The Killing Star

To Walter Lord and Arthur C. Clarke,
our literary fathers.

I

Punctuated Equilibrium

And there fell upon men a great hail out of heaven...

—Revelation

1

Spring, A.D. 2076

For those few who lived to look back, the most fearsome deaths were the quickest. Those who did not survive the first human contact with the Intruders were alive in one moment, the billions of them—happy or unhappy, seeking new loves, leaving old loves behind, or choosing to be alone, building toward small dreams, large dreams, or having no dreams at all—and then, over an entire hemisphere of Earth, their consciousness dissolved, as if they had been the dream of something alien suddenly awakening.

The first ship came from the direction of Sagittarius. It came with fire in its belly and venom in its mind. It was an old ship, without a crew. Only machines, small and crablike, stirred within its ceramic rigging. It came with antihydrogen tanks nearly empty; but this did not matter. It was never meant to decelerate into any solar orbit or to voyage home. At 92 percent of light speed, the ship slipped through the heliopause, one light-day from the Sun, with an easy stealth, trailing only dead silence across the entire electromagnetic spectrum, until it was too late for it to be noticed. Long before reaching heliopause, it had calved four times, sending large pieces of itself toward Mars, Earth, the Moon, and Mercury. These components zeroed in on the signatures of an electronic civilization, whose radio and photonic emissions outshone even the Sun on certain frequencies, as clear and easy to follow as the sweep of a lighthouse beam.

From the ship’s swift perspective, all the heavens were compressed into a mighty dome, with the stars astern pulled into its forward view. It moved with a velocity that aged it at only one third the rate of the rest of the universe. All the energy put into achieving that velocity had transformed the Intruder into a kinetic storage device of nightmarish design. If it struck a world, every gram of the vessel’s substance would be received by that world as the target in a linear accelerator receives a spray of relativistic buckshot. Someone, somewhere, had built and was putting to use a relativistic bomb—a giant, roving atom smasher aimed at worlds.

Cold, cheerless, and determined, the ship knew itself and its purpose. It calved again—this time into two halves. One half kept what was left of the antihydrogen fuel and began to brake just enough to insure its arrival at Uranus’s small moon, Miranda, only a few hours behind the leading half, where it would strike the opposite hemisphere, guaranteeing a complete kill.

As the leading half dipped into the plane of the solar system, it encountered increasing numbers of dust particles in its shields. They ionized harmlessly ahead of the ship, blushing faint radio waves that would be detectable, if anyone on Miranda happened to be listening. The gamma ray shine of the decelerating half was also detectable, but it made no difference. One of the iron rules of relativistic bombardment was that if you could see something approaching at 92 percent of light speed, it was never where you saw it when you saw it, but was practically upon you.