The Martian Race Read Online Free PDF Page B

notice a bone sticking out of the ground. Julia was more systematic and probed deeper in the obvious places, where water had once silted up and could have trapped recently dead organisms. Algal mats, perhaps, as with the first big life-forms on Earth. But she had no luck, even in a year and a half of snooping into myriad canyons and promising beds of truly ancient lakes. That didn't mean life wasn't somewhere on the planet. It had been warm and moist here for a billion years, enough for life to evolve, even if Mars had not supported surface life for perhaps three billion or more years.
    She stamped her feet to help the circulation. Space heaters in the rover ran off the methane-oxy burn, but as always, the floor was cold. Mars never let you forget where you were.
    She tried to envision how it must have been here, billions of years ago. This was her cliché daydream, trying to impose on the arid red wastes the romance of what they could have been, once upon a time.
    Did life give way with a grudging struggle, trying every possible avenue before retreating underground or disappearing?
    The planet did not die for want of heat or air, but of mass. With greater gravity it could have held on to the gases its volcanoes vented, prevented its water vapor from escaping into vacuum. Recycling of carbon didn't happen on Mars, the CO 2 was lost to carbonate rocks. The atmosphere thinned, the planet cooled …
    Split from hydrogen by the sun's stinging ultraviolet, the energetic oxygen promptly mated with the waiting iron in the rocks. The shallow gravitational well failed. Light hydrogen blew away into the yawning vastness of empty space. The early carbon dioxide fused into the rocks, bound forever as carbonate. Had Mars been nearer the sun, the sunlight and warmth would simply have driven water away faster.
    So those early life-forms must have fought a slow, agonizing retreat. There were eras when lakes and even shallow, muddy seas had hosted simple life—Marc's cores had uncovered plenty of ancient silted plains, now compressed into sedimentary rock. But no fossil forests, nothing with a backbone, nothing with shells or hard body parts. If higher forms had basked in the ancient warmth here, they had left no trace.
    The squat hab came into view in the salmon sunset.
    They had landed in the ancient flat bottom of Gusev Crater, whose distant ramparts reared over a kilometer into the rosy sky. A hundred fifty klicks across, Gusev was a geologist's playground.
    One of astronomy's more arcane pleasures was eclectic naming. Gusev was a mini–United Nations. To the south lay the Ma'adim Vallis, “Martian Valley” in Arabic. Gusev himself had been a nineteenth-century Russian astronomer. Some French Planetary scientists working for the Americans had given the small crater near their base the Greek name Thyra.
    She could see the slumped peaks of Thyra as she headed south. One of the major reasons to land here had been a tantalizing dark spot on Thyra's southern rim. Under telepresence guidance from Earth, Rover Boy had found promising signs that the spot was a salt flat left by a thermal vent. True enough, but when they arrived they found that the site had not given off anything for maybe half a billion years. A crushing disappointment, that first month. But if there had been venting, maybe there was still, nearby. She had lived with that ebbing hope for a year and a half.
    Well, now she had her vent. And it had injured Viktor within a few minutes.
    Looking like a giant's drum, seven meters high and eight meters across, the hab—their former command module—stood off the ground on sturdy metal struts. Sandbags on the roof cut their radiation exposure. Inside, the two stacked decks had the floor space of a smallish condo, their home for the last twenty months. A thousand carefully arranged square feet. Not for the claustrophobic, but they would certainly be nostalgic for it in the cramped quarters of the Return Vehicle they would shortly be