Tides of Light

by Gregory Benford

Genres: Alien Contact; Hard Science Fiction; Space Exploration; Space Opera

Synopsis

Now in a new, revised edition, the fourth book of the Nebula Award-winning author's Galactic Center series is a classic tale of man's future and fate--and the greatest mystery from outer space that humanity has ever encountered. Piloting an ancient starship, Killeen and the Bishop tribe escape the mech-ruled world of Snowglade. Seeking refuge on a far away planet, they discover vast wonders-an organic life-form as large as a world, a planet-coring cosmic string, a community of humans ruled by a brutal tyrant, and ultimately an alien race more awesome than any they have encountered. As they battle for survival against these myriad dangers, Killeen and his crew will gain an unforeseen ally-one that may determine humanity's true destiny...

Release date: September 26, 2009

Publisher: Aspect

Print pages: 532

Sample

The Cap’n liked to walk the hull.


It was the only place where he could feel truly alone. Inside Argo there was always the rustle of movement, the rub of humanity kept two years in the narrow though admittedly pleasant confines
of a starship.


And worse, when he was inside, someone could always interrupt him. The Family was getting better at leaving him alone in the
early morning, he had to give them that. He had carefully built up a small legend about his foul temper just after he awoke,
and it was beginning to pay off. Though children might still rush up to him and blurt out a question, lately there had always
been an adult nearby to tug the offending youth away.


Killeen disliked using implied falsehoods—he was no more irritable in the morning than at any other time—but it was the only
way he could think to get some privacy. So no one hailed him over ship’s comm when he was out here. And of course, no ship’s
officer would dare pass through the lock and seek to join him.


And now there was a much better reason not to come out here. Hull-walking just made you a better target beneath the ever-watching
eyes above.


Out here. Killeen had been thinking so firmly about his
problems that he had, as was often the case, completely forgotten to admire the view. Or to locate their enemy escort.


His first impression, as he raised his head to let in all the sweep of light around him, was of a seething, cloud-shrouded
sky. He knew this was an illusion, that this was no planetary sky at all, and that the burnished hull of the Argo was no horizon.


But the human mind persisted in the patterns learned as a child. The glowing washes of blue and pink, ivory and burnt orange,
were not clouds in any normal sense. Their phosphorescence came from entire suns they had engulfed. They were not water vapor,
but motley swarms of jostling atoms. They spilled forth light because they were being intolerably stimulated by the stars
they blanketed.


And no sky back on Snowglade had ever crackled with the trapped energy that flashed fitfully between these clouds. Killeen
watched a sprinkle of bluehot light near a large, orange blob. Its wobbly curves fattened like ribbed, bruised sausages. It
coiled, clotted scintillant ridges working with snakelike torpor, and then burst into luridly tortured fragments.


Could this be the weather of the stars? Snowglade had suffered from a climate that could turn suddenly vicious, and Killeen
supposed the same could be true on the unimaginably larger scale between suns. Since he didn’t understand the way planets
made weather, or the complex fabric of tides and currents, air and water, it was no great leap for him to suppose some similar
shadowed mystery might apply to the raging lives of stars.


Anger forked through this sky. Behind them spun the crimson disk of the Eater, a great gnawing mouth. It ate suns whole and
belched hot gas. In Argo’s flight from Snowglade, which swam near the Eater, they had beaten out against streaming, infalling dust that fed the monster.
Its
great disk was like burnt sugar at the rim, reddening steadily toward the center. Closer in swirled crisp yellow, and nearer
still a bluewhite ferocity lived, an enduring fireball.


Looking outward. Killeen could see on the grandest scale the structure his Aspects told him should be there. The entire galaxy
lurked like a silvery ghost beyond the swarthy dustlanes. It, like the Eater, was a disk—but incomparably greater. Killeen
had seen ancient pictures of the regions beyond the Center, a lake of stars. But that lake did not ripple and churn. Here
tides of light swept the sky, as though some god had chosen Center as her final incandescent artwork. Their target star spun
ahead, a mote among wrack and storm, and all their hopes now bore upon it.


And floating in this seethe, their enemy.

He squinted, failed to find it. Argo was nearing the verge of a jetblack cloud. The distant mech vehicle probably lay somewhere within the obliterating darkness
there. Abraham’s Star was struggling free of the massive shroud. Soon Argo could peer through the shredding fringes of the cloud to find her planets.


A notion tugged at Killeen but he shrugged it aside, caught up in the spectacle all around him. The heavens worked with ribbed
and scaly light, like luminescent beasts drowning in inky seas.


What were the chances, he wondered, that merely showing himself out here would tempt the mech vehicle to skewer him with a
bolt? No one knew—which, in the paradoxical logic of leadership, was why he had to do it.


Killeen had started this hull-walking ritual a year before, at the urging of one of his principal Aspects, a truly ancient
encased personality named Ling. Revered and respected, the Aspect had been given to Killeen by the Family with high attendant
ceremony in Argo’s central hall. Ling was the last remaining true starship Cap’n in the Family chip inventory.
The micromind had commanded a forerunner of Argo and had exciting though often unintelligible yams to tell.


Yes, and following my advice is bringing a reward.


Thinking about Ling had brought the Aspect’s firm, Cap’nly voice sounding in Killeen’ s mind. He let a skeptical frown cross
his face and Ling picked it up.


You make this hull-walk serve the added purpose of displaying your personal calm and unconcern in the face of the enemy.

Killeen said nothing; his sour doubt would faintly trickle down to Ling, like runoff from a rainstorm. He kept up his pace,
making sure his boots got a firm magnetic clamp on the hull before he freed the following leg. Even if he kicked himself free
of the hull, there was a good chance that his low trajectory would carry him into a strut or an antenna down-hull from him.
That would save the embarrassment which he had often suffered when he had started this ritual. Five times he had been forced
to haul himself back to the ship using a thrown, magnet-tipped line. He was sure crew had seen it, too, and had gotten a good
laugh.


Now he made it a point not to have his line even within easy reach on his belt. He kept it in a leg pocket. Anyone watching
him from the big agro pods downhull would see their Cap’n loping confidently over the broad curves of the Argo, with no visible safety line. A reputation for dashing confidence in his own abilities might come in handy in the difficult
times to come.


Killeen turned so that he was facing the pale yellow disk of Abraham’s Star. They had known for months that this was the destination
of their years-long voyage—a star similar to
Snowglade’s. Shibo had told him that planets orbited here as well.


Killeen had no idea as yet what kind of planets these might be, or whether they held any shelter for his Family. But Argo’s automatic program had brought them here, following knowledge far older than their forefathers. Perhaps the ship knew well.


In any case, the Family’s long rest was nearing an end. A time of trials was coming. And Killeen had to be sure his people
were ready.


He found himself loping harder, barely skimming the hull. His thoughts impelled him forward, oblivious to his loud panting
inside the cramped helmet. The rank musk of his own sweat curled up into his nostrils, but he kept going. The exercise was
good, yes, but it also kept his mind away from the invisible threat above. More important, the hard pace cleared his mind
for thinking before he began his official day.


Discipline was his principal concern. With Ling’s help he had drilled and taught, trying to fathom the ancient puzzles of
the Argo and help his officers become skilled spacers.


This was his ambiguous role: Cap’n of a crew that was also Family, a circumstance which had not arisen in the memory of anyone
living. He had only the dry advice of his Aspects, or the lesser Faces, to guide him—ancient voices from eras marked by far
greater discipline and power. Now humanity was a ragged remnant, scurrying for its life among the corners of a vast machine
civilization that spanned the entire Galactic Center. They were rats in the walls.


Running a starship was a vastly different task from maneuvering across the bare, blasted plains of distant Snowglade. The
patterns the Families had set down for centuries were nominally based on crewing a ship, but these years under way had shown
how large the gap was. In a tight
engagement, when the crew had to react with instant fortitude and precision, Killeen had no idea how they would perform.


Nor did he know what they would have to do. The dim worlds that circled Abraham’s Star might promise infinite danger or easy
paradise. They had been set on this course by a machine intelligence of unknown motives, the Mantis. Perhaps the dispersed,
anthology intelligence of the Mantis had sent them to one of the few humanly habitable planets in the Galactic Center. Or
perhaps they were bound for a site which fitted the higher purposes of the mech civilization itself.


Killeen bit his lip in fretted concentration as he loped around the Argo’s stern and rounded back toward midships. His breath came sharply and, as always, he longed to be able to wipe his brow.


He had gambled the Family’s destiny on the hope that ahead lay a world better than weary, vanquished Snowglade. Soon now the
dice would fall and he would know.


He puffed heavily as he angled around the bulbous lifezones—huge bubbles extruded from the sleek lines of the Argo, like the immense, bruised bodies of parasites. Inside, their opalescent walls ran with dewdrops, shimmering moist jewels
hanging a bare finger’s width away from hard vacuum. Green fronds pressed here and there against the stretched walls—a sight
which at first had terrified Killeen, until he understood that somehow the rubbery yet glassy stuff could take the pokes and
presses of living matter without splitting. Despite the riot of plant growth inside, there was no threat of a puncture. Argo had attained a balance between life’s incessant demands and the equally powerful commandments of machines—a truce humanity
had never managed on Snowglade.


As he slogged around the long, curved walls of the lifezones,
here and there a filmy face peered out at him. A crewwoman paused in her harvesting of fruit and waved. Killeen gave her a
clipped, reserved salute. She hung upside down, since the life bubbles did not share Argo’s spin.


To her his reflecting suit would look like a mirror-man taking impossibly long, slowmotion strides, wearing leggings of hullmetal,
with a shirt that was a mad swirl of wrinkled clouds and stars. His suit came from Argo’s ancient stores and had astonishing ability to resist both the heat and cold of space. He had seen a midshipman carelessly
back into a gas torch in one, and feel not a flicker of the blazing heat through its silvery skin.


His Ling Aspect commented:

A reflecting suit is also good camouflage against our mech companion.


This sort of remark meant that the Aspect was feeling its cabin fever again. Killeen decided to go along with its attempt
to strike up a conversation; that might help him tickle forth the slippery idea that kept floating nearly into consciousness.
“The other day you said it wasn’t interested in me anyway.”


I still believe so. It came upon us as though it would attack, yet over a week has passed as it patiently holds its distance
in a parallel path.


“Looks like it’s armed.”

True, but it holds its fire. That is why I advised you to hull-walk as usual. The crew would have noticed any reluctance.



Killeen grumbled, “Extra risk is dumb.”


Not in this case. I know the moods of crew, particularly in danger. Heed me! A commander must imbue his crew with hope in
the mortal circumstances of war. So the eternal questions voice themselves again: “Where is our leader? Is he to be seen?
What does he say to us? Does he share our dangers?” When you brave the hull your crew watches with respect.

Killeen grimaced at Ling’s stentorian tones. He reminded himself that Ling had led far larger ships than Argo. And crew were peering out the frosted walls of the lifezones to watch their Cap’n.


Still, the magisterial manner of Ling rankled. He had lost several minor Faces when Ling’s chip was added, because there wasn’t
enough room in the slots aligned along his upper spine. Ling was embedded in an old, outsized pentagonal chip, and had proved
to be both a literal and figurative pain in the neck.


He gazed once more at the streaming radiance that forked fitfully in the roiling sky. There—he saw it. The distant speck held
still against a far-passing luminescence. He watched the mote for a long moment and then shook his fist at it in frustration.


Good. Crew like a Captain who expresses what they all feel.

“It’s what I feel, dammit!”


Of course. That is why such gestures work so well.


“You calc’late everything?”



No—but you wished to learn Captaincy. This is the way to do so.


Irritated, Killeen pushed Ling back into his mind’s recesses. Other Aspects and Faces clamored for release, for a freshening
moment in his mind’s frontal lobes. Though they caught a thin sliver of what Killeen sensed, the starved interior presences
hungered for more. He had no time for that now. The slippery idea still eluded him and, he realized, had provoked some of
the irritation he had taken out on Ling.


If crew were already harvesting, then Killeen knew he had been running a bit too long. He deliberately did not use the time
display in his suit, since the thing was ageold and its symbols were a confusing scramble of too much data, unreadable to
his untutored mind. Instead he checked his inboard system. The timer stuttered out a useless flood of information and then
told him he had been running nearly an hour. He did not know very precisely how long an hour was, but as a rule of thumb it
was enough.


He wrenched the airlock stays free, prepared to enter, looked up for one last glimpse of the vista—and the idea popped forth,
unbidden.


In a heartbeat he turned the notion over and over, inspecting every nuance of it, and knew it was right.

He studied the sky, saw the course Argo would follow in the gradually lifting gloom of the cloud-shadow. If they had to, there was enough in the sky to navigate
by eye.


He cycled through the axial lock, passed quickly through the tight zero-g vapor shower, and was back inside the spun-up corridors
within a few minutes.


Lieutenant Cermo was waiting for him at the midships gridpoint. He saluted and said nothing about Killeen’s lateness, though
his irrepressible grin told Killeen that the point had not slipped by. Killeen did not return the smile and said
quietly, “Sound quarters.” The way Cermo’s mouth turned down in utter dismayed surprise brought forth a thin smile from Killeen.
But by that time Cermo had hurriedly turned away and tapped a quick signal into his wrist command, and so missed his Cap’n’s
amusement entirely.


He directed the assault from the hull itself—not so much because of Ling’s windbag advice, Killeen told himself, but because
he truly did get a better feel of things out there.


So he stood, anchored by magnetic boots, as sunrise came.

Not the coming of sunlight from a rotating horizon, a spreading glory at morning. Instead, this false dawn came as a gradual
waxing radiance, seen through billowing, thinning grit.


Killeen had noticed that soon Argo would pass across the last bank of clotted dust that hid Abraham’s Star from them. The swelling sunburst would come as the
ship very nearly eclipsed the mech vehicle that was escorting them inward toward the star.


—Still don’t see why the mech won’t adjust for that,—Cermo sent from the control vault.

“It will. Question is, how fast?”

Killeen felt relaxed, almost buoyant. He had committed them, after a week of vexed, fretting worry. If they entered the inner
system around Abraham’s Star with an armed mech vessel alongside, a mere quick command from elsewhere
could obliterate Argo. Best take it out now. If that proved impossible, this was the time to know it.


He searched the quilted sky for a single figure.

—Approaching on assigned path,—Gianini sent.

This young woman had been chosen by Jocelyn to close with the mech. Killeen recalled that she came from Family Rook and knew
her to be an able crewwoman. He followed standard practice in letting his lieutenants choose specific crew for jobs; they
knew the intricacies of talent and disposition far better than he. Gianini had fought mechs back on Snowglade, was seasoned
and twice wounded.


And Killeen found her—a distant dot that sparkled amber and yellow as Abraham’s Star began to cut through the shrouding clouds
that hung over his shoulder, filling a quarter of the sky. The brooding mass had lightened from ebony to muted gray as it
thinned. Shredded fingers of starshine cut the spaces around Argo. And Gianini sped toward the mech, using the sudden rise of brilliance at her back to mask her approach.


A tactic. A stratagem. A life.

A necessary risk, because the mech was too far away to hit with their weapons, which were designed for battles fought on land.
Argo herself carried no weaponry, no defenses.


—I’ll hit it with microwave and IR, then the higher stuff.—Gianini’s voice was steady, almost unconcerned.

Killeen did not dare reply, and had ordered Cermo not to allow any transmissions from Argo, lest they attract the mech’s attention in the ship’s direction. Gianini’s directed transmissions back could not alert the
mech vehicle, though.


As they had calculated, Abraham’s Star began to brim with waxy radiance. Rays refracted through Killeen’s helmet, sprinkling
yellow across his lined face. He found he was clenching and unclenching his hands futilely.



Do it now, he thought. Now!

—Firing.—

He strained, but could see no change in either the dot that was Gianini or the dark point where the mech moved against the
blue background glow of a molecular cloud.


—I can’t see any effect.—

Killeen grimaced. He wanted to give an order, if only to release his own tension. But what would he say? To be careful? A
stupid, empty nattering. And even sending it might endanger her.


—Closing pretty fast.—

Gianini was a softening yellow dot approaching a vague darkness. Action in space had an eerie, dead-silent quality that unnerved
Killeen. Death came sliding ballistically into the fragile shells that encased moist life.


Starshine from behind him swelled and blared and struck hard shadows across Argo’s hull. He felt how empty and barren space was, how it sucked human action into its infinite perspectives. Gianini was a single
point among a countless plethora of similar meaningless points.


He shook off the thought, aching to do something, to be running and yelling and firing in the midst of a suddenly joined battle that he could feel.


But above him the dots coalesced in utter silence. That was all. No fervor, nothing solid, no sure reality.

Burnished sunlight raked the hull around him. Time ticked on. He squinted at the sky and tried to read meaning into mere twitches
of random radiance.


—Well, if that don’t damn all.—

What? he thought. His heart leaped to hear Gianini’s voice, but her slow, almost lazy words could mean anything.


—This thing’s had its balls cut off. Ruined. All those antennas and launchers we saw in closeup, ’member? Their power source
is all blowed away. Nothin’ here that works
’cept for some drive chambers and a mainmind. Guess that’s what led it our way.—


Killeen felt a breath he had been holding forever rush out of his chest. He chanced a transmission. “You’re sure it can’t
shoot?”


—Naysay. Somethin’ pranged it good. A real mess it is here.—

“Back off, then.”

—You want I should skrag the mainmind?—

“Yeasay. Leave a charge on it.”

—Doin’ that now.—

“Get clean clear before you blow it.”

—I’ll put it close, be sure.—

“No contact, just leave it—”

Killeen’s ears screamed the horrible sound of circuit ringing—a long high oscillating twang as a load of electrical energy
bled off into space, acting as an involuntary antenna as raw power surged through it.


“Gianini! Gianini! Answer!”

Nothing. The ringing wail steepled down into low frequencies, an ebbing, mournful song—and was gone.

“Cermo! Suit trace!”

—Getting nothing.—Cermo’s voice was firm and even and had the feel of being held that way no matter what.

“Damn—the mainmind.”

—Figure it was on a trigger mine?—

“Must’ve.”

—Still nothing.—

“Damn!”

—Maybe the burst just knocked out her comm.—

“Let’s hope. Send the backup.”

Cermo ordered a crewman out to recon the mech vehicle. But the man found Gianini floating away from the wrecked
craft, her systems blown, her body already cold and stiff in the unforgiving vacuum.


Killeen walked stiffly down the ceramo-corridors of the Argo, his face as unyielding as the walls. The operation against the mech was a success, in the sense that a plausible threat
to the ship was removed. They had detonated the charge Gianini had left behind on the mech, and it had blown the vehicle into
a dozen pieces.


But in fact it had been no true danger, and Killeen had lost a crewwoman discovering that fact.

As he replayed their conversation in his mind he was sure he could have said or done nothing more, but the result was the
same—a second’s carelessness, some pointless close approach to the mainmind of the vehicle, had fried Gianini. And had lessened
Family Bishop that much more, by one irreplaceable individual.


Numbering fewer than two hundred, they were perilously close to the minimum range of genotypes which a colony needed. Any
fewer, and future generations would spiral downward, weighed by genetic deficiencies.


This much Killeen knew, without understanding even a smattering of the underlying science. Argo’s computers held what they called “DNA database operations.” There was a lab for biowork. But Family Bishop had no Aspects
who knew how to prune genes. Basic bioengineering was of marginal use. He had no time and even less inclination to make more
of such issues.



But Gianini, lost Gianini—he could not so brusquely dismiss her memory by seeing her as simply a valuable carrier of genetic
information. She had been vibrant, hardworking, able—and now she was nothing. She had been chipstored a year ago, so her abilities
survived as a spectral legacy. But her ghostly Aspect might not be revived for centuries.


Killeen would not forget her. He could not.

As he marched stiffly to his daily rounds—delayed by the assault—he forced the somber thoughts away from him. There was time
for that later.


You are acting wisely. A commander can feel remorse and can question his own orders—but he should never be seen to be doing
that by his crew.

Killeen gritted his teeth. A sour bile settled in his mouth and would not go away.

His Ling Aspect was a good guide in all this, but he still disliked the calm, sure way the ancient Cap’n laid out the precepts
of leadership. The world was more complex, more darkly crosscurrented, than Ling ever allowed.


You assume too much. I knew all the tides that sweep you, when I was clothed in flesh. But they are often hindrances, not
helps.


“I’ll keep my ‘hindrances,’ little Aspect!”

Killeen pushed Ling away. He had a role to fulfill now and the small chorus of microminds that he felt calling to him could
be of no help. He had followed Ling’s advice and decided to continue with the regular ship’s day, despite the drama of the
assault. Returning to ordinary routine, as
though such events were within the normal course of a ship’s life, would help settle the crew.


So he had told Cermo to carry on as planned. Only now did he realize what that implied.

Killeen rounded a corner and walked toward the open bay where the crew of the morning’s watch waited. Halfway there Cermo
greeted him with, “Punishment hour, sir?”


Killeen stopped himself from clenching his jaws and nodded, recalling the offense from yesterday.

Cermo had caught a crewwoman in the engine module. Without conferring with his Cap’n, Cermo had hauled her—a stringy, black-haired
woman named Radanan—unceremoniously out into the lifezone, barking out his relish at the catch. The deed was publicly exposed
before Killeen had a chance to find other means to deal with it. He had been forced to support his officer in the name of
discipline; his Ling Aspect had drilled that principle into him.


“Yeasay. Proceed.”

“Could give her more, y’know.”

“I said proceed.”

He had firmly resolved to speak as little as possible to his officers during ordinary ship operations. He was like a drinker
who could not trust himself to stick to moderate amounts. In Family meetings he gave himself a little leeway, though. There,
eloquence and even outright oration served his ends. He knew he was not very good at talk, and the briefer he was the more
effect it had. As Argo had approached this star system he had gotten more and more terse. There were days when most of the crew heard him say only
a short “ah-mmm” as he pointedly cleared his throat at some demonstrated inadequacy.


As they made their way to the central axis Killeen set his face like stone. He was ashamed of his aversion to watching punishment.
He knew that to punish a crewmember was a
sign of his own failure. He should have caught the slide in behavior before it got this far. But once the event had occurred
there was no turning back.


In this case, Radanan had been trying to sneak into the thrumming dangers of the engine zone as they decelerated. This alone
would have been a mild though flagrantly stupid transgression. But when Cermo caught her she had bristled, bitterly angry,
and had called on some friends nearby, trying to provoke a minor mutiny.


A wise Captain hands out rougher justice than this.

His Ling Aspect offered this without being summoned. “She just screamed and swore some, is all,” Killeen subvocalized. “And
was stupid enough to take a poke at Cermo.”


Mutiny is a capital offense.

“Not on the Argo.”


She’ll incite others, harbor resentment—

“She was looking for food, just a minor—”

You’ll lose control if—

Killeen damped the Aspect’s self-righteous bark into silence.

Evidently Radanan had been looking for a way to scavenge something extra, though Killeen could not imagine what she thought
she might find. Usually, crew were caught pilfering food, an outcome of the strict rationing Killeen had imposed for a year
now.


The watch crew stood a little straighter as Killeen came
into the area. Radanan was at the center of a large circle, since this was both a shipboard matter and a Family reproach.
She looked down dejectedly. Her eyes seemed to have accepted already the implications of the cuffs around her wrists that
held her firmly to a mooring line.


Cermo barked out the judgment. Two crewmen stood ready to hold Radanan at the elbows in case she should jerk away from the
punishment. She bleakly watched as Cermo brought out the short, gleaming rod.


Killeen made himself not grit his teeth. He had to enforce his own rules or else nothing he said would be believed. And he
did blame himself. The woman was not overly bright. She had originally been a member of Family Rook.


By tribal consent, all those who had chosen to set off in the Argo had realigned, so that they constituted a new Family