Across the Sea of Suns

by Gregory Benford

  God this is really dog work, measuring this and analyzing that, all for the astro types the banded planet coming in from the left Yeah when you think about it what difference does it make, they’re summing the same data base back Earthside vast and yellow Keep totting it up, you never know a sprinkling of light in the plane of rotation Okay okay God Nigel just ’cause you’re team head doesn’t mean you can’t kid around a points of brilliance, some white and others ruddy with the reflected glow of the giant world Yeah I know her the probe swooping in for a boosting rendezvous Works in agro I think, bunks over in P4 on a timed flyby of two moons Not a looker but I hear falling powerless Ol Aarons said, Buck teeth? She could eat an apple through a tennis racket an’ the whole crowd they sipping of the stellar winds and calibrating particle energies, plasma density, UV flux Lavera you’re falling behind now closing on the first moon Funny getting a lot of backscattered light from the rotation plane an ice disk probably it’s pretty cold this far out grids deploying, lenses swinging to face the oncoming pocked and speckled face Hey I’ve resolved that so-called ice disk it’s not grains at all it’s a long string of stuff, pretty evenly spaced like beads on a string, pearls really ‘cause they’re pretty white an’ the radar says they’re smooth, no backscatter in the centimeter wavelengths deep rutted valleys cast long shadows at the blue terminator Lot of little sources in the plane, but only out from this moon, I mean there aren’t any farther in a crust of ice streaked black Probe’s passing close to one of ’em in few minutes no craters First flash looks like some structure kinda oblong must be an asteroid or maybe a broken-up moon tidal forces maybe pulled it apart and left all this crap drifting in toward the primary a gray dot of light like the others swelling I should think not elongated Yeah why? two blobs of lighter gray separate from the central image Why should debris of that type fetch up against this one moon? Seems some would get by it the two dollops now resolving into circles Damn funny formation the angle shifts as the probe moves, coming closer, focusing, and abruptly a brilliant flare burns in the field of view Whazzat so fast so that the probe stops down the input, applying polarizers and filters It’s reflection, reflected light from Wolf 359 until its motion carries it beyond and the light ebbs and it can see better the tiny control cabin at the exact point between the two huge sun sails Must be using them to get some push and behind it the dark mass of clotted ices and the restraining webbing that fixes this cargo in place Launching out from that moon, you think? the sails patiently catching the red photons of the distant sun and tilting so that the momentum they impart pushes the dusky ice gently out from the gas giant Lavera take a line of sight on these things, work out their trajectory assuming for simplicity that something’s putting them out at regular intervals from that moon for decades until the gravitional tug of the planet is balanced by the pull of the wan red star Yeah they’re winding out all-right, nice little spiral distant motes spread in a broad smooth curve Only it stops farther out and they kinda bunch up as they hesitate and then empty their small fuel reserves through low-thrust nozzles, outgassing vapor that has boiled from the surface of the ices they carry an’ looks like they peel off an’ come back in movin’ pretty slow though this time moving not in spirals but in long, low-energy hyperbolic orbits an’ they start spreadin’ out pickin’ up speed I guess plunging down in the grip of the banded orange-yellow world, past the roiling brown bands at a higher speed than they have ever known, correcting their courses under instructions from the distant ancient parent moon I’m losin’ them after that, guess they string out gettin’ too far away to pick them up but they’re not gravitationally bound anymore I can tell that falling free at last toward the inner world which began it all millions of years before I should think with that little thrust the voyage carrying valuable ice which will intersect the small planet’s orbit and plunge into the wisp of atmosphere Right Nigel I make it five, six hunnert years to get into the inner system looks like that terratype is the target, too, or close to it so that the sky begins to glow with a shower of small meteors, shedding vapor as they fall free All this just to move chunks of ice? the icebergs splitting into showers that sparkle in the night sky above an arid plain I make the rate maybe one a month the sky warms an’ at that rate it’d take forty forevers to sock in an ocean soft, moist breezes stir beneath a dim but perpetual sun Agreed, but that is precisely how long they may very well have the icebergs coming to aid a biosphere which is now long dead but can with the steady pressure of chemical laws begin again What’s more, you’ll note there were lakes back on that forlorn little speck the probe pivots and below a stark face rushes by Point is, what’s sending them? plains cut in rectangular blocks, antlike black forms moving on designated roads to pick up their loads of ice and rock and return to a central smudge of tread-churned brown Something that can use solar energy, must be to last this long vast shining screens, a sprawl of manufacturing plants, all ice-crusted The machines must be able to repair themselves by the same argument, build new ones like themselves when needed, guide the ones in flight slow and steady, chipping at blue-veined mountains, loading electromagnetic slingshot launchers Who’d set all this running? I mean what’s the point of the ice has wrenched and split under the changing forces which came as weight was removed and the moon is cracked, faulted, and pitted as it is eaten Whatever or whoever lived back there, on that planet, millions of years ago, and set this in motion the machines keep on, gnawing and dying and being replaced But they’re gone Nigel, the biosphere’s wiped the probe swings by the ice moon and arrows past the gas giant, changing its momentum to boost outward for the next star hanging a dozen light-years away Surely but those black specks don’t know that the ramscoop cuts in So they’re running on? Christ doesn’t make sense when whatever finished off a whole goddamn bio-sphere came through, I mean why not just knock off these little rumbling, the magnetic fields reach out and grasp ions to flavor the new fusion fire I’ll fancy we can’t say, from this trifling investment of fact but mind, there was a Watcher back there round that planet the gas giant is blurred in its exhaust Well might have been we didn’t get a good look an’ Landon says he doesn’t see that much similarity leaving Good enough, but how’s he to explain the other fact? the dead worlds far behind, the moon stirring What fact? I don’t outward That there was no Watcher round that moon

  THREE

  In 2045 Lancer had paused in its steady one-g acceleration out from Earth, long enough to deploy the largest telescope ever conceived. It was a gossamer-thin array of optical and microwave receivers, flung out like a fishing net. Nigel had worked for days helping to dispatch the sensors in the right order, avoiding the heavy work for fear it would show a spike of strain on his metabolic report.

  Men and women cast their net to capture photons; the telescope itself was provided by the distant, white bright speck of their sun. Space is not flat, like the marble Italian foyers Galileo imagined, where his gliding blocks went on forever in ideal experiments carried out free of friction. The mass of those hypothetical blocks would stretch space itself, warp the obliging flat plane. Mass tugs at light. Forced into a curve, light will focus. The symmetry of three dimensions in turn shaped any sizable mass into a sphere, perfect for a lens. Each star was a huge refractor, a gravitational lens.

  Lancer dropped sensor nets, starting three light-days out from Sol. The nets gathered in photons like a spring harvest, compiling sharp images of distant stars, resolving detail a mere ten kilometers across. For each star the focal distance from the sun was different, and so the webs had to tack against the wind of particles blowing out from the sun, using the magnetic fields beyond the planets to trim and guide their long scalloping orbits.

  Lancer rumbled and forked a pure, blue-hot plasma arc, and pulled away from the gravitational lens that was its native star, leaving the colossal telescope behind. It would be six years before the first dim images would be finished. Ever since the sun had formed from infalling dust, pictures from worlds hundreds of parsecs away had been forming in the s
paces far beyond the planets. Those focused stories, now forever lost, had run their courses on the gigantic hypothetical screen, the imaging plane. Through billions of years, until this moment, there had been no one in the theater to watch them.

  Lancer’s destination was a mild red dot known in the catalog as Ross 128. It was the sun’s twelfth nearest neighbor, an unremarkable M-5 star. Toward the end of the twentieth century some X-ray astronomers had studied it briefly, comparing the hard radiation from it with our Sun’s. It was a little more active, but once the solar physicists on a NASA grant had milked it, they forgot it. So did everybody else.

  The gravitational lens array showed a full-sized solar system, though: five gas giants plus two Earth-sized worlds. A robot probe had reached Ross 128 about the time Lancer went into orbit around Ra. Something had silenced its transmissions as it entered the system.

  Lancer was “nearby.” It could study a system far better than any flyby could. Earthside thought that the death of the robot probe was worth a follow-up. Maybe it had smacked into a rock. Or maybe something wanted it to look that way.

  Earthside’s strategy was to accumulate-astronomical information, fast, and stir it into the pot with data on the Swarmers and Skimmers. This was a compromise reached by the important space-faring nations, totally outside the aging carcass of the United Nations. The Asian faction wanted to push colonization of the nearby stars as soon as possible. That way, humanity would be dispersed. If the Swarmer-Skimmer fleet returned and destroyed humanity’s space resources, at least the race would be already spread among the stars, and relatively invulnerable.

  The Europeans and Americans backed a pure exploratory program. Behind this was calculated advantage. The Asian economies were doing better at capitalism than the societies that had invented the notion in the first place. The Western economics were broke. If colonization started right away, the stars would belong to the short and slant-eyed.

  Lancer was ordered to investigate Ross 128, then return home. But Ra was not finished with them. After a year of acceleration, Lancer leveled out at 0.98 light speed. When it damped its fusion plume, the plasma exhaust unfurling behind it dropped in density. The thinner the plasma, the easier radio waves can get through.

  At 15:46 hours, June 11, shipboard antennas picked up an intense burst of microwave emission. It came from dead aft and lasted 73 seconds. After that, nothing.

  No look I can’t break it down further like I was telling you the data’s all over the board

  Dispersion in the pulse from all that crap we’re throwin’ behind us just plain messed up the signal

  Not from the EMs though that’s not their frequency we never got anything from ’em up at ten GHz

  Okay sure but Ted here wants to know if there’s any chance they sent it

  Who can tell Christ no info in that burst at all

  Yeah right but lookit the power man—I’d say doesn’t look like a solar flare or anything natural

  Course not, too tight a band, and a little star like Ra can’t do much better than hunnert megahertz never make it up to ten gigs and you’re right about the power no way it can be those Ems

  Ted I got the calibration on it and it’s a helluva shot of power innat burst doesn’t make sense

  Too much power yeah I mean no artificial source would put out that much it’s crazy

  Right, if you think they’re broadcasting in all directions, a spherical pulse, then it would take a bloody avalanche of power to register as much as we’re getting

  Who’s ’at on the line

  Walmsley sounds like, look Nigel, this’s just a tech-talk

  Merely sitting in, don’t pay me any mind

  Must be artificial though the burst’s so short

  This is Ted I’m sure your results are right overall but honestly gentlemen and ladies I don’t believe we can reconcile a power level like that from the EMs or anyone else it must be Ra itself some sort of occasional outburst or

  Nonsense, I say

  Well Nigel I don’t see how you can simply brush aside

  Interesting isn’t it that our exhaust plume distorts the signal enough so that we can’t read it? Decidedly convenient

  Well sure but that’s just an accident of

  In a seventy-three-second burst you can pack a lot

  If there is information content sure but who says

  Ted this is Nigel, if someone were to beam a tight-focused signal along our trajectory it would seem to have a huge power, because we’re analyzing it as though the emission was flooding out over all space, rather than being squeezed into a small angle

  Well sure I guess but natural emissions from Ra oh I see

  So this tells us somebody sent a message our way but pitched at a frequency that would get bloody well swallowed by our own exhaust so we couldn’t unscramble it

  Well okay I mean that’s an alternate hypothesis

  This is Ted give me the visual on that would you?—guess you’re right there’s no way to decode a mess like that but look Nigel I don’t buy that one I mean why would the EMs broadcast at that high frequency they can’t with their body structure and anybody who wanted to communicate would use something we could decode at least

  Quite so, if they wanted us to

  I don’t get

  We’re on a line of sight from Ra remember

  You mean if it wasn’t targeted for us at all but instead

  Right we’re on a dead straight line and Ross 128 is another point on that line

  Well we’ll take that under advisement Nigel thanks for sure yeah thanks

  “Well, I, I don’t know,” Nigel said.

  “Come now. You’re positively shy.” Nikka grinned.

  “Dead right.” He liked her in this mood, but sometimes she was, well, too much. He was shy, and quite properly so. He looked around at the neat rows of improbably tall vegetables. “Rather public for my taste.”

  Above he could see a distant figure working a wheat field on the other side of the slowly spinning cylinder. Along the axis a fleet of puffy clouds streamed, ships with a single destination. Nikka said, “Let’s go into those trees, there.”

  Obediently he followed. “Won’t we embarrass God?”

  “God? She tries to encourage this kind of thing.”

  “Um.” Nigel appreciated her cajoling him into this; it was precisely the craziness of it that would draw him out of himself for a while. They entered a stand of birch. Above, fresh clouds dispersed a blue light. The engineers had rigged mirrors and lenses to bring the exhaust flame’s fierce luminosity into the life volume, where its glow brought an irridescent warmth to the air.

  “Here,” Nikka said, and efficiently shucked her coverall. Underfoot, the earth cracked with a swelling of pseu-dospring, cradled by the microenviron mechanisms into fresh life. The pace of change was forced by fine-tuning at the molecular level. Still, as Nigel lay down he caught from afar the sodden autumnal ripeness of leaves, mingling with a crisp flavor of new shoots in the birches overhead, and underlying it all, a humid dry richness of the summer crops that blossomed across the axis, where harvesttime was soon to come. On tradition-minded Earth, one never walked amid such a cross-current of seasons.

  Kneeling, he noted that they both had begun to sweat. He licked the rivulet between her breasts and found it lukewarm, salty. He encircled her, sipped at her, traced whirlpool wisps that left spittle shimmering in her pubic hair. The faintly violet shafts from a man-made sun shifted through branches and fell across lips, lurid as slices of salmon, as he lost himself in her; seeking some deeper taste, the swollen nerves beneath the moss. His hands traced the waist that billowed downward into an hourglass, and to where the flowing body forked. This portal of curls became the crux of her Euclidean theorem, a pivot where all lines must intersect and lemmas could be learned. She seemed to tumble out of the air to him in this trimmed gravity, breathing shallowly, heart tripping. He took her with the simplicity their years allowed. He clutched her wineglass center and cu
pped her to him. By easing steps he felt her widening sense of him. He closed his eyes. A breeze stirred boughs above them. Distant machines chugged. He opened his eyes as she gripped him and abstractly he studied her eyelids, veined in wriggles of purple, and beneath, a sly smile. A slick pace came upon her and a swirl of laughter welled out. He kissed her shoulder and felt it as round as a moon. Her face snapped sideways and lifted him so that he felt her to be a craft under him, running to its own currents, something vast from the natural darkness, and in that strange gulf he leaped, and leaped again, to join her. “Oh,” she said, and then again.

  In a while he found he was on his back, solemnly studying the field tenders a kilometer away who labored upside down. She lay sprawled like a broken toy, accepting entirely the shafts like sunlight. Nigel watched a flock of chickens swim down the axis, out for their constitutional, following corn kernels. Here and there small globs fell from them. Dung, descending in straight lines. In his spinning frame the droppings curved in spirals, Newtonian whorls.

  “You’re looking contented,” Nikka murmured.

  “This was a bloody good idea.”

  “Glad you approve. I was going to ask Carlotta to come also, but she has a shift now.”

  “Just as well. She and I haven’t, well, been getting on lately.

  “I thought perhaps that was so… . Any particular reason?”

  “None I can spot. She simply seems skittish.”

  “She’s been very busy, of course.”

  “Right. I think that, sexually, we’re just not on the same wavelength any longer. Sharp and pungent while it lasted, though.” He stretched lazily and rolled in the grass. “Who was it who said that simple pleasures are the last refuge of the complex?”

  “Oscar Wilde.” Carlotta’s voice came from behind them. She approached, apparently having missed the earlier talk. Her dark hair swayed as she looked from Nigel to Nikka.