“Nicolaus, why would you want to impede the work on the shield? You’ve been at my side throughout. Can’t you see how important it is?”

“If God wishes us to be put to the fire of the sunstorm, so be it. And if He chooses to save us, so be it. For us to question His authority over us with this monstrous gesture—”

“Oh, can it,” she said irritably. “I’ve heard it all before. A Tower of Babel in space, eh? And you’re the one to bring it down. How disappointing, how banal!”

“Miriam, your mockery can’t hurt me anymore. I have found faith,” he said.

And there was the real problem, she realized.

In his conversion Nicolaus wasn’t alone. All the major faiths, sects, and cults worldwide had recorded a marked rise in conversions since June 9. You might expect a flight to God in the face of impending catastrophe—but there was a theory, still controversial and revealed to her only in confidential briefings, that increased solar activity was correlated with religious impulses in humans. The great electromagnetic energies that had washed over the planet since June 9 were, it seemed, able to work subtle changes in the complicated bioelectrical fields of a human brain, just as in power cables and computer chips.

If that was true—if the agitation of the sun had somehow led, by a long and complicated causal chain, to a lethal ideological determination in the mind of Miriam’s closest colleague to kill her—well, what an irony it would be. She said blackly, “If God exists, He must be laughing right now.”

“What did you say?”

“Never mind.” A thought struck her. “Nicolaus—where will we come down?”

He smiled coldly. “Rome,” he said.

Siobhan asked, “Can we say where this rogue planet came from?”

Not from the solar system, of course; it had been moving too fast to have been captured by the sun. Eugene displayed more of his “patched solutions,” projecting the path of his Jovian back to the distant stars. He rattled off celestial coordinates, but Siobhan stopped him and turned to Mikhail. “Can you put that into English?”

“Aquila,” Mikhail said. “It came to us out of the constellation of the eagle.” This was a constellation close to the sky’s equator; from Earth the plane of the Galaxy appeared to run through it. Mikhail said, “In fact, Professor McGorran, we know that this object must have came from the star Altair.” Altair was the brightest star in Aquila. It was some sixteen light-years from Earth.

Eugene cautioned, “Mikhail, I’m not sure we should talk about this. The projection gets fuzzy if you push it back that far. The error bars—”

Mikhail said grimly, “My boy, this is not a time for timidity. Professor, it appears that Eugene’s rogue Jovian originated in orbit around Altair. It was flung out after a series of close encounters with other planets in the system, which are visible with our planet-finder telescopes. The details are understandably sketchy, but we hope to pin them down further.”

“And,” Siobhan said, “it was hurled our way.”

Toby pulled his nose. “It seems fantastic.”

Mikhail said quickly, “The reconstruction is very reliable. It has been verified from multiple data sources using a variety of independent methods. I have checked over Eugene’s calculations myself. This is all quite authoritative.”

Bisesa listened to all this quietly, without reacting.

“Okay,” Toby said. “So a rogue planet fell into the sun. It’s an astonishing thing to happen, but not unprecedented. Remember Comet Shoemaker-Levy colliding with Jupiter in the 1990s? And—with respect—what does it have to do with Lieutenant Dutt and her theories about extraterrestrial intervention?”

Eugene snapped, “Are you such a fool that you can’t see it?”

Toby bit back, “Now look here—”

Siobhan grabbed his arm. “Just take us through it, Eugene. Step by step.”

Eugene visibly fought for patience. “Have you really no idea how unlikely this scenario is? Yes, there are rogue planets, formed independently of stars, or flung out of stellar systems. Yes, it may happen that such a planet could cross from one system to another. But it’s highly unlikely. The Galaxy is empty. To scale, the stars are like grains of sand, separated by kilometers. I estimate the chance of a planet like this coming anywhere near our solar system as being one in a hundred thousand.

“And this Jovian didn’t just approach us—it didn’t just fall near the sun—it fell directly into the sun, on a trajectory that would take it directly toward the sun’s center of mass.” He laughed, disbelieving at their incomprehension. “The odds against such a thing are absurd. No naturalistic explanation is plausible.”

Mikhail nodded. “Circumstantial, perhaps, but still … I’ve always thought Sherlock Holmes put it well. ‘When you have eliminated the impossible, whatever remains, however improbable, must be the truth.’ ”

“Somebody did this,” Toby said slowly. “That’s what you’re saying. Somebody deliberately fired a planet, a big fat Jovian, straight at our sun. We’ve been hit by a bullet from God.”

Bisesa said briskly, “Oh, I don’t think it has anything to do with God.” She stood up. “More coffee?”

“Nicolaus—your target is the Vatican?” But the destruction would be much more extensive than that. A spaceplane returning from orbit packed a lot of kinetic energy: the Eternal City would be hit by an explosion with the force of a small nuclear weapon. She had not felt like crying before, but now tears pricked her eyes: not for herself, but for the destruction that would come. “Oh, Nicolaus. What a waste. What a terrible—”

And then the bomb went off. It felt like a punch in the back.

She was still conscious, for a while. She could even breathe. The cabin had survived, and its systems were doing its best to protect her. But she could feel herself tumbling, and monstrous G-forces pushed her deep into her seat. She could hear nothing; the blast had left her deafened—not that it mattered anymore.

She was falling through the sky, she supposed, trapped in a piece of wreckage thrown out of a fireball high above Rome.

Still she felt no anger, no fear. Only sadness that she would not see the greatest job of her life through to the end. Sadness that she had had no chance to say goodbye to those she loved.

But she had been tired, she thought. So very tired. It was up to the others now.

In the last second she felt a hand creep into hers. Nicolaus’s, a last, raw human contact. She gripped it hard. Then, as the spinning worsened, she blacked out, and knew no more.

***************************

Part 4

26: Altair

The star called Altair is so far away that its light takes more than sixteen years to travel to Earth. And yet Altair is a neighbor, comparatively; only a few dozen stars lie closer to the sun.

Altair is a stable star, but more massive than the sun. Its surface, twice the temperature of Sol’s, glows white with none of the sun’s hint of yellowness, and it breathes out ten times as much energy into the faces of its scattered flock of planets.

Of those planets six are immense Jovians, all but one more massive than Jupiter. They all formed close to the parent star on looping orbits, wheeling like a flock of monstrous birds. But with time the Jovians, plucking at each other with their mighty gravitational fields, gradually migrated outward. Most of them settled into a neat clockwork array of circular orbits. Complex physical and chemical processes churned in the planets’ hot, deep interiors—and, in the tranquillity of eons, on some of those worlds life was spawned.

One planet was different, though.

This swollen monster, fifteen times more massive than Jupiter, was peculiarly unlucky in its interactions with its brethren. It was flung far out of the parent system, on a looping elliptical orbit whose farthest reach took it into the chill realm of comets. This huge orbit took millions of years to complete—and so every few megayears Altair’s huddled family of inner planets was disturbed by the rogue giant’s plummeting visits from the depths of space. Worlds that might have been Earths rolled and quivered, plucked by the rogue’s gravity. Not only that, but the rogue’s passage through Altair’s broad belts of comets and asteroids sent a heavy rain pouring into the inner system. On Altair’s worlds, dinosaur-killer impacts were the norm, falling a hundred times more frequently than on Earth.