Europa Strike (13 page)

The most far-traveled of Sam Too's iterations, however, was a very long distance indeed from Earth.

 

Alpha Centauri A II

2200 hours (Zulu)

 

Sam Too could be in several places at once, a useful trick when you were the sole intelligent being within a range of 4.3 light years.

At the moment, most of her awareness was still resident within the twenty-meter confines of the
Ad Astra
, the upper stage of an A-M drive spacecraft launched from Earth orbit ten years before. She'd completed deceleration into the system five months earlier, and spent the time since carrying out a telescopic survey of both stellar components, Alpha Centauri A and B.

So far, her discoveries on that program track mirrored perfectly the information acquired from deep solar orbit by AI 929 Farstar. Alpha Centauri had been among the 1,000-kilometer space telescope's first targets when it went online twelve years ago. Its observations of a world whose spectrum showed the distinct presence of oxygen in the atmosphere—and, therefore, of life—had determined the
Ad Astra's
destination. Subsequent observations had identified continents covered by what was almost certainly vegetation, oceans, and certain other features that demanded close-up inspection.

It would be a long time before humans could make an interstellar voyage. That Sam had made the trek was due to a number of special considerations—that she could endure for months on end accelerations that would have killed a human; that she required no bulky life-support system, recycling facilities, rotating hab modules, climate control, food, or entertainment; that she could, in fact, measure time not by the one-by-one passing of milliseconds, but by the passage of discrete events—in essence, sleeping throughout most of the voyage, unless moved to greater awareness by a scheduled event on the mission plan or by an alarm from the ship's sensors or autonomous systems. She remembered very little of the nine-year coast across the light years, save for those moments when she'd awoken to make navigational or scientific observations.

More than once, in fact, during the months before she'd been uploaded to the
Ad Astra's
computer net, she'd argued with Jack Ramsey and others of the Hans Moravec Institute design team that humans would
never
reach the stars; it made far more sense to send emissaries such as herself. The universe, she'd argued with some passion, might well belong to instrumentalities such as herself, artificial intelligences designed to make voyages that mortal beings could dream about but never make in the flesh.

Her position, of course, was weakened by the obvious fact that organic intelligences
did
make interstellar voyages—and frequently, in fact. Half a million years ago, the Builders had attempted to terraform Mars, until someone else had found and destroyed them. Just twelve thousand years ago, at the end of the last Ice Age, the An had arrived, building a colony complex on the moon and in what would one day become Mesopotamia, had built their spectacular monuments, had enslaved half a million humans and in that enslavement introduced them to civilization. And then they had been destroyed by yet
another
interstellar visitation—the
Ur-Bakar
, the Hunters of the Dawn.

As her principal designer, Jack Ramsey, had said once with considerable feeling, “Hell, it's beginning to look like Earth used to be the Grand Central Station of the Galaxy!”

Sam Too enjoyed argument, however, and frequently took hard-to-defend positions deliberately—an intellectual diversion that frequently exasperated her designers because they could never tell whether or not she was serious.

She had no one to argue with now, however. Sam was as alone as it was possible for any intelligent being to be.

Sam continued to compile data on the world she was orbiting, squirting every bit of data via laser aimed at a particularly bright star intruding on the W shape of Cassiopeia near its border with Cepheus. She already had the equivalent of hundreds of volumes; the essentials, laid out like an entry in a geographical almanac, gave a concise if dry image of the planet below.

Star: Alpha Centauri A

Stellar Class: GO; Radius: 1.05 Sol; Mass: 1.05 Sol; Luminosity: 1.45 Sol

 

Alpha Centauri A II:

Chiron

 

Physical Data

Distance from primary: mean 1.15 AU; Apasteron:

1.1728 AU; Periasteron: 1.1272 AU;

Orbital Eccentricity:.0198; Orbital Period 1.187 years (433.44 days);

Rotational Period: 19h 27m 56.25s; Diameter: 9795 km; Density: 5.512;

Planetary mass: 2.6892 × 10
²⁷
gm (0.45 Earth);

Circumference 30771.9 km;

Surface Area: 301410760.9 km
²
; Surface Gravity: 0.77 G;

Escape Velocity: 8.58 km/sec; Magnetic Field: 0.52 gauss; Axial Tilt: 8° 15“ 31.34”

 

Surface Data

Hydrosphere: 39%; Lithosphere: 61%; Desert, Arid, or Barren Terrain: 69%; Mountainous Terrain: 12%;

Forested Areas: 10%; Plain, Savannah, or Veldt: 5%;

Other: 4%; No polar ice caps or extensive glaciation evident; No appreciable seasonal snowfall save at extreme elevations; Cloud cover: Approximately 50%;

Albedo: 0.26; Mean surface referent temperature: 39° C
.

 

Atmosphere

Pressure: 515 mm Hg = .678 bar

Composition: N
₂
74.97%; O
_2'
22.43% (partial pressure O2 = 15.2%); Ar, 1.54%; H
₂
O,.1-2.1% (mean 1.0%);

CO
₂
: 466 ppm; Ne, 59.7 ppm; He, 7.87 ppm;

Other: ‹ 7 ppm

 

The facts and figures scarcely embraced a world, however. Chiron—the world, inevitably, had been named after the centaur in Greek myth who'd been the teacher of Aesclepius the Healer—was mostly desert and arid mountain, with scattered, shallow seas and vast salt flats indicating that those seas once had been larger. The atmosphere was thin, though the oxygen levels were high enough that the PPO
₂
would have allowed humans to breathe on the surface without artificial assistance. The world was scarcely inviting by human standards, however. Though slightly farther from its primary than Earth was from Sol, Chiron circled a star almost half again as bright than Earth's sun. The base temperature was 37 degrees, considerably warmer than humans liked it—though the polar regions and higher elevations were temperate, and in winter might even see a few, brief snowfalls.

And, in human terms, the scenery was spectacular. The colors were all gold and red, the result of a chlorophyll analogue that colored the vegetation in reddish and yellow hues. More heat and faster rotation than Earth meant more powerful storms. A more energetic sun, stronger magnetic field, and faster rotation meant more spectacular auroras illuminating the night. And there was always Alpha Centauri B, the second component of the double sun system, which every eighty years came within eleven astronomical units—not enough to add more than a few degrees to the planet's base temperature, but close enough to shine even in the daytime sky as a brilliant orange-white beacon, and to cast light enough at night to read by easily.

At the moment, B was approaching periastron, 35 AU out. The orange star had apparently truncated A's fledgling solar system early in its history—Alpha Centauri A possessed only three planets, the outermost a small gas giant just 1.9 AU out. Any outer worlds must have been flung into interstellar space billions of years ago by the perturbations of the dual-sun complex. B had a miniature solar system of its own as well, two worlds—a gas giant the size of Neptune, and an airless Mercurian rock.

But so much had been observed twelve years ago by Farstar and other telescopic efforts from Earth's solar system. A. What had attracted human interest in Alpha Centauri A II had been the Chironian Ruins.

They were scattered across the arid surface of the world like the salt encrustations along the shores of the dying seas—tens of thousands of square kilometers of them, remnants of cities constructed with truly cyclopean magnificence, smashed and blasted and tumbled-down, now, in an all-encompassing devastation suggesting apocalypse on a planetary scale.

Farstar and the other Sol-system telescopes had mapped large parts of those labyrinthine ruins, though that was an ongoing task that would take another century at least to complete. Those distant eyes could not peer through earth, rock, and fallen masonry, however, nor could they see through the towering thunderheads that frequently obscured the Chironian coastal regions. A closer inspection was necessary, and that was
Ad Astra'
s primary mission.

Sam Too had in one sense divided herself, her awareness, in two. The main part of her consciousness continued to reside within the
Ad Astra
as it orbited Chiron, circling the golden world once every 200 minutes.

However, she was also in close laser and radio communications contact with Oscar, one of three ranger probes carried in external cradles slung from the
Ad Astra
's spine. With the other two probes in reserve, Oscar had been deorbited hours earlier, dropped into a meteoric entry vector that had scratched white fire across the Chironian night and now, hours later, was down in the general vicinity of a particular landmark called the Needle.

While a small part of Sam Too's awareness was now resident in the computers on board Oscar, what was there was capable of only about 10
¹²
cps and was not in any way self-aware. Most of Sam remained with the
Ad Astra
, maintaining the linkage even when the spacecraft dropped below Oscar's horizon by a constellation of communications satellite strung along the ship's orbital path like beads on a string.

An important principle of sensory psychology insisted that it didn't matter how long the data input path was, whether it was the few inches of the human optic nerve leading to the brain, or a lasercom-and-relay sat connection across thousands of kilometers. Through the teleoperational link, Sam was
there
as Oscar picked its way across the rubble-strewn landscape. She could see the play of golden light across the thunderheads on the eastern horizon, as Alpha A rose in dazzling yellow splendor, feel the hot, thin breeze, hear the shriek of Oscar's jets.

Oscar floated a few meters above the ground. Once it had discarded its reentry shell, its three-meter body had unfolded into a Y-shaped framework with massive, cylindrical turbine-drive housings on pivot mounts on each upraised arm. Those drives sucked air down through the anterior vents, compressed it, heated it in tiny, gas-core fission micropiles, and blasted it out as exhaust, keeping the robotic craft hovering above the ground. Slight cantings of the drive housings together or independently sent the craft skittering across the landscape; at need, it could reach 400 kph, but at the moment it was employing just enough thrust to hover and drift slowly forward. Hatches had opened on the lower hull so that it could extend a variety of sensors and manipulators. A pair of lenses, like blackshrouded binoculars unfolding from the cusp of the Y, twisted back and forth on the end of a jointed arm, providing 3-D vision from a platform at least as agile and maneuverable as a human neck and head.

As far as Sam's remote eyes could see, the ground was covered with the shattered relics of a civilization of high order. Sam possessed downloaded memories of the Cydonian dig on Mars; this was similar, but far larger. Those structures still standing had been wind-blasted for hundreds of thousands of years, leaving them scarcely recognizable as artificial. Chipped and broken and sand-worn blocks of something like blue-white marble lay everywhere, too thickly strewn for walking to be at all easy. For millennia, the desert had been encroaching on the site, and sand dunes had claimed much of this city; eastward, toward the rising sun, a large sea had retreated, leaving a salt plain that gleamed like ice in the sunlight. Vegetation still endured within the ruins, however; something that looked like roses covered some of the rubble—Sam
did
know what a rose was—though these sprouted in masses from uncurling vines, with no leaves, and appeared to have been molded from some ruby-hued, gelatinous, extruded material, rather than grown as a cluster of petals. The red and orange blossoms here appeared to serve as photosynthesizing leaves rather than as organs of reproduction.

But the biology of Chiron could wait for another time, perhaps even for another expedition. It was the ruins that drew Sam on, and one artifact in particular.

She'd identified it from orbit, based on sharply enhanced imagery from Farstar. Her human colleagues had named it the Needle, and indeed, it looked like one—slim and silver and erect, nearly a hundred meters tall, with an opening at the slender, rounded base like a needle's eye. It rose from a kind of dais at the east edge of a broad, wide stone-tiled area called the Plaza.

This landmark, too, had been seen through Farstar's long-range vision, though not in useful detail. As big as the Square of St. Peter's in Rome, the Plaza was circular, with openings in its walls facing east, toward the Needle, and west, toward a structure known simply as the Pyramid. Once, Sam thought, this might have been a park or tame forest of a sort; the Plaza's center was open ground, rather than pavement, and there were still “roses” and a profusion of other gold-hued vegetation growing there.

Around the perimeter of the Plaza, however, were the statues that had captured human interest in the first place. There were eighty-one of them in all, with perhaps a third still standing. The others had fallen long ago, some more or less intact, others smashed into gleaming, broken-crystal shards.