Threshold

  Communications were essentially out on the ship. Given some time, especially here, Hohenheim might be able to cobble together a transceiver that worked, even in this part of Jupiter system. But for what purpose?

  "At least I will be comfortable," he said to himself. Main engineering retained power from the main reactor. Storerooms nearby were still pressurized. Despite the damage, there were supplies here that could keep him alive for a long time—weeks, certainly; perhaps even months.

  That was another ironic taunt of the universe, given that he had only the relatively few hours remaining before . . .

  How had Mr. Buckley put it once, in a conversation at dinner on Ceres? Ah, yes: deceleration through lithobraking. That would be happening to him on Io very soon.

  It was hardly a terrible way to end things, though. There would be none of the lingering horror of radiation sickness, and he had done what he could to restore some of his own honor. A quick flash of light and no pain; there were many worse ways to die.

  Except . . .

  That didn't sit well with the general. He drifted over and looked at the consoles. Damage to the main thrust nozzle and its cooling systems. Self-sealing tanks prevented us from losing all the remaining reaction mass. There was minimal connectivity left even in the most basic health-maintenance systems, but the main engineering computers were able to produce a good estimate of conditions throughout Odin.

  He shook his head dolefully. The situation was worsening by the minute. The spin, the imbalance—each time something broke, it weakened something else. It was quite possible the whole ship might come apart before they reached Io.

  Come apart . . .

  He suddenly had a dim memory of a long-ago conversation with Dr. Castillo, the chief engineer on Odin. It had been after he had first boarded the great vessel and Castillo had been giving him a final internal guided tour. What was it?

  "Severable sections," he said to himself slowly. The Odin was made such that in emergencies some components could be separated from the others. The major concept had included being able to remove symmetrical sections of the hab ring in case one of them was damaged, causing imbalance.

  At the time, he had wondered what the point was, given that the probability of actual collision with a meteor was so low as to be not really worth considering. Now, of course, he understood that the designers had been thinking of . . . far more directed disasters. The ship's main contractor had been the European Space Development Company. From the very beginning, undoubtedly operating under the directions of the chief operations officer, Osterhoudt, the company's top engineers had seen to it that the Odin was far more of a warship than she appeared to be. And then, adding insult to injury, had hidden the fact from the Odin's captain but given it to their hand-picked chief security officer.

  The most extreme variant of "severable" would remove the engineering and mass-beam drive—essentially the entire rear of the ship—from the rest, leaving the forward section of the main body and the hab ring drifting. That made perfect sense for a military vessel. Such a separation would concentrate power, leaving the concealed weaponry and drives operable and getting rid of any excess weight. True, maneuverability would be terrible, given the geometry. But the ESDC's engineers hadn't really had any choice, if they were to keep the hidden design a secret.

  But in this case, the problem of poor maneuverability was irrelevant, since Hohenheim couldn't possibly keep the ship intact anyway.

  The general initiated a search for the triggering systems. With his command overrides, it wasn't hard to find. He couldn't reach many of the hab-section controls, but for his purposes it didn't matter. He was going to use the extreme variant.

  First things first. He checked his chronometer. Munin must long since have left for its rendezvous with destiny, and hopefully survival. It was possible that there were one or two other survivors on board Odin, but Hohenheim had managed no contact. At this point, he had to assume that only the dead remained with him.

  And he had to hurry. Every passing hour brought him closer to Io and made any desperate attempt to evade that hellish globe that much less likely to succeed.

  The lateral thrusters . . . Some still operative. Enough, he hoped. He modeled the current movement of the ship on the main console, thanking whatever gods there were that modern interfaces did not require him to do the calculations. Then he ordered a precisely timed sequence of thrusts.

  Slowly, slowly, he began to feel a sense of turning that was separate from the ship's earlier axial spin. Odin was now spinning, more and more quickly, about her lengthwise center of mass as well as the axial. He could feel a faint pressure toward the wall in that direction, as the Odin now tumbled like a thrown bolo instead of a rifled bullet. It was an end-over-end spin that would normally signify disaster. But the Odin was doomed anyway, and there was a purpose for this tumbling.

  The tumbling sent Io spinning smoothly around the cameras' field of view. Once more he input the model, then incorporated the vectors of their approach to the moon. Taking a deep breath, waiting for the designated conditions . . . Hohenheim ordered, "Separate."

  The concussion of separation would have knocked Hohenheim off his feet if he had not strapped in; as it was, his head slammed painfully into the back of his helmet. There were other distant sounds and vibrations that did not bode well for even the section of Odin he had kept with him. But he did not care about that; what was important was whether his desperate maneuver had worked.

  Spinning on approach, when the two pieces separated they retained the same total momentum. Their center of mass would remain in the same place, barring some form of acceleration placed on one component separate from the other. But the center of mass was merely a geometrical and physical construct, one that now occupied empty space. The shattered hab ring and most of the main body hurtled off in one direction, while the engine and drive section spun off in the opposite direction—away from the meeting with Io.

  By itself, that would not be enough; Hohenheim had known that before he started. But he needed all the help he could get; at least it started him edging away from direct central impact with the deadly moon, and drastically reduced the mass of his part of the ship.

  Now . . .

  First the spin had to be brought back under control. The laterals left on this section would be driven past normal design limits, but—again—he didn't need to worry about long-term endurance. No, his main worry was something else entirely, the major remaining question mark in this enterprise, one that might render everything he was doing futile. But it was better to die trying than not to try at all.

  Finally, Odin—what remained of her, rather—was no longer tumbling or spinning. She sat with her mass-drives pointed almost directly away from Io, the blunt-nosed engineering section almost facing toward the pockmarked moon. Almost, but not quite.

  And now, the moment of truth.

  For there really was no other choice. Mangled though the nozzle was, the NERVA-based drive was still operative. It might work for a second, or ten seconds, or longer. It might, possibly, have some failure mode that would blow the control room into shrapnel. But if it worked—even for just a few moments—it just might give him enough thrust to send them plunging around Io instead of into it, hurtling out into the Jupiter system, probably to never encounter another solid object again for years or even centuries.

  He would not get home. But the maneuver might give him the time he needed to report home, and to make his peace with family and friends left behind, before he died. He would die on his terms.

  He checked the vectors one last time. The nozzle control systems were . . . shot. He would have to hope that the imbalance from the missing section of number four driver rib would not be too significant for the time the main drive fired. He offered a silent prayer. Let me not have entirely wasted my last few hours in this world.

  Then he activated the drive.

  For its last time, Odin came fully alive, the thunder of the NERVA rocket delivering a m
illion pounds of thrust, shoving the now greatly lightened vessel forward. Amber telltales lit, then shifted to red, and he could see the drive nozzle starting to come apart. He overrode automated shutdowns. Run until you can run no more, or until you reach the limit of reaction mass I have allotted.

  The power of the rocket vibrated through Hohenheim's bones, a defiant cry of the wounded ship against the approaching destroyer, and he brought his head up proudly. The great ship, the largest ever built by the human race, had done well. One last effort, one final task, and Odin could rest. The ship had been done a great disservice, but it would still give its best to save the last living human being aboard.

  And then, with a doomsday roar that echoed throughout the wrecked vessel, the main engine's nozzle blew entirely off.

  Chapter 43

  "The best hope we have is that someone figures out a way to come get us. And is willing to spend the hundreds of millions to do it," Joe said gloomily.

  "That bad?" Helen asked.

  "It's not good, that's for sure. We were cramped for equipment space, you know that. Our lander has a little reactor on it, but nothing like what we'd need to run the drive. Jackie and I think we can rig it to provide us with power to live on, but that's about it. I can do some slow maneuvering if we have to with the few ion jets we've got, but those do use reaction mass and power, so we sure ain't going home on them. We can't deploy the sail, and we can't refuel the engine, and even if we could refill the reaction mass tanks, without the reactor we couldn't use it."

  "It's ironic," Helen said after a few silent moments on the bridge of Nebula Storm.

  "How so?" asked A.J.

  "Well, usually in the lost-in-space kind of stories, the real problem is either not knowing where you are, or running out of air or food or water. But we've got close to two years of all of that, if we manage to keep power going at all. And we know exactly where we are and where we want to go."

  Jackie, Helen noticed, was still silent. She'd been waiting quietly at the console ever since Horst had been cut off by a burst of static that A.J. had localized to somewhere onboard Odin—a deliberate jamming transmission. That implied that Fitzgerald had caught up with them. No one knew what to say to Jackie. Knowing that Madeline Fathom saw Fitzgerald as someone dangerous, and knowing what Maddie was capable of, no one wanted to raise false hopes.

  The screen suddenly lit up with a transmission. "Nebula Storm, Nebula Storm, this is Munin. Please answer."

  Jackie, of course, answered first. "Horst! Is . . . are you all right?"

  The German's voice was solemn. "I am all right, and so is Anthony. We have six other members of Odin's crew on board. The general asked me to pass on his apologies to you all."

  "General Hohenheim is alive?"

  "He was when we left. At his orders."

  A.J. closed his eyes. "Oh, Jesus."

  "What about Fitzgerald?" Madeline asked.

  "The general stayed to deal with him, Madeline. There is no other way off the ship."

  Maddie nodded slowly. "I see. I hope . . . that you have considerable supplies on board?"

  "We have better than that." Anthony LaPointe's face was actually smiling, a startling contrast from the last few conversations. "I think that I have a way for us to all go home."

  "What?" Everyone, even Horst, seemed surprised. "Why did you not tell me, if that is true?" he asked.

  "Because until we were able to see whether our friends were still alive, there would have been no point. We will need both of our ships and talents."

  "All right," Larry said. "What's your idea?"

  "Our orbits, they are not terribly different. We can match with you, I think you will agree, by doing an Oberth around Io at the right time."

  "If you put yourselves on the right non-collision course first . . . sure."

  "Do you still have any reaction mass on board?"

  "Yes," Jackie answered. "In a pinch we've got actually quite a few tons of water to spare, too. So, what do we do?"

  "It will be risky."

  Helen laughed. "Right now we're all marooned and likely to die really slowly in the end. Screw the risk. What are we going to do?"

  Anthony grinned. "We are all going to land on Europa, my friends."

  "Wait a minute," Jackie said. "Nebula Storm isn't equipped to land anywhere, and even if we were, we haven't got an engine to do the landing with."

  "That is why you need us. We have the engine. Munin was designed to be a SSTO capable of reaching low Earth orbit. We will need to use about two kilometers per second total in shifting our orbit to match up with yours en route to Europa. If we refuel from Nebula Storm—'top off the tanks,' as they say—we will have more than enough to counter the remaining one or two KPS differential with respect to Europa and land. Remember, Munin is more than half as big as Nebula Storm."

  Jackie and Joe looked at each other. "That's going to take some tricky flying," Joe said finally. "And we'll have to make connections that'll take the strain. And . . . Jesus, I dunno. We sure can't do VTOL in this, and we haven't got landing gear. And keeping it balanced . . ."

  Maddie nodded. "It's going to be hellish. But it probably is our only chance. Europa isn't like Io. It's frozen, but a lot of water ice—which we can use for fuel—relatively smooth, and no volcanoes or other immediate threats. If we can set down and live through it, we can fix Nebula Storm, right?"

  Jackie frowned. "Probably. And we'll have the Munin for a reactor, too, if it turns out that we can't get ours running again—which we may not."

  "And once you are running again," Horst said, "your Nebula Drive can be used—with the right kind of sailing—to get us heading home, yes?"

  "Yes, indeed," said A.J., sliding an arm around Helen's waist and hugging her in relief. "Yes, we can."

  "Then let's start designing," Jackie said. "Is Mia there?"

  "Yes, she is one of the survivors."

  "Good. Because we're all going to have to work on this, and when we finally match up, we'll only have a few hours to figure out how to lock our ships together well enough to take the stress of landing. At least it's not in an Earth gravity well, but it's still going to be a hell of a ride . . . and a lot of stress on any link we make." She started bringing up the plans of the Nebula Storm and prepping them to send to Munin.

  Helen took A.J.'s hand and pulled him up.

  He looked startled. "What? I have to—"

  "Get some rest, that's what you need to do. They won't need your super-sensor skills for the planning. They'll need them when we get to the installation and when we do the landing. So we're going to go get food for everyone, have a dinner, try to relax, and then get some sleep."

  "An excellent idea," Madeline confirmed. "I will be doing the same thing in a little while. Because I think I'm going to end up the pilot on our side."

  "And aside from a few calculations, we won't be needed until docking, either, Tony," Larry pointed out. "Sorry, guys, but you engineers work out the details. We'll be getting up in time to do the work."

  "And try," Madeline confirmed, "to get some rest yourselves, if you can. We will probably all want to be wide awake when we get to the landing."

  "Yes," agreed Horst. "We will be busier than you, though. First we have to make burn to pass Io—which will be in a few minutes—and then Oberth as we reach it."

  "Good luck on that, then."

  Helen waved at the screen. Then the two of them made their way to the galley. "You don't even sound scared," A.J. said.

  She turned and pressed into him. "I'm terrified, A.J. But there's nothing a xenopaleobiologist—whatever I am—can do. If anyone can get us out of this, it's the people on this ship. And then I just have to not make you, or anyone else, worry. It's bad enough—I don't need to make it worse."

  His hands held her tightly. One moved up and stroked her hair. "I won't let you die."

  "I hope not. I married you for the miracles." He laughed softly and hugged her even tighter. Finally she let go and turned. "N
ow, let's get out the Joe Dinners. If this does have a chance to be my last meal, it'll damn well be a good one."

  Chapter 44

  Eventually, Fitzgerald thought to check the time. Then he checked his radiation meter.

  He'd died fifteen or twenty minutes earlier. Perhaps half a hour, depending on his body's resistance to radiation. But whatever the specific moment it had happened, his life had ended. Even if, by some miracle, a spacecraft arrived to rescue him now—it would have to be the Munin, perhaps because Eberhart had been overcome by unlikely mercy—it wouldn't matter in the least. No doctor, no hospital, not even on Earth, could have saved him after this much radiation poisoning.

  But dignity mattered. It always mattered. Richard Fitzgerald had been slain by Jupiter himself, had he not? No one since the time of Homer could make that claim.

  He stopped gazing upon his murderer and looked ahead, toward Io. The huge moon was clearly visible now, clothed in its bright and fatal colors.

  So, as it turned out, there was still one last hope left. Perhaps Richard could last long enough to die on one of the solar system's true hell planets, after being struck down by the lord of the gods. Wouldn't that be something to boast about, if there turned out to be an afterlife? Richard didn't think there was, but . . . you never knew.

  It was not to be. When he felt the first twinges of nausea, some time later, he reached to his belt and took out a gun. It looked like one of Vanna's, so he made sure it unlocked to his key code.

  Dignity mattered. It always mattered. Richard Fitzgerald was not going to go out suffocating on his own vomit in a spacesuit. He took one last look at Jupiter and fixed his eyes on Io. The moon was close enough now to see the details of its surface—which consisted mostly of volcanoes, it seemed.

  He pressed the gun to his faceplate, centering the barrel between his eyes as best he could. Then, looking straight onto the face of hell, pulled the trigger.