Nikka tapped her wrist and the wall screen clicked on. She silenced Alex’s voice-over explanations and enlarged the map. Nigel peered at the round image. The Isis disk was a spaghetti scramble of contour lines.
“Planetary acne,” he said.
Nikka said, “Looks like a river valley system, there.”
“Couldn’t be. Trick of the eye, probably. This isn’t radar, remember. They’re picking up the Isis transmissions.”
“How can it come from all over the planet’?”
He squinted. “It can’t. The simple, efficient way to send across interstellar distances is with one fixed antenna.”
“Yes …” She combed back her sleek black hair with her fingers. “Or so we think.”
“Electromagnetic waves are culture-independent. Makes no sense to use lots of antennas.”
He tapped into the interactive-mode discussion, still lying in bed. No interesting ideas surfaced. “Wait’ll we’re closer,” he said.
Nikka dialed the map to max scale. “I still say it looks like a river valley.”
THREE
Isis was a red world. Mars-tinged, Nigel thought, staring down at it. But rich with air, cloud-choked.
One warm face forever pinned toward Ra, the other staring blank and frozen into the eternal cold: tide-locked. In the immemorial night the land groaned beneath vast blue glaciers. Half a planet, capped in ice.
Winds from the twilight fed the great, slumbering, white-crusted mountains, bringing breaths of fresh moisture. At the eternal dawn line where dim pink light licked, icebergs calved into a red ocean. The sea circled Isis, pole to pole, separating ice and land. It was pink and glinting, scratched by winds, dotted with orange-yellow clouds.
More sunward still, broad fans of waves battered at the base of steep, flinty chasms. The sea clawed at the rising ramparts of the one vast stained brown continent.
Fingers of water thrust inland, toward Ra. River valleys carved the gray granite, as if clutching the world’s face, to force it toward the fire. Fingers: poking at the Eye.
Channel #11: “Yeah, that pattern, what’d I say, fits the theory. Perfect stress pattern there, you can see the normal faulting and graben at the poles—”
Channel #20: “Jess a sec, theh ah no poles at all, an’. if unnerstan your calc, your equilibrium is wrong from step one—”
Channel #5: “—Jeezus, check the chem inventory down there, I’d—”
Channel #11: “No, I’ve got a whole continuum of theoretical equilibria I can use and this case fits in; it all works if we assume Isis formed rotating, with a bulge at the equator, and then when Ra spun it down that released the centrifugal energy, so Isis tried to readjust its surface to get rid of that pot belly, and you get fracturing in a global pattern—”
Channel #5: “—too much absorption in those oceans, an’ some odd lines, lookit those spikes around 5480 angstroms, that’s not—”
Channel #18: “Funny, the lakes in those highlands, partway out from the Eye, they’re blue, but the ocean is pink. I guess whatever—”
Channel #5: “That’s fresh rainfall up there in the mountain passes, melted snow, it should look blue—”
Channel #11: “—that leaves the equator free, see, so thrust faults split the dome pattern, and the energy got released toward the rim—”
Channel #20: “Okay, no poles, your calc stipped a bound’ry layer an’ thahs what makes the calc work out. Those headwalls in the rim gouge pattern, see ’at? I guess they prove some kinda big crust relaxation when it slowed down, started a whole big tectonic process—
Channel #5: “—the 5480 structure is just backscatter from the hills, must be, Nigel, ’cause that’s the iron silicate group clear as day, damn muddy day down there though, an’—”
Channel #11: “—you get these compression networks that give those wrench faults, or lateral faults, I can see them on this IR blowup, here, lots of rifting, a whole morphology set up when the planet spun down—”
Channel #3: “—but then what’re those ghastly spikes dead center of the polarization pattern, eh? You’re surely not going to ask me to believe a mud flat is giving us those spikes, are you? Scarcely. The sea is giving us those, and it has to have iron oxides to do that and give sufficient line strength—
Channel #18: “Blue lakes means that whatever makes the seas red doesn’t operate at high altitudes—”
Channel #5: “That’s garbage, there can’t be a height effect with that kind of gentle gradient, it just won’t support a—”
Channel #18: “Okay, then it takes time to make the chemistry go, so by the time the rainfall has run down to the lowlands something’s—”
Channel #29: “—he’d got that wrong twice, Christ, so I kinda shrug and mutter, nothing wrong with having nothing to say, sure but try not to say it out loud, and the sonabitch went straight to Gulvinch about it then—”
Channel #20: “— intensifahs all ’at till the domed strata—yeah, ’at’s the ticket—they can’t support the shear stress an’ they rupture, all back unner that ice on the other hemisphere too I bet, uh-huh, an’ you get lotsa cyclin’ in the surface materials, rip open the seams ever’ couple hunnert thousan’ years, think what that does to the rep rate with the atmosphere when you bake out that iron exposed fresh ever’ time—”
Channel #5: “Look, that’s one thing we do know: look at that spectrum, it would be a reducing atmosphere with all that iron, for sure, except the oxygen levels get pumped up, but even so it’s only around the two percent level, two percent 02, you can see that right here, look, it’s just a spike out on that wing, the line strengths are wrong, nothing like Earth, but I bet it’s the same damn process, the same way our air converted over from reducing billions of years back, trouble is it’s not much O2 is it? Not damn much if you want to breathe down there.”
Channel #6: “It’s both forms, open your eyes, lay that one over the other and it jumps right out at you—”
Channel #3: “Ah, ferrous and ferric. Both. So there’s a lot of oxygen down there, as much as Earth, but it’s tied up in the iron.”
Channel #29: “—nothing I could say would—”
Channel #20: “—so see this fits what the backscatter boys say, the faultin’ rips up the goddamn turf so much the iron gets reprocessed alla time an’ the air, it jess can’t hold onto its oxygen, the water jess runs off ever’ time it rains an’ the sea, it’s jess this solution a ferrous crap, ’at’s where th’ O2 is, man I tell you—”
Channel #56: “That jocko over in P4 has got some crazy idea, lissen to him, thinks it’s all iron, but give a gear at this, in the big spot there, see that big volcano, that’s sulfur for sure, big spouts of it coming out reg’lar as Maybelle, sulfur volcanoes smack in the middle of the Eye, and if that doesn’t tie up a lot of oxy, with those winds, I mean, we measured gusting velocity from the action-frame zats and they’ll mix the whole damn atmosphere in two, maybe three years, so you’ve got sulfur oxide all down there, that’s what the Eye is, that’s not sand dunes, not silicon dioxide, it’s sulfur dioxide—”
The picture sharpened as computers edited out random refractions from the clotted air below. Isis swam nearer.
