"Sure-first, that this thing has to be enormously compressed, and the only object we know in its cla.s.s of energy and power is...a black hole." She sipped her iced tea and watched his veiled surprise.

"One of..."

He was pulling it out of her, all right, but it was an amusing game. "About three times the ma.s.s of our moon."

"You derived that from the Doppler shifts from very close in to the core, I suppose?"

"Exactly. Didn't want to say so until I had more data."

"A black hole of that size is quite small, a meter or two across." He looked at her askance, skeptical.

She had looked up the theory. Primordial black holes could have been left over from the Big Bang, but there was no evidence for them. After birth, these tiny singularities in s.p.a.ce-time could have survived their habit of radiating away sprays of particles-that is, black holes were not exactly black. This radiation had been worked out by Stephen Hawking, who showed that a small hole would have survived this evaporation, from the beginning of the universe until the present, if it had at least 1015 grams of ma.s.s. This was equivalent to an asteroid a hundred meters in radius. grams of ma.s.s. This was equivalent to an asteroid a hundred meters in radius.

The intruder, though, had a ma.s.s ten billion times greater. It had swallowed a lot, perhaps, in the last fifteen billion years as the universe ripened.

Where it came from was completely open. It could not have been born in a supernova collapse, which was the theorists' favorite recipe for making holes. Such a cataclysm would have produced a black hole of ma.s.s comparable to the sun. This intruder might have been built up by sucking in ma.s.s, all the way back to the Big Bang. Might. Maybe. Perhaps Might. Maybe. Perhaps...the familiar wiggle room terms that accompanied most advanced astrophysical theory, which was starved for hard data. Until now.

Kingsley was enjoying this a bit too much, so she cut to the chase. "So how's it guide itself, right? Like a fat man on skates, it should just shoot through in a straight line."

Kingsley allowed himself a smile. "I apologize for seeming to lead the conversation, but I have had the impression for several days that you know a great deal more than you are admitting."

"Being away from the scramble at the Center helps. The quiet gives me time to think."

"Particularly, to think of how this impossibility can exist."

"It's a black hole, almost certainly guiding itself with its magnetic fields. I've proved they're there, thousands of Gauss in strength, by looking in a small bit of the optical line data." There, the whole truth and nothing but. She was tired of all this precious waltzing around, as though they were all trying to get an ace journal paper out of this, or competing for a prize. She had operated under the a.s.sumption that Kingsley was, since he had quite a few prizes on his mantel already. But she now saw that he was beyond that, engaged at some different level.

"I see."

He had something to say now, she could tell, but wanted to be coaxed. "This object is not the only problem?"

"Sure, it's d.a.m.ned strange and people higher up-a h.e.l.l of a lot higher up-are going to want to control the situation. But our position is equally odd."

"I try not to think beyond the astronomy."

"Alas, I must." He got up and paced, hesitating at the vision of leafy paradise beyond the window. "Quite predictably, we will be...enlisted."

"Benjamin feels the same way, but he didn't want to say it."

"Why didn't he mention it to me today at the Center?"

"You two have your own, uh, styles. They don't match up too well."

"A very polite way to say it. Bad blood between us, going back to..."

"Yes, you and me. He suspects, but I've never told him."

"Good." Quick nods of the head, a brisk manner. "No point."

"He got some hints from 'friends' around the time of our marriage. I could tell, from the way he edged around the subject, bringing you up at odd times. Then, years later, noticing very obviously your steady rise up the ladder. A professorship at Manchester-'Not bad for his age,' he said. Then a chair at Cambridge, how he envied that! Always in the back of his mind I could feel the question...but he never asked."

"It was over, done."

"Between men like you nothing is ever really over."

"Well, it is to me." He smiled very slightly. "With you, I mean."

"I know. Me, too. But you two are always going to be compet.i.tors."

"Inevitably." She could see him draw himself up, taking a cleansing breath, shoving the personal into a pocket of his mind. "And I fear my understanding of how power works in our tiny world implies that matters shall soon change radically."

"For the worse."

He looked soberly at her and she saw that he had enjoyed this bit of verbal jousting as much as she. But not as flirting, no-as nostalgia. He was shoring up memories of better times, against a grim future.

Not that she did not do the same, she reminded herself.

Kingsley gazed at the tropical wealth and sighed. "We're all going to be kept here, close to the incoming data, and 'encouraged' to work together. Of that I am sure. It's what you expect, isn't it?"

"I hadn't given it a thought."

He smiled. "Of course. You have far more important matters to attend. Quite right. I do hope I am wrong."

"Me, too..." She let the sentence trail off. His transition from the Kingsley of old to this astute observer of the corridors of power was unsettling.

"I can think of no better place to be incarcerated. Compared with my situation in Oxford, especially with the chilly winds blowing from Angelica, it is-"

"It's like paradise," she finished for him.

3.

For centuries, physics and astronomy sought the big, glamorous governing equations for phenomena that were themselves ever-more grand: larger or smaller, hotter or colder, faster or slower than the narrow, comfortable human world. But shortly after the end of the TwenCen, science-particularly astronomy, with its pricey telescopes-approached the financial turnover, where ever-larger infusions of money yielded only incrementally more insight.

The universe kept upping the fare for further erudition. The particle physicists had hit that marginal realm with their ma.s.sive accelerators. Now science increasingly shifted from the fundamental equations to discovering what emerged from those equations in the real, complex world.

One faction among scientists decried this turning to more applied problems. In their vision, physics resembled Latin-an important canon, essential for advanced work and kept alive by small bands of devoted advocates. This view failed to carry the day among those who gave funding. Applied problems had become the mainstream of physics and even astronomy, making the twenty-first century a more practical place, especially when compared with the great cathedrals of knowledge erected in the TwenCen, soaring to grand heights from the base of great theories.

Astronomers, with so many new observing windows thrown open upon the universe, kept busy scrutinizing the zoo of objects available at ever-finer resolutions. Those who interpreted the observations evolved new approaches. Theorists now used pencil and paper in a blend with vast computer programs, asking questions with whatever tool seemed best.

Luckily, such intellectual armament proved to be the best for use against the problem of the intruder. Channing's discovery of high magnetic fields in the hottest, most luminous region of the object was the crucial fact that opened a rich realm of informed speculation.

Benjamin was particularly happy with the importance of magnetic fields. His doctoral thesis had focused on magnetic forces in galactic jets, and this thing definitely had a jet whose twists and filigrees the radio astronomers were enthusiastically mapping. They sent new charts daily.

Benjamin threw himself into the work, using a combination of imagination and rigorous computer programs. He was pleased to find that some of his h.o.a.ry old methods were quite germane to this problem. It helped him keep up with Kingsley's darting skills at a.n.a.lysis. They had offices near each other and their meetings were contests between the speed of Kingsley's elegant fountain pen and Benjamin's custom keyboard.

Benjamin felt himself renewed. Like many scientists, he could trace his lifelong fascination with the natural world to a key, trigger moment. His father had showed him how a magnet always knew which way was north and explained it by saying the needle was forced to line up with the magnetic field. But he could not see or feel this field, so that meant there were invisible real things in the world, less substantial than air but able to act on iron across many miles.

This clue that something deeply mysterious lay behind the everyday world was a revelation and a source of quiet, persistent excitement, a note that had sounded happily throughout his life. Such excitements of the mind had come less often in the last decade as he felt his powers ebbing. In comparison with the bright postdocs who pa.s.sed through the Center, he had felt slow to catch on to the latest currents. Now fashion, thanks to the intruder, had returned to his home turf.

"Magnetic fields act like rubber bands; it takes work to stretch or bend them," he said to several staff members who were a.s.sembled to talk, the usual crowd plus Kingsley and a few new ones. Even for informal talks, the crowd kept growing as data came in.

A newer staff woman who worked in another area was visibly struggling to keep up with the flood of ideas. "Those are the lines of force?" she asked, and he refrained from correcting. In his astrophysics textbook, he had once deliberately used that misleading phrase, then added a footnote that said: The magnetic field lines are often called "lines of force." They are not. In fact, any forces exerted by the field are perpendicular to the fields themselves. The misnomer is perpetuated here to prepare the student for the treacheries of his profession The magnetic field lines are often called "lines of force." They are not. In fact, any forces exerted by the field are perpendicular to the fields themselves. The misnomer is perpetuated here to prepare the student for the treacheries of his profession. A little prissy, maybe, and he could see this was not the time for such academic hair-splitting.

"That's exactly the point," Kingsley said. He had been sitting at the back of the seminar room, brooding, but now his voice was filled with vigor. "The intruder is exerting forces on itself by ejecting matter through its jet. Changing velocity, in a systematic way."

"How can you tell?" the woman asked. Benjamin smiled. She was unused to Kingsley's style of drawing the right questions from his audience, so that instead of lecturing people, he seemed to be merely answering them as they peppered him with their doubts. And doing it a bit serenely, too. The Cambridge touch.

Kingsley came forward and put a plastic sheet on the overhead projector. "I used these radio observations. By calculating the momentum delivered in each jet plume, I could find where the intruder was headed next, as a reaction to the matter it ejected. Here-"

The sly b.a.s.t.a.r.d's even got viewgraphs all ready, Benjamin thought admiringly, despite himself. Playing us like a G.o.dd.a.m.n violin Playing us like a G.o.dd.a.m.n violin.

The trajectory displayed was a jagged series of straight lines that nonetheless swooped inward along a persistent curve. No one had plotted these data in three dimensions yet and Benjamin saw that they had all been guilty of staying too close to the data. Kingsley stood silently, letting them digest the implication.

Benjamin jumped in. "The intruder is following a curve into the solar system. And it's finding iceteroids still, even though it's closer in than Pluto now."

"My esteemed colleague has stolen my points," Kingsley said with a stagy smile, though Benjamin knew this was exactly what he had wanted.

"It's guided," a postdoc said.

"It's guiding guiding, I think, is the point," Kingsley said.

This provoked a rustle. If Dart had gone over to the "starship hypothesis," there were huge implications.

"Targets of opportunity," Benjamin said, not wanting to get into a broader discussion. "Every time it makes a course correction, it's headed for the nearest iceteroid that will help it follow this smooth path."

"But, my G.o.d," one of the staff said, "that would mean it can find chunks of ice and rock just a few hours' flying time away-"

"Some of them only a few tens of meters across, to judge by the variations in jet luminosity we detect-" another voice called out.

"And it can then fly unerringly to its next"-Kingsley paused just enough-"prey."

A long silence. "Where's that curve go?" a staffer whispered.

"Jupiter," Kingsley said simply.

Gasps.

"And quite quickly."

"That was an admirable result," Benjamin had to say to Kingsley. They were on their way a short while later, called to Victoria Martinez's office. "You must've spent a lot of time on it."

"I had help. Called in various...o...b..tal specialists, got some computer help-"

Victoria Martinez came into her office with a tall well-dressed man. "Sorry I was late, gentlemen. Mr. Arno has just arrived."

Handshakes all round, Benjamin wondering who this was. Not an astronomer, he was fairly sure; something about the eyes. He had little time to wonder. Arno sat on the edge of Martinez's desk, as if he owned the room. Martinez did not seem to mind, and instead settled into her own high-backed chair with an expression of hovering interest, an air of deference. Arno took the time to adjust the seams in his pressed light gray Mancetti suit, which went well with his blue and red tie based on a j.a.panese woodprint. An undefinable air of presence and power came across in the way he looked directly at Benjamin.

"I'm from the U Agency," he said, as if this banished all doubt. "We've been tracking your results here and think it's time to move."

"U Agency? Ubiquitous?"

Arno frowned at this joke, but then he managed a mirthless smile and said, "I'll have to remember that one."

Martinez's eyes widened slightly in alarm. This was a manager from the big time, her expression conveyed, not the sort given to minor banter. Arno waited just one beat for this to sink in and said, "No, we are an emergency arm of your government. I've been in touch with Dr. Dart here, and others, and we felt it was time to get some control of the situation. That means bringing you into the loop-in fact, everybody working here."

Benjamin had heard vague talk of a consolidated arm, usually called in to apply leverage in international crises. Arno must represent such shadowy forces. Benjamin paid little attention to the always-precarious balance of forces in the big power arena. The United States was wearying of being the perpetual fallback stabilizer, especially since the Mideast equilibrium had dissolved into ultranationalist and water rights issues. He knew the country was a.s.suming more imperial modes, but cared little for the details. "What 'loop'-"

"Perhaps I can make this easier," Kingsley said smoothly. "I've been worried that this is moving too fast for us, and media attention is about to descend. Better to have it handled by people who can impose controls when needed."

Benjamin turned from Arno and shot back at Kingsley, "And what's that mean?"

"You see the implications of my trajectory a.n.a.lysis. It's intelligent intelligent-and hugely powerful. At the moment, it's headed toward Jupiter, but that, too, could change."

"Anything commanding those power levels is almost inconceivably dangerous," Martinez put in.

"Your authority to do this?" Benjamin asked.

"Direct from the White House," Arno said with casual a.s.surance. He straightened the cuff on his long-sleeved shirt.

"The Science Adviser has been informed?" Benjamin persisted.

"Of course. Kingsley's reports came up through her."

Benjamin glanced at Kingsley and realized he had been played for a fool for the last few weeks. "I don't think I follow-"

"Look, this is presidential," Arno said, as if explaining to a child. "The U Agency has to run the show here. It's in your own interests. We'll handle the connections to the top and to outside-the media. You guys will be free to do your research. This Center will, from now on, be devoted entirely to coordinating international intelligence."

Benjamin tried not to let himself be put off by Arno's curt, aggressive style, which he recognized from his occasional dealings with other wings of government. Still, this guy was over the top. "U Agency people, then-"

"Will work closely with yours. We'll filter everything that goes in or out."

"How do you expect us to do research with you peering over our shoulders?"

"Just bring me the results. I'm a conduit, that's all. Believe me, we've got some able minds working for us. Our people will be, well, colleagues."

Benjamin was still trying to comprehend this sudden swerve. He had come into Martinez's office expecting a friendly discussion of how to deal with the growing circle of those who knew of the intruder. He should have realized that Kingsley was at his charismatic best when he sailed before prevailing political winds, well before others sensed them. Why hadn't he seen that Kingsley fit in with the U Agency style-and that something like this was inevitable? The astronomy of it had captivated him, blinded him.

Or so went his rationale later. Arno had ended with a warm handshake and an ingratiating, obviously phony smile, the sort of expression Benjamin always suspected people of rehearsing in front of mirrors at home. But that was merely cosmetic. Arno's staff began arriving within minutes, and he knew at a glance what was in store. The U personnel dressed alike, severe and stark in their dark slacks, jackets, and off-white shirts. At least they did not wear ties. The Center staff astronomers were Hawaiian hip, in shorts and gaudy flowered shirts and thongs.