fifteen hundred kilometers. I'm going to have Joe and A.J. try to kick in the drive as we start coming around in the direction away from the sun. If it works, we'll be able to accelerate for about half of each orbit and break free into the outer system pretty fast. A few orbits will do it. If it doesn't work, no major problem. Eventually, we'll have Feynman drag us back in."

  "Right, just as planned. How are the control systems looking? You got out all right, but is the geometry set?"

  "Very good, actually. We can keep even this much water liquid with the waste heat from the reactor and the insulation we already have, and that allows us to use the water as a sort of balancing agent. We can move it around in response to minor changes of the center of mass during acceleration. Lots of calculations involved, but the design models seem to be working out."

  "Good. So, how's your feeling on running her dry out near Jupiter or Saturn, then?"

  Jackie gave a strained laugh. "Not totally relaxed about it, but I feel a lot better than I did. All the other systems are working well. We do have auxiliary radiation shielding set up just in case, but Larry and Joe assure me the dusty-plasma drive should shield us pretty well. We've got all the food you could spare, entertainment stuff to keep us from getting bored, and all the equipment we could squeeze out of the research staff. According to Madeline, Nicholas has promised that he'll get Nike out here with another reactor as soon as possible, no matter how many favors he has to call in, assuming this thing works."

  A blinking light showed at the edge of her vision. "A.J.'s just signaled. Coming up on sail deployment."

  The screen showed a view of the long, tri-ridged alien vessel, tentacular sail-control vanes extending from the midline, four Earth-designed habitat modules on long booms just aft of them, with the bulky Earth-built fuel tank and NERVA rocket nozzle easily visible at the rear. The clash of engineering styles was jarring; the Bemmius preference for almost organic-appearing curves versus the squarish, sharp-edged Earthly add-ons. The interior was in some ways worse, she mused, watching the control vanes continue to reach out. The main supports and parts of the hull remained, but much of the rest had been replaced, chopped, modified; you could still see the lower Bemmie-style designs in some areas, where others clearly were high-headroom designs forced into the space of one and a half or two Bemmie rooms. The resulting vessel might be spaceworthy, but she suspected that neither human nor Bemmius passengers would be entirely comfortable in the setting.

  Enough musing. "All right, A.J. Set sail!"

  "Deploying dusty-plasma sail, aye, Captain," A.J. said, perfectly seriously. "Main magnetic field now generated. Releasing gas now."

  Jackie thought she saw a faint shimmer in the areas of the release nozzles, but that might just have been imagination. The status graphics in the upper right, however, showed the sudden expansion of the magnetic field, ballooning outward at incredible speed. "Field inflation confirmed. Releasing Faerie Dust."

  Now she was sure she saw something. And wasn't the view of the stars around them a little . . . dimmer? A tiny bit washed out, almost fogged?

  "Ionization of plasma confirmed. Energy consumption within calculated limits. Everything holding, Joe?"

  "We're doing fine. Field's just about expanded to maximum." The professional tone disappeared for a moment. "Just look at that, will you?"

  The long-range images, taken from a Beholder nearly five thousand kilometers away, showed what short range simply could not. The vast tenuous sail was nearly invisible to those within it, as a mist or light fog may only slightly dim the light and soften edges to those viewing it from within.

  To the Beholder's view, projected on the screens of the alien vessel, Feynman, and Ceres base, the tiny dot that was the actual ship suddenly seemed to radiate a mist, a mist that expanded outward vastly, covering more than eleven degrees of the sky, looming up like a pearlescent stormcloud. The mist shimmered, and as more light and energy impinged upon it and the Faerie Dust dispersed within, delicate hints of color and interplay of light glowed out, became a spectral shadow occulting the entirety of the immense asteroid Ceres itself.

  "Magnetosail? Dusty-plasma? Bah." A.J.'s voice held a combination of awe and triumph. "We are riding one of the living forces of creation, a miniature version of the cradle of stars. Captain, ladies and gentlemen, I give you the legacy of Bemmius secordii to their namesake Captain Jacqueline Marie Secord. I give you . . . the nebula drive."

  Jackie found her voice a moment later. "You were totally correct, A.J., and I'm glad. Joe, is the champagne ready?"

  "Rigged for breaking!"

  A.J. continued, overdramatic lines being his specialty, and in this case, somehow appropriate. "We're giving chase to the King of the Gods, in a ship drawn by a cloud lit by the power of the sun and of the thunderbolt."

  Jackie nodded. "And so we christen thee—the Nebula Storm!"

  A faint additional sparkle of glass and mist was visible from the bow of the vessel. "Dramatic, but I like it," Bruce said. "Is the sail actually working?"

  "If you can see it, it's working. We're getting several percent reflection. Acceleration is . . . about half a percent of gravity. We'll reach Ceres escape velocity by the end of this orbit, I think, and then it's outward bound." A.J. turned from his seat to look at Madeline, who had been quietly watching the launch. "Maddie, you can send the go-ahead. We're on our way to Jupiter, and we are going to catch Odin just about the time they get there." He grinned over at Jackie. "And wouldn't I just love to see their faces whenever they finally look over their shoulders and see what's coming after them!"

  * * *

  Horst sat impatiently in front of the screen. It had taken some time to work around the idiotic communications blackout that Fitzgerald had seen fit to impose. Had it been the general's direct order, Horst might have felt more inclined to either obey, or at least to make a polite inquiry as to exactly why they weren't supposed to communicate directly with other organizations. As it was, though, Fitzgerald had been such a scheisskopf—as Horst's grandmother would have called him—that Horst took a positive pleasure in ignoring him. Especially since he had promised Jackie that he'd send her a message every day after they left, and the blackout was making him break his word.

  Having managed to finally send a message back to Jackie at Ceres, he was now waiting for the response. Nervously waiting. Their relationship when he left had been at that twitchy stage where nothing was entirely clear. At this range, assuming she replied pretty promptly, round-trip would still be less than ten minutes. But it had been more than thirteen days, and if the people still on Ceres had guessed what was going on, Jackie could have more than one reason to be angry at him.

/>   He was pretty sure she'd eventually understand. After all, taking the information didn't hurt anyone directly, and she must have guessed what he was supposed to do for the E.U. He'd even—sort of—told them. His best bet, he guessed, was to just admit that what they did was a sleazy trick and throw himself on her mercy. If they'd guessed. No point in borrowing trouble.

  Of course, that didn't sit well with him, anyway. Sneaking around wasn't his idea of the way you were supposed to behave, especially to friends. Which was another reason why he didn't like Fitzgerald and his cronies. Odd, too, that there were other areas of the system he'd run into that seemed to have security on them he didn't remember installing. He might have to look into that himself. Well, no, he should probably ask the general.

  What was taking her so long? She should be off-shift but not asleep now. He noodled around with some of the data he had on the secure areas. Some looked like they had to do with the engine controls, which made no sense at all. He'd done all of that, and there wasn't any need for more security on them. But it was there, nonetheless.

  The screen suddenly flickered, and he leaned forward eagerly. Then sat back in startlement as the face of Bruce Irwin appeared, looking none too friendly,

  When he spoke, his Australian accent was thicker than usual. "Mr. Eberhart! So sorry to be the one respondin', but Jackie isn't here. I'm not sure that she'd even want to be speakin' to you, but you might try just waitin' a bit. She'll be catchin' up to you lot around Jupiter way." The transmission cut off as abruptly as it had begun, leaving Horst staring at the blank screen in total confusion.