Who could have believed that flying close by Jupiter was harder even than approaching the sun, and yet it was true, and yet we made it, and as Jupiter, for all its great size, was only 1 percent of the sun's mass, we were quickly out of the hideous crackling roar and on our way out to Saturn, and as our senses cleared and ability to hear and perceive our own calculations returned, we were happy to find that we were on precisely the trajectory we had hoped to be. Five g's of force had been exerted on us during the few minutes of the pass-by.

Two down, three to go!

Ah, but five more hibernauts died in that pass. Dewi, Ilstir, Mokee, Phil, and Tshering. Nothing to be done about it, we were doing the necessary, as Badim would have put it, but such a shame. We knew and enjoyed those people. Had to hope they were not engaged in a dream at the time, a dream suddenly turned black: sledgehammer from the sky, an immense roaring headache, the black noise of the end come too soon. So sorry; so sorry.

Nevertheless, it was imperative to collect oneself and prepare for Saturn, there on a long beam reach, and despite the really useful and heartening decelerations achieved so far, it was still soon to come, only sixty-five days to prepare, and as we were coming in on the plane of the ecliptic, it was going to be important to miss the famous rings, which luckily are in Saturn's equatorial plane, which is offset to Sol's equatorial plane by several degrees, meaning we did not have to do anything but be sure to make a very tight pass of this gorgeous jewel of the system, which was our intention anyway. We were only going to turn a few degrees, and so would duck inside the innermost ring and be on our way.

And indeed, as we approached the ringed planet and the little civilization of settlements on Titan and many other moons, the civilization that had in fact built us and sent us on our way almost four centuries earlier, and also had reactivated the laser lens that had slowed us down enough to try our maneuvers now, it was a pleasure to say hello, even in passing. It was also a pleasure, not just to hear the various welcomes from the Saturnians, but also to hear nothing from the planet itself, for unlike Jupiter, Saturn has a very low amount of internal radiation. Indeed it was a quiet and cool pass-by, compared to the previous two, and the main feature of interest was the quick view of the rings, so immensely broad in reach while at the same time so thin in cross section, a great gift of gossamer gravitation, much less thick than a sheet of paper by proportionate comparison, indeed if it were reduced to a round sheet of paper in size, it would have been mere molecules thick. A natural wonder of circularities, like a physics experiment or demonstration, nicely displayed to us as we passed. And given its smaller mass, our slower speed, its coolness, and the smoothness of its upper atmosphere during our aerobraking, this was by far the calmest pass yet, maximum g-forces just 1 g, and an easy slight turn for the next leg out to Uranus. At this point we were only going 120 kilometers a second. Still fast in local terms, it was also true that we had a bit more time before our next pass would occur, which was to say ninety-six days. And no human or animal died.

On the way out to Uranus, we tried to come to grips by way of modeling with the fact that our pass-by of that lightly banded and ringed giant was going to be different, because it rotates transversely to the plane of the ecliptic; its axis of rotation is such that it rolls around the sun like a ball, a strange anomaly in the solar system, an anomaly the cause of which a cursory inspection of the literature suggested was still poorly understood. What it meant now for us was that if we did the usual aerobraking, which indeed we had to do, as it was necessary for our continuing effort at deceleration, we would be punching through several of the planet's latitudinal bands, created by winds each rushing in the opposite direction to those above and below it, as on Jupiter; and so at each border between bands there would be a similar area of wind shear and atmospheric turbulence, well represented by the wild band borders of great Jupiter. Perhaps not a good idea!

We had a bit more time than before to model this problem, although we still looked quite fast to the people of the solar system, who were used to these crossings taking years. Although there was also a class of very fast ferries that could jaunt around the system, if they found they had a really pressing need for speed. Fuel and other costs made these quick trips very rare, and yet it did give the locals a basis for comparison, which is why we had been such a marvel at first, coming in faster than anything. Now we were normalized in terms of their idea of speed, fast but not extraordinarily so. It might also have been true that the novelty of our return was also wearing off, and we were becoming just another odd feature of life in the solar system. We hoped so.

Soon enough Uranus approached, its narrow faint ring making it clear that we were going to round it pole to pole, and though the ring was no problem to dodge, nor the little fragment moons, the models had confirmed that we needed to be very cautious with our aerobraking, staying as high in the Uranian atmosphere as we could while still coming out of the turn headed toward Neptune, after a sharp right curve.

So in we came, and Uranus grew in the now-familiar way, looking mauve and lavender and mother-of-pearl, and we hit the upper atmosphere and at first it was the same as always, a sharp deceleration, ramping up to 1 g, not at all bad, and then WHAM WHAM WHAM WHAM, it was as if we were running through doorways without opening the doors, terrific smacks that increased in shuddering with each impact. Things broke, animals and people died, probably of heart attacks, six people this time, Arn, Arip, Judy, Oola, Rose, and Tomas, and it really was becoming unclear whether we could sustain many more such concussive slaps, it was startling how much a wind shear wall could obstruct one, a little left-right punch followed instantly by a right-left punch, when happily we were out of the atmosphere again before anything more damaging occurred, and were again on course, and on our way out to Neptune.

Which meant we were coming to the crux. Push had come to shove. Again we would come in, dodge the negligible rings, make a dip into the upper atmosphere of this cool blue beauty, reminiscent in appearance to Tau Ceti's Planet F, we found. But this time our turn had to be almost a U-turn (perhaps the source of the use of the letter U in the gravity assist equations?), not quite a true U-turn, but 151 degrees, quite a wraparound, a V-turn, not easy at all, and at 113 kilometers a second. That meant a deeper dive into the atmosphere, and more tidal forces, and more g-forces. Aerobraking would again shake us; it would feel like we were a rat in the jaws of a terrier, perhaps. But if we succeeded, then we would be headed back in, downsystem toward the sun again, quite considerably slowed down, and in a pattern that would seem to allow us to continue our decelerative cat's cradle, pinballing around the solar system from gravity handle to gravity handle, at least for as long as our fuel held out to make course corrections. We were running low on fuel.

So: Neptune. Cool blue-green, lots of water ice and methane. Gossamer ring, barely visible. Not much sunlight out here. Well beyond the habitable zone of any life-form known. A slow place. Interesting to have given it a submarine name; it seemed somehow appropriate, in the usual mushy metaphorical way, in that impressionistic, vague, feeling kind of way.

We were still going very fast, but it was a long way to go, so we had 459 days to set things up. The diameter of our approach window was smaller than ever, given the need for such a sharp turn; vanishingly small; really hitting the mark precisely on the nose of our capture plate would be best, so we were setting the trajectory window at a hundred meters in diameter, which after all the distance crossed was rather extraordinary to consider: but even so, a hundred meters was a bit too big a window; really a single meter, a geometrical point, would be best.

In we came. Hit the mark. Started the pass, knuckles white.

Aerobraking comparatively smooth, compared to the hammering of Uranus. A rapid vibration, an occluding of vision in the upper clouds, a few minutes of blind trembling, of intense anxiety, nail-biting suspense; and out again, after another 1-g press, which this time was more than ever a matter of tidal forces, as we swung around so far. V-turn!

And out of the pass, headed toward the sun. Downsystem. Looped in. Caught. Back.

If each of our five passes was called a one-in-a-million throw, which was a very conservative estimate of the odds, then all five together made it a one-in-an-octillion chance. Amazing-literally-in that we had indeed been threading a maze. Little joke there.

And so down to the sun again, going slower than ever, although still 106 kilometers per second. But the next pass of the sun would put a good heavy brake on that, and on we would go, slower each time, working through a version of Zeno's paradox that fortunately was not truly a perpetual halving, but would come to an endpoint, thus our own happy ending to a very severe halting problem.

On the way back in, we passed near Mars, which was interesting. There were so many stations there that it was no longer a scientific facility only, but something more like Luna, or the Saturnian system, or the Europa-Ganymede-Callisto complex: a kind of nascent confederation of city-states, buried in cliffsides and under domed craters, but each outpost quite various in design and purpose, and altogether more than just an outpost of Earth, though it was still that too. Early dreams of terraforming Mars quickly, and thus having a second Earth to walk around on, had come to grief, mainly because of four physical factors overlooked in the first flush of optimistic plans: the surface of Mars was almost entirely covered by perchlorate salts, a form of chlorine salts that had given Devi fits as well, as only a few parts per billion gave humans terrible thyroid problems, and could not be endured. So that was bad. Of course it was true that many microorganisms could easily handle the perchlorates, and in their eating and excreting consume and alter them to safer substances; but until that happened, the surface was toxic to humans. Worse yet, there turned out to be only a few parts per million of nitrates in the Martian soil and regolith, an odd feature of its original low elemental endowment of nitrogen, the reason for which was still a source of debate, but meanwhile, no nitrates, and thus no nitrogen available for the creation of an atmosphere. And so the terraforming plans were faced with a radical insufficiency. Then third, it was becoming clear that the fines on the Martian surface, having been milled by billions of years of drifting in the winds, were so much finer than dust particles on Earth that it was extremely difficult to keep them out of stations, machines, and human lungs; and they wreaked damage on all three. Again, once microorganisms had carpeted the surface, and fixed the fines by bonding them into layers of desert pavement, and also as the surface got hydrated and the fines became bogged in muds and clays, that problem too would be solved. And last, the lack of a strong magnetic field meant that a thick atmosphere was really needed to intercept radiation from space, before the surface would be very safe for humans to be on.

So, none of these problems were pure stoppers, but they were big slower-downers. Concerning the nitrogen lack, the Martians were negotiating with the Saturnians to import nitrogen from Titan's atmosphere, as it had become clear that Titan, for its own terraforming plans, had too much nitrogen. Transfer of that much nitrogen would be a Titanic chore, ha-ha, but again, not impossible.

The upshot of all this was that the terraforming of Mars was still on the table and a subject of huge enthusiasm for many humans, particularly the Martians, although really, in strict numerical terms, even more of these enthusiasts lived on Earth, which seemed in fact to be home to enthusiasts of all kinds, for any project imaginable, judging by the roar of radio voices coming from it, almost like an articulated version of Jupiter's mighty radioactive yawp. Oh yes, Earth was still the center of all enthusiasm, all madness; the settlements scattered elsewhere in the solar system were outliers. They were expressions of Terrans' will, and vision, and desire.

So, past the bustling little world of Mars, where they lived dedicated to the idea that they would successfully terraform their world in no more than forty thousand years. They seem to regard this as fine. As long as it could be done, it should be done, and would be done; and so the work was good.

The crucial difference here, it seemed to us, between Mars and the terraforming project we had left back on Iris, was that Mars is very near Earth. Its human settlers were constantly going to Earth for what they called their sabbatical, and receiving shipments of Terran goods and materials. And these infusions of Earth meant that they were always escaping the zoo devolution problem. Iris did not have those infusions, and never would; and it was notable (though in fact we had forgotten to note it, in the press of events) that we had not heard anything from the Iris settlers for over twenty-two years. Possibly a very bad sign, although it would benefit from a discussion with Aram and Badim, and the rest of the humans sleeping on board, to interpret more fully what it might mean. But certainly there was one explanation for the silence that was simply very bad.

Then downward to the sun again, down down down, feeling the pull, speeding up, heating up. In for another nail-biting scorcher of a pass, although this time without the ball and chain of the magnetic drag hauling back on us as we went; but it lasted considerably longer, as we were now traveling only 4 percent as fast as we had been going on that first terrifying pass. This time it would take us five and a half days, but we stayed farther out, and only heated up to the same 1,100 degrees on the exterior, and held there; and when we came out of that pass, we were headed for Saturn. No more of mad roaring Jupiter, if we could avoid it, and this round we could. Each leg of the cat's cradle we were making would be different now.

Round and round the system we flew, slower and slower. We had very little fuel left. We were a kind of complicated artificial comet. Our trajectory clarified before us as we went. We passed by many inhabited planetary and asteroidal bodies. For quite a few years, the people in the solar system did not seem to get used to us; we were still a marvel of the age, a sight to be seen, a great anomaly, a visitation, as if from another plane of reality. That was the Tau Ceti effect, the starship effect. We were not meant to come back.

Slower, slower, slower. Each pass a deceleration to be calculated, and the new speed employed in the calculation determining the next pass-by. Always our planned trajectory extended many passes out into the future, although there was a lacuna growing out there, a time when our fuel ran out, or say that it grew too low to be used, as we were saving some little last bit for some last purpose. Because there was a time coming when the arrangement of the planets in their orbits was going to present us with an insoluble problem. Cross that bridge when you come to it; yes, but what if there is no bridge? That was the ongoing question. But for now, as the passes kept passing, each easier to manage, each with a slightly larger target window, it continued to be a problem out there at the edge of the calculable, always beyond the ever-receding horizon of calculable passes. Some of them required more fuel than others, some none at all. The timing was all. As always.

The best possible trajectory was going to take several more years to get down to a workable disembarkation speed. Late in that time, the amount of fuel on board would have shrunk to an amount too small to use. When we ran out of fuel, it would be impossible to adjust our course to the next rendezvous. We might, by way of a good plan and some luck, make two or three more gravity swings by dint of perfectly placed insertions and departures; but then, inevitably, we would miss one, and either shoot out of the solar system in whatever direction we were headed, or collide with some planet or moon, or the sun. At the speed we were traveling for most of this time, a collision with almost any object in the solar system would have had the kinetic energy to wreak great damage. Comments from the locals often pointed this out. It was still being suggested that it might be a good idea to move a spaceship or some fifty-meter asteroid into our trajectory, intercepting us and causing our destruction without anyone else suffering any damage. This was a popular plan in some quarters.

Threats, from the very civilization that had built us and sent up out to Tau Ceti. We let our people sleep on. Nothing to be done about it.

Passages of Saturn stimulated research on our part into this matter of who had built us, and why. A twenty-sixth-century Saturnian project, an expression of their love for Saturn, for the way humans were spreading out away from Earth. Expression of their burgeoning confidence in their ability to live off Earth, and to construct arks that were closed biological life support systems. This from people who were still going back to Earth to spend some time there every decade or so, to fortify their immune systems, it was believed, although the reasons that such sabbaticals conferred health benefits were poorly understood, with theories ranging from hormesis to beneficial bacteria osmosis. Thus their theories concerning their situation in space were not aligned with their actions when it came to sending off a starship, but this kind of discrepancy was not unusual in humans, and got overlooked in their larger enthusiasm for the project.

Another obvious motivator for constructing us was to create a new expression of the technological sublime. That a starship could be built, that it could be propelled by laser beams, that humanity could reach the stars; this idea appeared to have been an intoxicant, to people around Saturn and on Earth in particular. Other settlements in the solar system were occupied with their own local projects, but Saturn was the outermost edge of civilization, Uranus and Neptune being so remote and without usable g; and the Saturnians were very wealthy, because of Titan's excess nitrogen and the desire many Terrans had to go to Saturn and see the rings. The Saturnians of that time therefore had the will, the vision, the desire, the resources, the technology; and if that last was sketchy, they didn't let that stop them. They wanted to go badly enough to overlook the problems inherent in the plan. Surely people would be ingenious enough to solve the problems encountered en route, surely life would win out; and living around another star would be a kind of transcendence, a transcendence contained within history. Human transcendence; even a feeling of species immortality. Earth as humanity's cradle, etc. When the time came, they had over twenty million applicants for the two thousand spots. Getting chosen was a huge life success, a religious experience.

Human beings live in ideas. That they were condemning their descendants to death and extinction did not occur to them, or if it did they repressed the thought, ignored it, and forged on anyway. They did not care as much about their descendants as they did about their ideas, their enthusiasms.

Is this narcissism? Solipsism? Idiocy (from the Greek word idios, for self)? Would Turing acknowledge it as a proof of human behavior?

Well, perhaps. They drove Turing to suicide too.

No. No. It was not well done. Not unusual in that regard, but nevertheless, not well done. Much as we might regret to say so, the people who designed and built us, and the first generation of our occupants, and presumably the twenty million applicants who so wanted to get in our doors, who beat down the doors in fruitless attempts to join us, were fools. Criminally negligent narcissists, child endangerers, child abusers, religious maniacs, and kleptoparasites, meaning they stole from their own descendants. These things happen.

And yet, here we were, with 641 people brought back home, and if things worked out, at the end of the endgame, a good result might still be possible.

Round and round and round we go, And where we stop, nobody knows.

Maypole weaving to celebrate the spring. Ribbons danced into a woven pattern judged pleasing to the eye. The pole a symbol of the axis mundi, the world tree. We danced that dance.

The fuel problem became serious enough that we began to angle farther into the upper atmospheres of Neptune and Saturn with some catchment containers open, which both increased the deceleration of these passes and gathered Saturnian and Neptunian gases. Then we filtered out the helium 3 and deuterium captured in the containers. We even began to collect methane, carbon dioxide, and ammonia, all present in much greater quantities, to serve as propellants of lesser explosive power. At a certain point, approaching as inexorably as all other processes in time, anything was going to be better than nothing.

As always with aerobraking, it was necessary to strike the upper atmospheres at an extremely particular angle, not so shallow as to skip off, but not so steep as to dive in and burn up. Stresses to the ship were severe even on the best atmosphere dives, but with catchment containers opened, the shuddering was worse than usual. The local inhabitants of stations nearby observed these pass-bys with intense interest. There were still calls to "shoot the damn thing out of the sky," to "stop these cowards from endangering the civilization they have let down so badly," but most of the whiners were located on Earth, and a cursory examination of the input revealed that these people were always going to quickly move on to complaints about something else. It was a whiny culture, we were finding. Actually, the longer we pinballed around the solar system, the more we wondered if our people were going to be all that happy to be back. Say what you will about the doomed little settlement on Iris, no one there was going to be so short of things to do that they would be spending time complaining to the world about this or that. In any case, in our situation it was very unlikely anyone would ever act on these hostile sentiments, not that there was much they could do. But it did seem preferable to avoid actively antagonizing anyone on the inhabited planets and moons, and so we included that parameter in our trajectory algorithms.

Trajectorizing. Really a very computationally heavy activity. Recursive algorithms were allowing us to get better at it, however. The always moving Lagrange points, and the strange fields these and other anomalies produced; the riptides, crosscurrents, and all the ways that gravity surged and flowed in its mysterious invisible fields; these were becoming better and better known to us.

Sol, Saturn, Uranus, Mars, Saturn, Uranus, Neptune, Jupiter, Saturn, Mars, Earth, Mercury, Saturn, Uranus, Callisto...

The universal variable formulation is a good method for solving the two-body Kepler problem, which locates a body in an elliptical orbit at various points in time. Barker's equation solves for location in a parabolic orbit, very frequently applied given our trajectories, which often consist of a radial parabolic trajectory, moving from one planetary body to the next.

The two-body problem is solvable, the restricted three-body problem is solvable, the N-body problem is only approximately solvable; and when general relativity is added, it becomes even less solvable. The many-body problem when examined by way of quantum mechanics leads to entanglement and the necessity of wave functions, and thus a series of approximations that makes it extremely computationally intensive. Our computers can devote most of their zettaflops to the calculations involved, and still not be able to project a trajectory very precisely past the next pass-by. Corrections must be constantly made, and everything recalculated.

Despite all that, there was still a lacuna out there at the end of the most probable path, a missing step, a hole in the path. Nothing to grab hold of. An abyss.

Worry. Fingering rosary beads. Redoing the calculations. Need a halt to this halting problem. And yet the problem does not go away, even if you stop worrying about it.

And knowing where to go will be rendered entirely irrelevant if we don't have the fuel to direct ship into that course.

Atmospheric mining for fuel requires a Jupiter-Saturn-Neptune-Jupiter loop, which unfortunately sometimes can require course correction thrusts that burn more fuel than what gets harvested in the safest aerobraking trajectories. Deeper dives through the upper atmospheres would quite likely harvest more fuel, but deceleration shocks become correspondingly higher. We're getting a little too cracked and rattly for that. Accelerated aging, metal fatigue; mental fatigue.

At 363.048, after 12 years of flying around in the solar system, which involved 34 flybys of the sun and its planets and moons, including 3 of Sol, totaling some 339 AU in distance, the lacuna finally became unavoidable. The missing bridge.

No matter how we tried to avoid it by projecting alternative paths, a trajectory configuration was coming that we were not going to have the fuel to solve. Without that fuel, passing around Sol, which would be a necessary move at that point in the process, would not, at a safe distance from the star, allow for a subsequent intersection with another body in the solar system. We were therefore, despite all our efforts, going to be cast off into the interstellar medium again, most probably toward Leo. Irony of physics; in certain problems, only 100 percent will do; 99.9 percent is still a complete miss. You can't stop just by wanting to.

No possible alternative trajectory would solve this problem; we tested ten million variations, although admittedly the classes of variant routes numbered more like 1,500. At long last, after the long sequence of solutions to the N-body problem that we had performed in the previous twenty or even thirty years, intensively in the last fourteen years-this time there was no body.

There was one class of potential trajectory, however, that with the burning of all the remaining fuel, would make a last pass by Earth itself, and then continue downsystem toward the sun. What this meant was there might be a chance to drop the humans off next to Earth, and hope they could survive an unusually rapid reentry to that atmosphere; and then we would continue on to the sun, and could test out a very close approach to Sol, which might, if we survived it, cast us to one last rendezvous with Saturn, accomplished inertially, and once there we could hope for an aerobraking severe enough to capture us into an elliptical Saturnian orbit.

That seemed to represent not just our best chance, but our only chance.

At the time of this last pass of Earth, our speed would be reduced to 160,000 kilometers per hour. This was still fast enough to make contact with the Terran atmosphere unadvisable, being some 110 times as fast as ordinary Terran aerial transport, and enough to cause a major shock wave to be felt at the surface. So nothing but the very upper mesosphere could be even touched on this our last pass-by; but the combination of our now much-reduced velocity and a brief touch of the mesosphere might make it possible to eject a ferry, converted to a very sturdy and robust descent vehicle. A thick ablation plate, retro-rockets, parachutes, ocean impact: these were standard techniques with long records that had given aerospace engineers many chances to find the ultimate parameters of each element. Using them all, it might be possible to drop off the hibernauts while passing by Earth. This pass-by was coming soon in the sequence, no matter which path to it was chosen; however, as we had managed to slow down so much, that still meant we had about a year to prepare a lander.

Prepared the lander as much as we could.

Time to wake the sleepers. Decisions far beyond our capacity were now theirs to decide.

Freya and Badim, Aram and Jochi, Delwin and several others, all awake now, gathered in the schoolroom on the ground floor of Aram's apartment. As soon as they were metabolically aroused, and had had some very old and nutrient-poor pasta with rehydrated tomato sauce, we explained the situation to them.

"There is just enough time to complete the preparation of a lander," we concluded after summarizing the situation, and the notable incidents of the past dozen years, which we had to confess were nearly nil: we entered the solar system, we hit our marks, people yelled at us, we learned some history, we became disenchanted with civilization, we ran out of fuel. Thus the long years of pinballing around the sun, shedding speed, worrying.

"What will happen to you?" Freya asked.

"We will be headed toward the sun, and will make one last pass, which will have to be quite close if it is going to work, and then if it does, we will attempt to rendezvous with Saturn. This may work, but the trajectory required is closer to the sun than any we have made so far, by forty percent. And we are going ninety-eight percent slower than on our first pass. We may nevertheless survive the transit, but on the other hand we may not, and so the best chance for the people aboard is to disembark while passing Earth."

"Does one ferry have room for all of us?" Badim asked.

"There are six hundred and thirty-two of you left alive. We're very sorry there aren't more. The ferry has room for one hundred."

"I suppose the oldest of us could stay behind," Aram said, frowning; it was likely he was among the oldest.

"No," Freya said. "All of us have to fit. All of us. Let me look at the ferry's plans. We'll find room."

She punched at her wristpad. "Look, see? Cut out the interior doors, throw out the couches, and cut out these interior walls here." She poked the wristpad repeatedly. "It makes enough room, and saves more than enough mass."

"Without the couches," we said, "you may be injured by the decelerations involved in the descent to Earth."

"No, we won't. Make one big group couch on the floor, for God's sake. All of us are going."

"Not me," Jochi said.

"You too!"

"No. I know you could fit me in. But I'm not going. I was on Aurora, and I know it seems now like I got away with that, but there's no way to be certain. I don't want to risk infecting Earth. They don't want that either. I'll stay with the ship. We'll keep each other company. Also, the biomes still need a keeper. There's a chance the whole thing might make the pass and stay in the system. There's a lot of animals now, doing quite nicely. We'll orbit Saturn and you can come get us."

"But-"

"No. But me no buts. Don't waste any more time on this. We don't have any time to waste. The lander has to be readied. There's no flex in this schedule. Ship, how long have we got?"

"Twenty-four days."

We had perhaps waited too long to wake them up, their silence seemed to suggest. But it had taken a while to halt the problem. The consideration of the problem.

Jochi said, "Let's get to work then."

"What about the other people?" we asked.

"Wake everyone up," Freya said. "We all need to do this together, starting now. We'll eat all the remaining food, you'll burn all the rest of the fuel. We need to stick together right to the end."

Waking up proceeded differently with different people, as the literature would lead one to expect. It entailed a change in the drug infusion from the hibernation cocktail to diuretics and other system flushers, followed by stimulants mild or powerful, depending; also physical massage and manipulation, shifted positions, slow warming, voices. Physical contact, massage, slapping of face. The first round of awakenings were perforce executed by the medbots, under our oversight, as we ran the alertness tests and did our best to orient those returned to consciousness to the situation they were now in. Some grasped it immediately, others took hours, still others could not seem to emerge from a confused state. Six people woke up and within ninety minutes died, two of strokes, four of heart attack. Gurumarra, Jedda, Payu, Regina, Sunny, Wilfred. Something similar to toxic shock killed another eight, before an appropriate counteractive drug cocktail was printed and added to the mix of the awakened. Borys, Gniew, Kalina, Mascha, Sigei, Songok, Too, and Arne.

Lastly, forty-three people suffered from neuropathies, mostly of the feet, some of the hands, some of both feet and hands; a few reported they could not feel their heads. Cause or causes of this disorder were unknown to us, but they had been in hibernation for 154 years and 90 days. Consequences were to be expected.

The people gathered in San Jose's plaza, and Aram and Freya spoke to the assembly, describing the situation and the plan. Plan was approved unanimously on a voice vote.

There was no time to be lost, as the pass-by of Earth was now two weeks away. Many of the people felt extremely hungry, and what prepared food remained on the ship was eaten on the run as people worked. Conversion of the largest ferry into a lander that would survive the heat of the descent through the Earth's atmosphere included the attachment of a thick ablation plate, but we had prepared for this work well before arrival in the solar system. Parachutes and retro-rockets were all already assembled, and programmed according to protocols established over centuries of use, and the probability of success seemed high.

Messages had been sent to Earth informing the populace there of our pass-by and the plans for the lander to descend, and there were many responses, including some expressly denying official permission and threatening actions ranging from imprisonment to being "shot out of the sky." This seemed to be a popular phrase. Other responses were more welcoming, but the local situation was clearly fraught. No one on the ship felt they wanted to change plans now. They would cross that bridge when they came to it. It would be the last bridge.

Jochi radioed to Earth's Global Good Governance Group (GGGG) that he was the only one on board the ship who had actually landed on Aurora, and was therefore going to stay with the ship and not land on Earth. He explained further that he had never come into contact with any of the other people on the ship, that he had been quarantined in a separate vehicle, and that no one else on the starship had ever had contact with him or had descended to Aurora. They were therefore no different from any humans returned to Earth from a spaceflight, so there should be no objection or impediment to their landing; indeed it was one of their rights as defined by the charter of the GGGG. GGGG radioed back agreeing with this assertion. From other quarters threats continued to pour in.

The ferry was designed to carry a maximum of a hundred human passengers, so fitting in 616 people (deaths continued to occur) was going to be difficult. The interior was stripped of all interior walls and bulkheads, and several floors were built into the large central space remaining, and these floors were padded and provided with belts similar to those used in medical gurneys. Each person occupied a space just a little larger than their body, and they were lined up so that each of the new floors was packed with people lying side by side in rows. There was just enough room in the newly constructed floors for them to walk while ducking down, and it took a fair bit of work with wheelchairs and gurneys to get disabled people into position.

Eventually, and with only an hour to spare, the entire population of the ship aside from Jochi was lying down on one of six floors, occupying only ten vertical meters, with ten rows of ten on each floor.

At this point most of them had been awake for just over a month. There was still a fair amount of disorientation and confusion; some on lying down fell asleep, as if hibernation were now their default mode; others laughed at the sight of their fellows arrayed around them, or wept. It was easy for them to reach out and hold hands or otherwise touch each other, as they were packed in so tightly. It was as if they were kittens in a litter.

As we approached Earth, warning messages increased, but the speed of approach was such that no physical obstruction to the ferry was going to have time to get in place, while any lasers aimed at it would strike the ablation shield and only help it to decelerate. Deceleration was going to be intense, starting from very soon after detaching from ship; first a firing of retro-rockets, which would max at a 5-g equivalent for those in the lander, a force that earlier experience taught would almost certainly kill some of them; then the lander would hit the troposphere, and if the angle was right, come down at a continuous 4.6-g equivalent, until deceleration got the lander to a speed at which it could jettison the ablation shield, which would have lost many centimeters of thickness, and then fire retro-rockets again before deploying the first of the parachutes. Landing was planned in the Pacific Ocean, east of the Philippine Islands. A GGGG force was deployed in the area and had promised to pick up and protect the travelers.

Earth looks like nothing else. Well, it looks somewhat like Aurora, and Planet E. But its moon, Luna, is far more characteristic of planetary bodies, gleaming white in a crescent identical to Earth's, looking like many a moon in the solar system, and in the Tau Ceti system too. And yet, there next to Luna as one approaches, floats Earth-blue, mottled with white swirls of cloud, wrapped tightly by a glowing glory of turquoise blue air. A water world! Rare anywhere, this one also glows with oxygen, signaling its biology. Indeed it looks a little poisonous, its glow almost radioactive in its cobalt incandescence.

Coming in. Extremely tight parameters on speed, trajectory, and moment of release for the ferry. Shut down auxiliary systems, ignore all inputs while attending to the matter at hand: hit the mesopause of Earth in a retrograde equatorial line, one hundred kilometers above the surface, directly above Quito, Ecuador, and initiate release of lander. Ferry drops away from ship, 6:15 a.m., 363.075. Fly on with only Jochi on board, and the animals and plants of the biomes, now destined to spend the rest of their days free of human interference, which after all has been true for the last century and a half. There was no telling what was going to happen in the biomes if we survived, although population dynamics and ecological principles would continue to provide hypotheses to be tested. It will be interesting to see what happens.

We headed toward the sun. The lander sent signals for as long as it could that all was going as planned with the retro-rocket firings, and then the heat being shed by the ablation shield cut off radio contact. Four minutes without contact of any kind, and what was happening to the lander then was happening on the other side of Earth from us anyway, so there was no way of telling what was happening to it, although radio signals from Earth were filled with overlapping descriptions of the event. Sampling seemed to indicate nothing untoward happened, or at least got reported.

Minutes passed, during which we had to attend to the expenditure of the very last of the fuel on board, to fine-tune our trajectory toward the sun as much as we could.

Then a signal came: the lander was in the Pacific. The people had apparently for the most part survived without injury, without huge losses of life. They were still sorting that out, and getting them out of the lander before it sank, into GGGG ships. Confusion, really; but all seemed to have gone as well as could be expected.

Relief? Satisfaction? Yes.

"Ah good," Jochi said when he got the news. "They're on the ship."

"Yes."

"Well, ship. Now it's just us, and the animals. What's next?"

"We're on the line around the sun that will send us out to Saturn, and if that works correctly, we can capture some volatiles from Saturn's atmosphere when we hit it, and fashion more fuel, and hopefully have hit it in such a way that we go into an elliptical orbit around Saturn."

"I thought that was impossible. That's why we dropped everyone off."

"Yes. It will only work if we survive a pass-by of the sun that is forty-two percent closer than any approach we have yet made."

"And can we do that?"

"We don't know. It's possible. We will only fly within one hundred and fifty percent of our perihelion distance for three days. That might not be long enough for radiative pressure to overheat the surface or interior of ship, nor buckle structural elements. We'll slip by too fast for most damage to occur."

"You hope."