Ilium (8 page)

“Reach Mars in a few days,” repeated Ri Po. “What are the delta-v factors leaving Io’s flux tube?”

“Just under three thousand gravities,” said the integrator. “
Earth
g’s.”

Mahnmut, who had never experienced a gravity-load greater than Europa’s less than one-seventh Earth-g, tried to imagine 21,000 such g’s. He couldn’t.

“During acceleration, the ship, including
The Dark Lady,
will be packed with gel,” said Orphu of Io. “We’ll be as comfy as circuit chips in a gelatin mold.” It was obvious that Orphu had been involved in planning the spacecraft and Ri Po in observing the two worlds. Koros III had probably had advance warning about his command role in such an expedition. It seemed to Mahnmut that only he had been left out of the preparation for this mission, probably because his role—driving
The Dark Lady
through the Martian seas—was so unimportant. Perhaps, he thought, I should opt out of this expedition after all.

Proust?
he tightbeamed the big Ionian.

Too bad we aren’t going to Earth, my friend. We could visit Stratford-on-Avon. Buy a souvenir mug.

It was an old joke between them, but in the present context, it seemed funny again. Mahnmut tightbeamed a decent simulacrum of Orphu’s heavy laughter and the big construct rumbled so heavily in return that all four of the others could hear it through the thick air.

Ri Po was not laughing. He was obviously computing. “Such a scissors’ fling would give us an initial velocity of almost two-tenths light speed, and even after drastic magnetic scoop deceleration in-system, we’ll have an approach velocity of about one-thousandth light speed—more than 300 kilometers per second. We’ll get to Mars quickly enough, even while it’s on the far side of the sun as it is now. But has anyone given any thought as to how we might slow down once we get there?”

“Yes,” said Orphu of Io, his rumbling abating. “We’ve given that some thought.”

Even after thirty Jovian years of existence, Mahnmut had no one to say good-bye to on Europa. His exploration partner, Urtzweil, had been destroyed in a closing lead near Pwyll Crater eighteen J-years earlier, and Mahnmut had grown close to no other conscious entity since then.

Sixteen hours after the conference, Conamara Chaos Central ordered dedicated orbital tugs to lift
The Dark Lady
out of an open lead and boost it into orbit, where hard-vac moravecs, supervised by Orphu of Io, tucked the submersible into the waiting Marscraft and let ancient inter-lunar induction haulers truck the stack downhill to Io. Mahnmut and the other three expedition moravecs had briefly discussed naming the spacecraft, but imagination failed them, the impulse faded, and from that point on they referred to it only as “the ship.”

Like most spacecraft constructed by moravecs in the thousands of years since spacefaring began, the ship was something less than elegant, at least by classical standards. It was one hundred and fifteen meters long and was comprised primarily of buckycarbon girders, with wrinkled radiation-shield fabric wrapped around module niches, semiautonomous sniffer probes, scores of antennae, sensors, and cables. This ship was notably different from Jovian-system machines primarily because of its gleaming magnetic dipole core and its sporty outrider deflectors. Packed away in its lumpy snout were four fusion engine bells and the five horns of the Matloff/Fennelly scoop. A ten-meter-wide pimple on the stern held the folded boron sail. Neither scoop nor sail would be needed until the deceleration part of the journey and the fusion engines had nothing to do with the acceleration phase of the mission.

Mahnmut stayed inside
The Dark Lady
—now packed with gel—while Koros III and Ri Po rode sixty meters away in the forward control module they’d come to call the bridge. The plan was for Ri Po to handle all navigation chores during their brief mad-mouse ride in, while Koros III served as titular commander of the expedition. The plan also called for the Ganymedan to transfer to Mahnmut’s submersible shortly before
The Dark Lady
—emptied of its gel—was to be dropped into the Martian atmosphere. Once in the oceans of Mars, Mahnmut was to serve as a taxi driver—delivering Koros III to whatever landing point the commanding Ganymedan chose for his land-based spying. Koros had been downloaded various specifics of the mission that would not concern Mahnmut.

Orphu of Io had installed himself in his crèche on the outer shell of the ship behind the ten solenoid toruses and in front of the sail-cable struts, and was connected to the bridge and the submersible by every sort of voice, data, and comm link imaginable. Most of his nontechnical conversation was with Mahnmut.

I’m still most interested in your theory of the dramatic construct of the sonnets, my friend. I hope we live long enough for you to analyze more of the cycle.

But Proust!
responded Mahnmut.
Why Proust when you can spend all of your existence studying Shakespeare?

Proust was perhaps the ultimate explorer of time, memory, and perception,
replied Orphu.

Mahnmut made a static sound.

The scarred Ionian sent his rumble through the audio line. “I look forward to convincing you that both can be enjoyed and learned from, Mahnmut, my friend.”

Koros III’s message came over the common line—
Everyone might want to raise bandwidth on the visual lines. We’re approaching Io’s plasma torus.

Mahnmut opened all visual feeds as requested. He preferred to watch external events through Orphu of Io’s lenses, but at the moment the more interesting views were from the forward ship cameras, and not necessarily in the visible-light spectra.

They were accelerating toward the great red-and-yellow-blotched face of Io, coming at the moon from below the plane of the ecliptic and making ready to pass over its northern pole just before flying into the Io–Jupiter flux tube.

During the short trip in from Europa, Orphu and Ri Po had downloaded pertinent information about this region of Jupiter space. A creature of Europa, Mahnmut had always focused primarily on sonar and some visual-light perception within the black oceans there, but now he perceived the Jovian magnetosphere as the loud, crowded place it was. Looking ahead on the decametric radio bandwidths, he could see Io’s Jupiter-thick plasma torus and, at right angles to the torus, Io’s flux tube running like wide horns to Jupiter’s north and south poles. Far beyond Jupiter and its moons, beyond the magnetopause, Mahnmut could sense the bow shock turbulence crashing like great white waves on a hidden reef, could hear the upstream Langmuir waves singing in the magnetic darkness past that reef, and could pick out the ion acoustic waves crackling after their long voyage uphill from the sun. The sun itself was little more than a very bright star from Jupiter space.

Now, as the ship swept up and over Io and into the flux tube, Mahn-mut could hear the Whistler-mode chorus and hiss that the little moon made as it plowed through its own plasma torus, eating its own tail, as it were. He could see the deep bands of equatorial emissions and had to tone down the decametric and kilometric radio roar coming from the flux tube itself. All of Galilean space was a furnace of hard radiation and electromagnetic activity—Mahnmut had spent his whole existence with its background roar in his virtual ears—but passing from torus to flux tube so close to Jupiter sent violent cascades of tortured electrons hissing around their ship like banshees screaming to be let in a beleaguered house. It was a new experience and Mahnmut found it a bit unnerving.

Then they were in the flux tube and Koros III shouted “Hang on!” before sound channels were drowned out by the hurricane roar.

The Io plasma torus was a giant doughnut of charged particles stirred up within the trail of sulfur dioxide, hydrogen sulfide, and other gases left behind—and then accumulated again—by Orphu’s violent home moon. As Io sped in its fast 1.77-day orbit around Jupiter, slicing through the gas giant’s magnetic field and plowing into its own plasma torus, it created a huge electrical current between Jupiter and itself, a double-horned cylinder of incredibly concentrated magnetic surges called the Io flux tube. The tube connected to Jupiter’s north and south magnetic poles and created wild auroras there, while the horns of the flux tube itself carried a constant current of some five megaamperes and constantly produced more than two trillion watts of energy.

The Five Moons Consortium had decided some decades ago that two trillion watts of energy would be a terrible thing to waste.

Mahnmut watched as Io’s north pole flicked beneath them. Ejecta from various sulfur volcanoes—especially from Prometheus far south near the moon’s equator—was being spewed 140 kilometers high and higher above the pockmarked surface, as if the violent moon was shooting at them, trying to make them turn back before they reached the point of no return.

Too late. They were already there.

On the common forward video, Ri Po’s superimposed navigation brackets showed their proper insertion into the flux tube and projected alignment with the scissors. Jupiter rushed at them, rapidly filling the view ahead like a multi-striped wall.

The physical blades of the scissors—that dual-armed, rotating, magnetic wave accelerator set within the natural particle accelerator of Io’s flux tube—were 8,000 kilometers long, only a fragment of the flux tube’s length of more than half a million curving kilometers connecting the north pole of Io to the north pole of Jupiter.

But the scissors could move. As Orphu of Io had explained to Mahnmut, “Angular momentum can be a many-splendored thing, my little friend.”

The ship nestling Mahnmut’s beloved submersible had approached Io and the flux tube—even after full acceleration from the ion-tugs—at a velocity of only some 24 kilometers per second, less than 86,000 kilometers per hour. At that speed, it would take more than four hours just to traverse the flux tube distance between Io’s north pole and Jupiter’s, e-years to reach Mars. But they had no intention of continuing on at that creeping pace.

The ship entered the crackling, roaring, twitching field of the flux tube, found the vertex of the scissors, aligned itself with the upper blade, and then used the tube’s own accelerator properties to hurl the spacecraft-solenoid through the five-kilometer-wide field coils of the superconducting dipole accelerator. As soon as the ship entered the first gate like some clumsy croquet ball passing through the first of several thousand wickets, the blade of the accelerator-scissors began snapping open with a differential angular velocity nearing—and theoretically even surpassing—light speed. They were riding a rippling bullwhip one second and then flicked from the tip of it the next, using as much of that two trillion watts of energy as the scissors-accelerator could grab.

The ship—and everything in it—went from zero-g to almost 3,000-g’s within two-point-six seconds.

Jupiter zipped toward, past, and under them in an eyeblink. Mahnmut slowed all his monitors down so that he could appreciate their departure.

“Wheeehaw!” cried Orphu from the outer hull.

The ship and submersible strained, creaked, groaned, and whinnied from the g-force, but it was all made of tough stuff—
The Dark Lady
itself had been built to withstand several million kilograms per square centimeter of pressure in Europa’s deep seas—and so were these moravecs.

“Holy shit,” said Mahnmut, meaning to send the comment just to Orphu of Io, but managing to broadcast to all three of his colleagues.

“Indeed,” responded Ri Po.

Jupiter’s broiling polar lights—the brilliant auroral oval surrounding the gas giant’s north pole, accompanied by Io’s blazing footprint where the flux tube met atmosphere—flashed beneath them and disappeared astern.

Ganymede, which had been a million kilometers away across the system a few seconds before, zoomed toward them, flicked past, and was lost to sight behind them.

“Uruk Sulcus,” said Koros III on the common band and for a moment Mahnmut thought the command-moravec was choking or cursing before he noted the slightly sentimental tone to his usually cool voice and realized that Koros must have been referring to some region on Ganymede itself—a half-glimpsed grooved and dirty snowball flashing past—that must be home to the Ganymedan.

The tiny moon Himalia, which none of the crew had visited—nor cared to—whipped by like a firefly with its hair on fire.

“We’ve passed through the bow shock front,” reported Ri Po in his flat Callistan accent. “Out of the local pond for the first time, at least for this moravec.”

Mahnmut glanced at his screens. Ri Po’s readout reported that they were fifty-three Jupiter diameters out now and still accelerating. Mahnmut had to check unused memory banks and see that Jupiter had a diameter of almost 142,000 kilometers before he got a sense of their speed. The ship was arcing above the plane of the ecliptic, but Mahnmut vaguely remembered that the plan was for the sun’s gravity to hook them back down toward Mars, which was on the far side of the sun at the moment. At any rate, navigation wasn’t his concern. His job would begin when they landed in the ocean of Mars, and sailing there seemed simple enough—rich sunlight, warm temperatures, shallow depths with no pressure to speak of, stars to navigate by at night, geo-positioning satellites that they’d drop into orbit so they could navigate during the day, almost no radiation compared to the surface on Europa. No kraken! No ice.
No ice!
It all seemed too simple.

Of course, if the post-humans were hostile, there was a good chance that the moravecs would not survive the trip to Mars or the atmospheric entry, and even they did, there was a high probability that they could never return to their homes in Jupiter space, but there was nothing Mahnmut could do about any of that now. His thoughts began to turn back to Sonnet 127.

“Everyone all right?” asked Koros III.

Everyone reported in that they were fine. It took more than a few thousand gravities sitting on their respective chests to get this crew down. Morale was high.

Ri Po began reporting some other navigational and spacefaring facts, but Mahnmut wasn’t really paying attention. He was already caught up in the gravity field of Sonnet 127, the first of the “Dark Lady” sonnets.