Part 4 (1/2)

MARCH.

1.

The pinnacle of Mauna Kea stands a full mile above a deck of marshmallow clouds that at sunset turn salmon pink. In late afternoon the sun seems to lower into a softly burning plain that stretches to the horizons. When the volcanoes that built the island belch, the underbellies of the clouds take on a devilish cast where they hover over the seethe of lava. Beneath these, black chunks of razor-sharp, cooled lava render the landscape stark, brooding, and ominous. Nature here seems blunt, brutal, and remorseless.

Yet above all this churn, three hundred tons of gleaming steel and gla.s.s pirouette as gracefully as-and far more precisely than-any ballerina. No dancer has ever been required to set herself to within a tiny fraction of a millimeter.

Once in position, the biggest optical telescope in the world then commands the two jaws of the covering hatches to yawn, their slow grind echoing as the 'scope drinks the first light of evening. Here is where the best and brightest come to find the farthest and dimmest. That Hawaii is the most isolated landma.s.s on Earth with the highest pinnacle gives it an advantage in the steadiness of its air. The flat ocean keeps the air stably warm over the islands. Air's usual small flutters cause stars to dance like s.h.i.+ny pennies seen at the bottom of a swimming pool. Over the peak of Mauna Kea air flows more smoothly than above any other high site in the world. The trade winds blow steady and level far beneath the realm of the telescopes.

These conditions drew astronomers, the only major life-form at this height. Up a road left deliberately rough they brought their white observing pods, immaculate domes like enormous pale mushrooms. The venerable twin Keck telescopes had ruled over this realm since their construction in the 1990s, though they were no longer the largest of their breed. An even larger dome stood in the distance, but Benjamin thought the Kecks were the more beautiful. With two thirty-three-foot mirrors made from thirty-six segments, each such light-bucket was separately movable, swiveling in an echo to the dance of the heavens above. The two mirrors were in tubes eight stories tall, each floating so precisely on oil bearings that a single hand could move them.

Not that such maneuvers were left to mere human means. Elaborate systems guided these tubes, for the human mind operating at 13,800 feet quickly lost its edge. That was why Benjamin seldom came to this height, yet today, on a whim, he had driven up. To clear his head, he had explained to others, whereas the alt.i.tude had the opposite effect. He gasped for air after even a modest climb. Pointless, really, to think that he could mull over an idea up here, where his brain was losing cells every moment to oxygen starvation.

But today there was something about the perspective, in the slanted rays of late afternoon, that seemed to fit the scale of the idea he was carrying. Intelligence and technology ruled these barren heights. Against the cruel powers of vulcanism, which had shaped the islands, mere men had set up here a citadel of intricate artifice, dedicated to pure knowledge and the expansion of horizons. In the face of the world's raw rub, and especially whenever he allowed himself to truly think about what was coming for Channing, the view from this majestic height was enn.o.bling.

Right now, he needed that. He drank it in.

If life could work its wonder upon so hostile a place, what other forbidding sites in the universe could play host to mentality? The 'scopes around him were preparing for the coming night, to chip away at answers to such questions. Eternal questions-until now.

Then his portable phone rang, dragging him back into the momentary world. It was a double ring, one of the codes they had introduced at the Center to get priority attention.

Well, it was about time, anyway. His walk up here had left him panting and somehow had clarified his resolve.

On his way down, he distracted himself by trying to find the FM station that played rock from the decade when you cared about it-the working definition of the Good Old Days.

Channing had insisted on being there when he presented his idea. Br.i.m.m.i.n.g now with resolve, he called her on the way down. She sounded quite cheery, her tone lifting at the end of sentences, a good sign. He had become fairly good at detecting when she was covering up. So when she came into the seminar room, he was startled at the drawn gray pallor of her face. Plainly it had cost her considerably to come up to the Center for this, a drive of several miles in the usual clogged traffic on narrow two-lane blacktop.

Above the gray cast her eyes sparkled with an energy that was intellectual, not physical-all that seemed capable of driving her now. He felt a pang of guilt; he should have driven home and picked her up. In fact, he had offered to, but she had shrugged it off, saying that she wanted to do some shopping later, anyway. This now looked completely implausible; he doubted that she would have the energy. But then, she had surprised him before with her desire to still visit dress shops, searching for just the right little item that would ”cover the damage,” as she put it. He embraced her gingerly, felt an answering throb in her body. Or at least he hoped it meant that, and was not one of the tremors he sometimes felt pa.s.s through her while she was asleep in bed, like an impersonal ocean wave bearing all before it.

He had decided to limit this to the usual four people, plus Victoria Martinez. If he proved utterly wrong, which he had to admit was quite probable, at least the number of witnesses to his embarra.s.sment would be manageable.

He got Channing a cup of tea and she took three of her pills along with it. By then the other three were gathered around the seminar table and he began, trying not to seem unsure, though he was.

”How many bursts from the intruder, this 'X-1' object, have we recorded so far, Amy?” He knew, of course, but like a lawyer in a courtroom, a seminar speaker should never ask a question whose answer was not readily at hand.

”Seven.” She held out the trace printouts and he waved them aside.

”Far too many. That's my argument in a nutsh.e.l.l.” Benjamin had wanted to create a dramatic effect, but saw instantly that this was too much of a jump. Victoria and Amy looked puzzled, Channing startled. He would have to be more orderly, he saw; one of his many speaking faults was a tendency to get ahead of himself. A closed mouth gathers no feet A closed mouth gathers no feet.

Kingsley frowned, his lips drawn into a thin skeptical line. ”Since we don't know the mechanism...”

”But we all have one in mind, don't we?” Channing chimed in. ”The energetic intruder smas.h.i.+ng into iceteroids.”

”Haven't heard that term before. Ice asteroids, is it?” Kingsley said amiably as he turned toward her, his face quickly changing to solicitous concern, voice filling with warmth. ”True enough, I had been making a few calculations a.s.suming that-”

”And they work out, don't they?” Benjamin said. ”Order of magnitude, anyway.”

Kingsley said, ”I can get the gamma rays, all right. It's the radio tail I'm having trouble with. How does it form?”

Amy said, ”Can't it be made pretty much the way galactic jets do?”

Benjamin was bemused by this, for he had not known Amy to venture into that realm of astrophysics. Apparently, like the rest of them, she had been doing a lot of homework. He nodded. ”It could. We can get to that. But let's stick to my main point. How often should should we see a burst, if the iceteroid idea is right?” we see a burst, if the iceteroid idea is right?”

”Depends on the thing's speed,” Kingsley said.

”Which we know from the Doppler s.h.i.+fts to be about a hundredth of the speed of light,” Amy said. ”I just finished pulling that number out of the data. The spectral fields were sorta messed up, plenty of broad lines, a real jungle.”

”Before we get to my reasoning, let's hear Amy's results.” She should have her chance to s.h.i.+ne She should have her chance to s.h.i.+ne, he thought, and then I can get a fresh start myself and then I can get a fresh start myself. She got up with a few viewgraphs, blus.h.i.+ng becomingly.

If the entire solar system, including dim Pluto, were reduced to the size of a human fingertip, the bulk of the Oort cloud of iceb.a.l.l.s would lie ten yards away from that finger. s.p.a.ce was indeed vast-and empty. But contrary to their first guesses, the intruder was not so far away. Amy had located it pretty decisively by timing the movements of bright parts of the radio tail and then making plausible arguments about how fast such radio-emitting plasma b.a.l.l.s could move. She had showed that the intruder was only a bit beyond the distance of Pluto from the sun, or forty times the Earth-sun distance. A cometary nucleus would take years to fall inward 41 Astronomical Units, but this thing was moving much faster.

”Good work, yes,” Kingsley said. He then offered his own reprise of her results-”to see if I've gotten it straight.”

Benjamin noted how Kingsley often used the flattering conversational manner of beginning his next sentence by repeating another's words, peppering his talk with references to others' contributions and generally seeming modest. It paid off; scientists were stingy with praise and a few strokes worked wonders on their mood. After thras.h.i.+ng through the data a bit more, everyone present seemed settled.

The intruder was about 50 Astronomical Units out, somewhat beyond the range of Pluto's...o...b..t. It was coming in at about a thirty-degree angle with respect to the plane the planets...o...b..ted in, the ecliptic. As Channing put it, ”The thing's pretty close-and closing fast.”

They all looked at each other. Unspoken was their growing sense of strangeness.

Now it was his turn. Benjamin began writing on the blackboard. Style mattered in bringing forth an argument, and he set the stage with numbers, bringing out the underlying contradiction.

The belt of iceteroids just beyond Pluto had been first imagined by Gerard Kuiper at the University of Chicago in the 1950s. The intruder could be hitting those. Little was known of them, despite their being much closer than the larger swarm in the Oort cloud farther out.

Benjamin drew out the point carefully. Models of the Kuiper Belt showed that the icy chunks were on average an Astronomical Unit apart-quite thinly spread. Typically they were a kilometer or two in size, about the same size as the apparent core dimension of the intruder, as seen in visible light.

”A coincidence, of course, their being about the same size,” Benjamin said. ”They can't be the same kind of thing. Point is, the odds of hitting an iceteroid in all that s.p.a.ce are tiny.” He followed with two viewgraphs giving the statistical argument, thick lines of calculations.

”If it's randomly hitting obstructions, then even at its colossal speed”-he paused to emphasize-”nearly a hundredth the speed of light!-then it would not strike one in a million years.”

Gasps. They saw the point; a bullet fired into a light snowstorm had a far better chance of hitting a snowflake.

Kingsley looked up from scribbling in his leatherbound notebook, its ornate binding his only affectation. ”In fact, it should take this intruder at least a day to fly from one iceteroid to the next-at the speed Amy worked out. Something is quite seriously wrong here.”

”I believe there are two ways out”-Benjamin went on almost as if Kingsley had not spoken-”if we want to save our idea that the thing is striking iceteroids and processing their ma.s.s into highly energetic stuff. First, as Channing pointed out-”

”It's processing their ma.s.s in stages, holding some to chew later,” she said for herself. ”That would mean it can somehow save pieces of ice.”

”Can't imagine how,” Kingsley said laconically, looking down at his notes as if to avoid any conflict with her.

Amy said brusquely, ”Me, either. But I think I see your second idea, Ben. It's not hitting these iceteroids at random. It's aiming for the next one, using the velocity change it got from consuming the last one.”

Benjamin nodded. There it was, a clear leap into the unknown. Much better to have Amy make the jump. A genuinely crazy idea, however much he had tried to couch it in terms of times and distances and statistical probabilities.

”The 'stars.h.i.+p hypothesis' again,” Kingsley said incredulously. ”Keeps popping up, despite its absurdity.” This time he looked Benjamin full in the eye.