Perhaps the Deep began as an . . . an awareness of change. Of plumes of heat bubbling up from cracks in the solid crust beneath it. Of the seep and flow of sulfur and metallic compounds emerging from volcanic vents and keeping the water above liquid.

Perhaps it had evolved ways to affect this leakage somehow. Like predators developing intelligence in order to better hunt their prey, the Deep had developed intelligence to manipulate its deepest surroundings, finding new sources of heat and developing them, expanding them, making use of them. Without being told, I was aware that the Deep must be a true thermovore, deriving sustenance directly from heat.

And after that . . .

Had the unending boredom of existence generated within the Deep an interest in, even a fascination for, mathematics? Surely, though, there had to be intelligence before the boredom, for the boredom to be realized. A non-sentient lump of ice could not be bored.

Why was the Deep super-intelligent?

Did there have to be a reason? I felt that I was on the right track about controlling its environment-that, after all, was a large part of what had led to human sentience. Perhaps, eons past, intelligence, sentience had appeared here on a very small scale . . . a simple curiosity about its surroundings, an awareness of cold and dark, and of plumes or currents of heat rising through its inner substance.

And that had led to trying to control those currents . . . the gods alone know how. Had the Deep learned to change, to control, those incredible pressures within itself? Or to use those pressures to redirect warm currents to where they needed to be?

Eventually, with the passage of enough time, perhaps that Mind had developed mathematics, simply as a means of measuring what it knew . . . depth, pressure, hot and cold, flow rate, distance.

How it might have progressed from there to Gdel encoding was utterly beyond me. Its understanding of mathematics would have started with counting, and counting would have led to arithmetical manipulations . . . and that to prime numbers, and that to factoring primes.

Could intelligence bootstrap itself from simple awareness of physical events to higher mathematics, simply through introspection, through self-aware mindfulness?

Given the slow passage of enough millennia, perhaps . . .

But now the universe of the Deep had suddenly expanded with the arrival of other intelligences from off world. It had for the first time seen the planet it inhabited from outside, heard the discussion of some of those alien intelligences, and realized that it was doomed.

The sheer injustice had me on the verge of sobbing . . . or was I picking up some sort of emotional leakage from the Deep? It was hard to tell, so closely entwined at that moment were its thoughts with mine. But a life form as intellectually capable, as smart as the Deep was completely helpless in the face of its world's inevitable doomsday.

What could be done to help?

Not evacuation, certainly. There was no way to load the Deep from GJ 1214 I into a spaceship and carry it to some other world. You might as well think about moving the entire planet. . . .

And with that thought, I began to emerge from the dream.

"Doc? Hey, Doc? You okay?"

I opened my eyes. I was in one of the racks in the sunken base's makeshift sick bay, staring at a dark and pressure-crumpled overhead. "W-what . . . ?"

It was Staff Sergeant Thomason . . . but he'd been left up on the surface, hadn't he? What was he doing down here?

I sat up with a gasp. Gods . . . had that been real?

"Whoa, easy there, Doc. You've been out of it for the better part of a day!"

A day! "What . . . what happened? The brain . . . the Gykr . . ."

I knew I wasn't making any sense. I swung my legs off the bunk and leaned forward. I started to sag, dizzy, and Thomason caught me. "You stay put for a moment, Doc. Everything is okay. Everything is very okay."

"No it's not," I told him, still muzzy. "We've got to save the whole fucking planet. . . ."

Chapter Twenty-Three.

Okay, so I wasn't thinking straight just then. But I meant well.

A few hours later, I was back on the surface, entering our dome and receiving rounds of congratulations from Marines and scientists alike. They seemed to be of the impression that I had somehow saved the expedition.

All four of the Gykr had reached the surface already. It turns out that the cuttlewhales had gotten involved-the cuttlewhale express, we were calling it. The Walsh would move out into open water, a cuttlewhale would move up behind it and swallow it down, and a short time later the sub would be released at its destination, alongside the sunken base or beside the new base at the surface. Over the course of an afternoon, the Walsh had transported all four Gykr, the four M'nangat, and twenty-some of the other survivors to the surface, and was now making her final trip.

But the big news was that when the Walsh surfaced with that very first Gykr, it was to the discovery that the Gykr starship had returned during our absence . . . and, as expected, had brought along some friends. Space around GJ 1214 I was now occupied by eight orbiting alien starships, and they'd come loaded for bear.

Or, in this case, human.

The base we'd nanufactured on the ice had been well hidden and remained undiscovered. But when Walsh had surfaced, the Gykr aboard had immediately contacted his friends. He'd been released at the edge of the ice, and a ship had arrived shortly afterward to pick him up.

That Gykr, though, had become a Chosen during the ascent; he'd been the only Gykr aboard, after all, and apparently it was being alone that triggered the greater sense of independence, the ability to give orders, among Gykr individuals. And apparently that Gykr Chosen had been impressed enough with the agreement I'd hammered out with them that he'd told his friends . . . and they'd been impressed as well. They'd not even demanded-as our informal treaty had stated-that they take over control of the rescue. They simply constructed a surface base of their own, and then watched closely as Walsh continued to shuttle personnel up and down.

Exactly how the Gykr fleet was choosing to interpret that treaty, or our activities, was unknown as yet. Captain Summerlee felt, however, that anything other than an immediate attack counted as a positive step. She'd ordered the Haldane to land on the ice near the dome, and for several hours now, the two sides, human and Gykr, had been warily watching each other.

Yes, the Skipper was back in command. Chief Garner had used the ship's medical 3D printer to run off a batch of hESC-human Embryonic Stem Cells-and injected them into her brain to repair the damage there. Her in-head implants were still down, and she would need to have partial replacements regrown when she got back to Earth. There was nothing to stop her from resuming command, however. After all, she had plenty of people on her command staff who could access AIs, navigational and engineering data, and ship's departmental reports and handle them for her . . . and she could call up paperwork on her office viewall rather than within open mental windows. Her toughest problem would be remembering manual overrides for things like shipboard elevators and coffeemakers.

She was waiting for me at the entrance to the Haldane's mess deck when I walked in. "Captain Summerlee! Ma'am!"

"Welcome back, Carlyle. I'm told that you've been busy."

"Busy enough, Captain. I'm afraid I may have committed Humankind to a new long-term project."

"Well, it'll have to be ratified by the Commonwealth Senate. They normally take a dim view of enlisted personnel forging diplomatic agreements with aliens. In this case, though, I think they'll be willing to overlook the embarrassing details, in exchange for a solid peace treaty with the Gucks."

I blinked at her for a moment, not quite comprehending. "Actually, ma'am," I managed after a slack-jawed moment, "I wasn't talking about the Gykr."

She gave me a Look. "Don't tell me you've gone and established diplomatic relations with someone else! First the Qesh . . . then the Gykr. Now who?"

"The Abyss Deep," I told her.

"The what?"

So I explained.

It was actually a bit embarrassing, because once I actually started describing my exchange with the Deep, I realized that I didn't have any actual proof that what I'd seen was . . . real. The whole exchange could so easily have been a hallucination, something I'd imagined in vivid detail, perhaps, while unconscious.

"He's right," Gina Lloyd said, at least partially validating my wild story. "I could hear parts of the conversation in the Walsh. I couldn't see anything, though."

"You were halfway back to the surface," I told her.

"And inside a cuttlewhale," she agreed. "But I think we were . . . on the same wavelength? Like when it was asking about Dr. Murdock. And . . . when it said it was a billion years old, I had shivers going down my spine. I think maybe it has some kind of channel open in us, y'know?"

"That's as good a theory as anything else I've heard," Summerlee said. "Come on. We're going to have an emergency pow-wow."

"Emergency?"

"The Gykr have asked us to leave the system," the captain said. "They did ask nicely . . . for them. But they want us out of here in one orbit of Abyssworld around its sun. That's one day, fourteen hours, or thereabouts. And we have to decide how we're going to respond."

The mess deck was crowded. Garner was there, and Doob and McKean. Gunny Hancock was there, looking wan and pinched, his stump wrapped in a surgical sealer that told me they'd already started working on growing him a new left arm. Kemmerer was present, and most of the other Marine officers, too, as were Haldane's department heads. All seven Brocs-our three, plus the four rescued from the sunken base, were occupying a far corner like a thick clump of small trees. It was a full crowd, and apparently no one cared to telecommute this time.

"Thank you all for coming," Summerlee said, taking her spot at the head of the longest mess table. "Before we get started, I know you'll all join me in welcoming HM2 Carlyle back from the Murdock base. While there, Mr. Carlyle was instrumental in defusing what was potentially a very nasty situation with the Gykr, and got them to accept a scheme that allowed both our people and them to leave the sunken base."

There was applause from the audience, and a few shouts of "Go, Doc!" and similar sentiments.

Summerlee held up her hands, motioning for silence. "In addition," she said as the ruckus quieted, "I'm given to understand that Mr. Carlyle also, while inside the Murdock facility, made contact with an alien life form, an extremely large and extremely intelligent life form, native to this world. Mr. Carlyle has provisionally named this organism 'the Deep.' Mr. Carlyle? Perhaps you'd tell us all about this . . . this extraordinary being."

I stood, awkward and unsure of myself, and began talking. I described the Deep, my hallucinogenic impressions of it, and what I thought it actually was . . . an immense, sessile thermovore evolved from dirty exotic ice under inconceivable pressure.

"The creatures we call cuttlewhales," I concluded, "appear to be artificially fabricated somehow by the Deep inside the exotic ice mass. For probably some millions of years, it has been using the cuttlewhales as a kind of sensory system, letting it see itself from the inside. More recently, it has learned that there is an outside as well, and begun sending the cuttlewhales up to Abyssworld's surface, as remote probes.

"As a result-and partly because of the Deep's, ah, unexpected interface with me-it has learned that this world is tidally locked in close orbit around its star . . . and that in a short time, cosmically speaking, the heat from that star is going to strip this planet of its ocean. When that happens, the Deep, which depends on both water and on intense pressures, will be killed."

"You say this Deep thing is immortal?" Ortega said.

"Except for the fact that its environment is going to go away soon, yes, sir."

"Does it reproduce?" Montgomery asked. "Can it reproduce?"

"Where? It makes up three-quarters of the volume of this planet!"

"I don't know. I was wondering about being able to transfer germ cells to a new home, somehow."

"As far as I could tell, ma'am, no. It . . . developed awareness, sentience, a long time ago as a result of various ebbs and flows of heat, minerals, and so on deep inside its substance, its body, if you will. I imagine parts of that body replace themselves over the centuries . . . although, really, there doesn't appear to be anything like a genome with a built-in timer or destruct sequence, like human DNA."

"We should probably think of it," Lieutenant Ishihara said, "not as a life form, but as a kind of natural AI . . . an enormous computer, in fact."

"It takes in nutrients and energy, sir," I told the engineering officer, "and it generates order out of chaos. I would say it's alive."

"So does a computer, young man," Ishihara told me, "if by order you mean accumulating and storing useful information. Oh, I'm not saying this thing isn't worth saving! The mathematical information it has stored within its matrix alone must be staggering!"

I didn't reply to that. Ishihara hadn't been there, hadn't felt himself wired in to the Deep's emotional processes. It was alive . . . and it was self-aware. Computer AIs were neither. They could simply act as though they were self-aware with the appropriate programming, and we humans were too slow to tell the difference.

Or . . . did he have a point? Was that what was going on in the Deep, a system that mimicked what we thought of as sentient self-awareness?

Well for that matter, what proof did we have for human self-awareness? We thought we were, sure, but there was no way to prove that it wasn't a kind of all-embracing illusion, like the old philosophical chestnut that said we only thought we had free will in a fixed, predestined timeline.

"Well, whether it's alive or not, how the hell are we supposed to rescue it?" Chief Garner asked.

"That," I told them, "is the easy part. The hard part will be waiting it out."

I'd given the problem a lot of thought, and checked in with the Walsh's AI during our ascent to the surface. Haldane's larger and more powerful AI agreed with me. We could save the Deep.

It would just take some time.

The concept of the "gravity tractor" has been with us for a long time. Back in the early twenty-first century, as humans became aware of the terrifying threat posed to civilization, even to all life on Earth, by asteroids like the one that wiped out the dinosaurs 65 million years ago, we examined a lot of schemes for changing the orbit of an incoming cosmic missile. You couldn't just blow the thing up with nukes; the individual fragments would continue on the original trajectory, and might even end up doing more damage than the original intact flying mountain.

One promising mechanism was the idea of parking a spacecraft near the asteroid and keeping it there, possibly with solar sails, possibly with a steady, low-thrust ion drive, and letting the gravity of the spacecraft deflect, ever so slightly, the path of the asteroid.

Oh, it would take a long time, of course . . . centuries, perhaps. The thrust provided by that tiny gravitational impulse would be microscopic, but over year upon year upon year, the effect would add up. Catch the killer asteroid early enough, and you would be able, eventually, to deflect its course just enough to miss Target Earth.

We also, back then, were beginning to learn just how chaotic early solar systems were. As accreting worlds formed around their parent star, planetary bodies interfered with one another, collided with one another, nudged one another gravitationally into entirely new orbits. We now know that in our own Solar System, four and a half billion years ago, Jupiter and Saturn had developed a one to two resonance with each other, Jupiter circling the sun once for every two orbits of Saturn. As a result, Jupiter had been nudged closer to the sun while Saturn had been pushed farther out, and that dual migration had generated the cascade of orbital changes leading to the late heavy bombardment of the inner system 600 million years after its birth.

Orbital resonance could remake or destroy a planetary system, could move gas giants from the remote outer portions of the star system in to tight, close orbits-the "hot Jupiters" discovered in such numbers in the early days of exoplanet discoveries a couple of centuries ago, because they were so massive and had such short periods.

And in the same manner, worlds could be summarily ejected from their home star systems entirely. The Gykr Steppenwolf homeworld, a rogue and sunless planet adrift in interstellar space, was an example.

So what did that have to do with saving the Deep?

Everything, really.

There were several outer gas giants orbiting GJ 1214, together with GJ 1214 II, a Mars-sized world 10 million kilometers out from the star, and with an orbital period of just over sixteen days. What if we could change Planet II's orbit, actually nudge it into a period of, say, precisely half that of Abyssworld-to nineteen hours or so? Properly calculated and executed, the two-to-one resonance would bump Planet II in closer to the star, and shove Abyssworld farther out. By working out the numbers to enough decimal places, we could plop Abyssworld down in just about any orbit we pleased . . . one where the dayside was pleasantly habitable . . . or even one far enough out that the entire world-ocean froze over. That wouldn't bother the Deep one bit.

It would take a hell of a long time of course, but so what? A million years? Ten million? Hell, even if readjusting Abyssworld's orbit took a hundred million years, the Deep had time. A million centuries is a mere 10 percent of the billion years it would take the planet's ocean to finally boil away.

And there was the additional promise that human technology would rapidly advance to the point where slinging planets around a star system was child's play. What would we be capable of in just a few thousand years? Generating artificial black holes, perhaps, and using directed gravitational singularities to change planetary orbits? Or perhaps we would command even more advanced and magical technologies as yet undreamed of.

A billion years was plenty of time. . . .

The downside was that we humans have a pathetically brief attention span, and a political will that rarely extended past the next elections. What if we simply never got around to doing something about it? After all, there was lots of time left. I reflected that what constituted lots of time for humans was something else entirely for an all-but-immortal being that had been a couple of hundreds of millions of years old back when sex had first been invented on Earth.

"An . . . audacious idea, Carlyle," Ortega said. "Moving planets around to order . . ."

"We've known as a species that we were going to have to do stuff like that someday," I replied. "In another few hundred million or a billion years, our own sun will be getting hotter and brighter. Unless we decide to abandon Earth entirely, we'll need to figure out how to move the planet to a cooler orbit."

Of course, a few billion years after that, the sun would expand into a red giant, engulfing the inner planets of the Solar System, then dwindle to a white dwarf barely larger than Earth herself. Unless we were real quick on the uptake, able to move Earth farther out on short notice, then move her much closer in, our homeworld would likely die.

By then, of course, if Humankind still existed in anything like a recognizable organic form, we would be firmly out among the stars, reshaping the entire Galaxy to order. Perhaps we would by that time be independent of planetary surfaces entirely.

"But you question . . . what did you say?" Kemmerer said. "Our political will?"

"Compared to the Deep," I said, "humans are mayflies. Ephemera. While we're waiting for the technology to move whole planets to come along, we could forget all about this place."

I wasn't claiming that humans were either callous or forgetful, or anything like that. But civilizations do not last forever, no more than do worlds, and each time a civilization falls, so much information is lost. That might be less of a problem now that we had colonies on other worlds, but humanity wasn't solidly established as a multiworld species yet. A bad interplanetary war with the Gykr or the Qesh, and Humankind could easily find itself back to chipping flints among the crumbling ruins of New York or Singapore or, looking out-system, Hope, out on Tau Ceti IV.

"Well, our problem at the moment," Summerlee said, "is these folks. Mr. Walthers, if you please?"

A vid image came up on the viewall behind her, called up by her exec. A squat, angular, flat-topped structure, startlingly black against the surrounding icescape, appeared in the middle distance. A Gykr ship hovered above the building-ugly, complicated, looking something like a tailless stingray with the wings cocked downward at a sharp angle. A column of air beneath the ship shimmered with unknown energies as the vessel held its position against gusting westerly winds.

"The Gykr commander has given us one local year to pack up and move out," Summerlee said. "Any agreement we have with HM2 Carlyle's Deep will be entirely contingent on whether we can maintain a presence on this world . . . or whether the Gykr will be taking over from us completely."