“Whatever the one that gets us is,” Charlie answered bitterly. “If that's dealt with, I still want to talk to you about Mars—”
Lag. “Listening.”
“I had another thought.”
“Most scientists are satisfied with three or four unprovable hypotheses in a career, Chuck.”
“Instead of three or four a week?”
Paul's laughter. Charlie got up to microwave his face cloth again. The steam did help. He pulled another cloth out of the plasti-foil pack while he was up, and heated that one to lay across his scalp and the back of his neck, where it could ease aching muscles. God, for a steaming-hot, old-fashioned dirt-side shower— “Do you want to hear this or not?”
“Sure,” Paul said, easy and relaxed. Before he'd become Riel's science adviser, Paul Perry had been a number of things. One of which was a consultant on the government side of the joint Canadian/Unitek Mars mission that had discovered the two vessels buried under the red planet's wind-and water-scarred surface. “Tell me your crackpot theory, Mr. Bigshot Xenobiologist.”
“There's an ejecta layer over the craft on Mars.”
“There's an ejecta layer over most of Mars. And isn't it several ejecta layers? I know your dating of the ships relies heavily on the geology.”
Charlie breathed in through steam, bending double to cough as the glop on the back of his throat peeled loose. “Good — God,” he gasped, tasting sour-sweet metal through even the camphor reek of the cloth. He sat down on the stool bolted in front of his secondary interface. “I think my dating was wrong.”
“Wrong how?”
“I said the ships had been there about two, three million years. Which would put it very close to the development of sentience on Earth.”
“Close, geologically speaking.”
“But now I think it's closer to sixteen million years.”
Dead silence through the link. Charlie smiled. “You see why I called you?”
“Why do sixteen million years and Mars sound familiar—” Paul's fingers were moving rapidly enough over his interface that Charlie could pick out the sound of the enter contact being depressed. “You're talking about ALH84001.”
“I'm talking about life on Mars. Above the microbial level.”
“That doesn't make any sense, Charlie. Why ground a ship on Mars — wait. Presumably you're assuming that the — that they were using their derelict ships in somewhat the same way the Americans used Viking or the old Soviet Union did Venera—”
“Space probes. Sure, why not? If they needed an FTL drive to get here anyway, and they were junking the ships—”
“Spoken like a Yankee, Chuck. Do you have a box in your garage labeled ‘pieces of string too small to save'?”
“If I had a garage, I probably would. As it is, I travel light.” The cloths had cooled; Charlie didn't have the energy to get up and microwave them again. Memo to me, he thought. Invent a cold cloth with an integral heating circuit. Why hasn't anybody thought of that?
Maybe the microwave manufacturers get kickbacks—
“But why Mars? We've got evidence of microbial life sixteen million years ago, but—”
“How long did the Venera probes last?”
Tapping. It was always reassuring when Paul didn't just know something, Charlie thought. “None of them over an hour.”
“Earth's a much more corrosive environment than Mars,” Charlie hazarded. “Maybe they did send us ships, and they didn't survive. Or maybe they were keeping an eye on Mars because the life there was so much more fragile. Earth's ecosystem has survived some pretty astounding blows—”
“You're thinking of the Yucatán meteor impact, aren't you?”
Charlie laughed, which turned into a gagging cough. “God damn this cold. That was a sissy hit, Paul. We got one about 251 million years back that made that look like — nothing. And the ALH84001 meteorite is the remnant of a relatively minor knock that still managed to kick chunks clean off Mars. Mars doesn't have the gravity or the atmosphere Earth does. The atmospheric blowout, water and oxygen and carbon loss from a few of those would have put paid to whatever chance multicellular life might have had there.”
“So what do you think the ships were for?”
Plaintively. Charlie managed not to laugh this time. “You're the sober, responsible ecologist. I'm just a wild-eyed xeno guy. I come up with the crazy theories, you figure out why they don't work. I'm reasonably certain, though, that after all my work with the nanotech we're using on the pilots, it was intended for organic interfacing. And the freaky thing: it self-adapts. You show it a cat and it knows it's a cat. You show it a beet and it knows it's a beet. I haven't gotten any beet-cats yet.”
“Why do you always get the fun jobs?” Paul sighed. “What if the ships were part of a, a — terraforming — no, a xenoforming attempt that failed?”
“Hey, you do okay with the crazy theories on your own.” Charlie grinned, the cold cloth dangling forgotten from his fingers. “Huh. Possible. Or possibly they're interstellar altruists who dropped their nanotech off on an ecologically damaged Mars — figure the atmosphere leakage had already started, say, or a little axis wobble, or what have you — to see if the ecology could be reconstructed. To see if those Martian microbes would evolve into something more impressive, given a fighting chance. And then the system got nailed with another couple of catastrophic failures — like the meteor impacts — and folded. It makes as much sense as them leaving a couple of ships there so the hairless monkeys would be able to call next door for a cup of sugar if we ever got off our own little blue rock.”
“Miocene, Charlie. Not that there were hairless monkeys—”
“Fussy. Carcharocles megalodon, then. Space sharks.” Charlie braced his palms together, fingers meshing and biting air, and laughed at his own childishness.
“Carcharocles translunaria. Ew. What an image.”
Charlie could picture Paul's elaborate shudder, and dropped his hands, scrubbing them against his trousers. “If they didn't take a crack at Earth, there could be two reasons, I guess.”
“One, they liked Mars better. It was more like home.”
Charlie nodded, forgetting Paul couldn't see him. “Or, as you said. Earth was more hospitable to life than Mars.”
“So?”
“So maybe they're good guys. Anticolonialists. Maybe they figured we had a chance on our own.”
A long silence, and then Paul Perry laughed ironically, his rich voice made tinny by distance and empty space. “Our own colonial history as hairless monkeys is so rife with altruism, after all. Don't go buying into that twentieth-century cultist trope that the aliens are advanced and enlightened, Chuck. It worries me. Figure the odds.”
Figure the odds, Charlie thought, wondering how naive he could possibly be. And then figure the odds on life. And then consider the difficulty you have talking to your pet dog, Paul, and figure the odds that life from another planet will want things that are even comprehensible to life from ours. He sneezed again and wiped his nose on the camphorated cloth.
0500 Hours
Monday 6 November, 2062