Voyage (71 page)

When they’d finished, the SEP looked like an odd, multi-pointed star, with the radioisotope power package at the center, and the instruments set up on the ground all around it, connected by fine orange cables. The seismometer was that silvery paint tin. A little meteorology boom stuck up in the air – the SEPs would act as weather stations for the astronauts during their stay on Mars – and that spidery gold-leaf sculpture was a magnetometer. At the front of the assembly was a pair of tall, thin stereoscopic color cameras. And on top of the whole thing sat a delicate S-band antenna, pointing to an imaginary Earth.

The SEPs would be placed at a variety of sites, as the astronauts completed their traverses. There was every hope that the SEPs could send back data long after Stone and his crew had returned to Earth. It would be kind of a neat memorial to the mission; and now, looking down at the installed balsa-and-card mockup of the SEP, Stone felt a certain pride in his accomplishment, in a task done well.

‘Okay, Natalie, the SEP’s installed,’ he said. ‘What next?’

‘Rog. According to our checklist, here, one of you should be setting up the CELSS, and the other taking samples.’

‘It ain’t time for lunch yet?’ Bleeker asked plaintively.

Stone laughed. ‘I’ll do you a favor, Adam. You set up the CELSS, and I’ll hike around for the goddamn samples.’

They trudged back to the MET, and Stone sucked a little more of the flat, tasteless Tang from the tube at his neck.

I’d sure rather be watching the Olympics with a couple of cold ones at my side,
he thought. But there just wasn’t the time. He’d had no time of his own, it felt like, since he’d joined the Agency.

Stone helped Bleeker haul the mockup CELSS kit out of the MET. The CELSS, the Controlled Environment Life Support System, was a small inflatable greenhouse. It came packaged as a disk of plastic. Stone and Bleeker laid the disk out on the ground and Bleeker went to work on a small foot-pump, pushing air into the ribbing of the greenhouse; soon a dome maybe four feet high had taken shape.

By the time he’d done Bleeker was sweating even harder. ‘My God, Phil, it’s real work operating that damned pump in these boots.’

‘You want to go rock hounding instead?’

‘No, no,’ Bleeker said. ‘Leave me to my darn vegetable patch.’

He pulled a simple aluminum spade out of the MET and began to scrape without enthusiasm at the soil. Later he’d set up a little water sprinkler inside the dome, and he’d be planting crops – soybeans and potatoes. The idea was that the carbon-dioxide-rich Martian air would be able to reach the plants through the permeable walls of the greenhouse, and the plastic dome would trap a lot of the heat of the sun. Martian soil, it seemed from the limited Soviet lander results, contained most everything needed to grow crops save for phosphorus and free water, so Bleeker would be doping the soil with a nutrient additive.

This CELSS kit was just an experiment; there was no intention of growing foodstuffs to supply the first expedition. The point was to prove that crops could be grown on Mars; it would point the way to techniques for future, longer-term missions – and even the first permanent colony, off in an unknowable future.

Likewise, Ares would be carrying another long-term experiment called ISPP, for In Situ Propellant Production. The crew would set up kits designed to extract oxygen from compressed Martian air, and maybe hydrogen and oxygen from any accessible under-surface water. If it could be shown that propellants and oxidizers for the return journey could be manufactured on Mars, the weight and costs of future trips there could be cut by more than half.

Dragging the MET, Stone began to walk, more or less north of Bleeker.

‘Okay, Natalie. I’m coming off this layer of loess, now. I’m arriving on what looks like a gravel bed, loosely compacted. I can see striations. Kind of streamlined, like scour marks. It looks as if water has flowed here …’

York called, ‘Why don’t you make a sample stop?’

‘Rog.’

He picked a spot, reasonably level, and set up the calibrating gnomon. He walked around the gnomon, carefully photographing it from every side. Next he worked the mechanical tests. He pressed a spring-loaded metal plate against the soil, and thrust a cylindrical probe into the ground. Then he put a lump of aggregate into a crusher, a handheld nutcracker affair. He called out readings to Natalie York as he worked.

When he’d fully documented his site he took samples from the surface. He picked up loose material with tongs, rakes and scoops, and tried breaking a piece off a larger rock with a hammer.

Actually, the landscape baffled Stone. He’d been taking a geology field trip each month for the last year, and he’d gotten familiar with the subject to some extent. But he’d never seen an area like this.

Most EVA training was taking place out in the high deserts in the western USA. At one site, in Nevada, half a square mile of desert had been faked up to simulate the Martian surface as observed by the Soviets, with fine sand raked in, large boulders set deliberately on the surface. There was even a fake MEM descent stage set up there, a mockup of wood and paint. The MEM had a compartment for a full-scale Mars Rover, which you could pull down and unfold, just like the real thing. Now,
that
was a sim exercise Stone could appreciate: bouncing across a fake, but recognizably
Martian
desert, in a four-wheel-drive Rover …

But he really did not know what the hell was going on here today. How was this piece of shit in Washington State, across which they were dragging this fucking Apollo-class golf buggy, supposed to relate to whatever the hell was waiting for them on Mars?

After maybe half an hour, he’d piled the MET with carefully selected – and uniformly worthless – samples of Washington State. ‘Okay, Natalie, I figure I’m done here.’

‘Well done, Phil. We’ll make a rock hound out of you yet. But I still haven’t heard much about the morphology of your site.’

He growled, and wiped sweat from his brow with a dusty hand. ‘Give me a break.’

‘Come on now, Phil. Taking samples isn’t enough – you ought to know that by now – what’s crucial for the geologists is the context. Tell me what you see.’

Stone began to walk forward again. His pack chafed at his shoulders, but now, looking around more systematically, he began to
see some pattern, some logic underlying the landscape formations; and as he did so, he began to forget his discomfort.

‘I see a mix of landscape here. I see what looks like bare bedrock, and sedimentary stuff that’s been scoured out, and depositional material. As if left behind by running water.’

‘Good.’

‘The land here can’t be of much value. Light pasture, maybe; there isn’t much growing, certainly not in the bare rock faces. I think the rock is basalt. Volcanic, anyhow. The macroforms in the bedrock are mostly channels. The channels are pretty straight: not much sinuosity. They look as if they are basically river valleys, but widened and deepened. Maybe by glaciation?’ Great tongues of ice, flattening and deepening valleys, scouring down to the bedrock –’

‘Don’t speculate, Phil. The goddamn Apollo astronauts speculated all the time, and they confused the hell out of everybody. Just observe.’

‘Sure.’ Speculating test pilots, on Mars. Natalie’s number one nightmare. ‘I see evidence of channel anastomosis. And uplands left isolated between the channels.’

Back at the CELSS, Bleeker looked up skeptically. He called, ‘Anasto-who?’

Stone imagined York’s chagrin at that remark. Bleeker’s comparative backwardness at the geology wasn’t surprising. The guy was under real pressure; as well as field trips like this in support of the eventual landing mission, Bleeker was also working toward the D-prime Earth-orbit mission, next month.

But then, Stone reflected, Bleeker
was
supposed to be the landing mission surface specialist.

‘Anastomosis, asshole. It’s all in your Boy’s Coloring Book of Geology. Where a channel has been breached, and cut a branch through into another channel. Look. See the way the channels over there seem to diverge, then join up again. And you can see over there, where that bit of plateau has been left isolated. Cut off by the new channels.’

The isolated upland was like a table top of rock, stuck in the middle of the plain.

‘Yeah. Okay, I see it. So what caused the breach?’ ‘Phil –’

‘Okay, okay, Natalie. Don’t ask me questions like that, Adam. I won’t speculate.’
It could be glaciation, though. Must be. What the hell else could have caused so much damage to the landscape? A lava flow, maybe?

‘What other macroforms?’ York asked.

Stone climbed on top of a rock, the heavy pack banging against his back, and peered around. ‘More uplands, carved out of the sedimentary stuff. They look –’

‘What?’

‘Smooth. Streamlined.’ Like islands, their flanks smoothed out, left stranded by the drying out of a parent river. ‘And I can see what look like bars of gravel, some maybe twenty, thirty feet high. Kind of like sand banks. They seem to have formed behind outcroppings, maybe of loess, or bedrock. Like tails. The rock has grooves scoured in it. Longitudinal. The grooves flow past the islands, and the gravel bars.’

He came to a bed of loose clay and sand. ‘This is more loess, I think. I see –’

‘What?’

‘Ripples. Kind of frozen here, in the loess. Like small dunes, I guess. The dunes are stratified. It looks as if a river has dried out here.’ He stalked on over the rock. ‘I got pits in the rock surface. Circular, a few inches deep, width from a foot wide upwards. Scallop pits, I think.’ Gouged out by pebbles, carried by turbulence … ‘The whole place is kind of like a river bottom,’ he said. ‘Yeah. You basically have the topography of a dried-out river bottom – but magnified. Channels and bars and islands. All shaped by flowing water on a massive scale …’

He looked around with a new excitement, seeing the geology with new eyes, with Natalie York’s eyes: the deep-carved, breached channels, the huge deposits of loess, the carved-out islands. ‘Christ. Is that it, Natalie? Is that what you’ve brought us out here to see? Was all of this region formed by a
flood?’

‘You’re speculating again, Stone.’

‘Oh, come on, York.’

‘Okay. You’re right, Phil. At least, that’s the favored hypothesis.’

Bleeker gave up on the half-assembled CELSS, and came to stand close to Stone. ‘What is?’

York said, ‘In the Late Pleistocene – maybe twenty thousand years ago – much of Idaho and West Montana was covered by an immense lake. Called Missoula. Thousands of square miles of it. The lake was contained by an ice dam. The dam eventually burst, and released a catastrophic flood that swept over this area. Tens of millions of cubic yards per second, maybe a thousand times as much as the Amazon’s discharge rate –’

‘Jesus,’ Stone said.

‘Yeah. The existing streamways couldn’t cope with the sudden volume, so they burst; the valleys were widened and deepened, and interconnecting channels were cut – all the way into the bedrock – in hundreds of places. Thousands of square miles were swept clean of the superficial structures, right down to the basalt bedrock, and another thousand square miles were buried in river-bottom debris.

‘We’re left with hundreds of cataract ledges, basins and canyons eroded into the bedrock, isolated buttes and uplands, gravel bars thirty or forty yards high.

‘This is the scabland, Phil. There are only a handful of areas on Earth which show the effects of large-scale, catastrophic flooding so well.’

Bleeker pushed back his Snoopy hat and scratched his blond head, ‘It’s fascinating, Natalie. But I don’t see what it has to do with us.’

‘Okay. Phil, I’ve given you another pack of photographs. In the left side-pocket of Adam’s pack.’

Stone dug into Bleeker’s pocket and pulled out a plastic packet of black and white photographs. He leafed through them quickly, showing them to Bleeker.

Cratered plains: the images were of Mars, clearly enough. But here was a channel cut deeply into what looked like the tough, ancient landscape of the southern hemisphere. Here was a crater complex, overlaid by anastomosed channels. Here was a crater with a teardrop-shaped, streamlined island, like a gravel bar, collected in its wake; and ‘downstream’ of the crater, there were scour marks, running parallel to the island …

Stone was having trouble making sense of this. ‘Are you saying that Mars has suffered catastrophic flooding – like the scabland here, in Washington State?’

York hesitated. ‘
I
believe so. A lot of us have argued that, since the Mariner pictures came in. I’ve been studying the area you’re looking at, in those photos, since 1973. I guess I’m. the leading expert on it, now. And it seems to me the analogy between the terrestrial scabland features and the Martian morphology is too striking to be a coincidence.’

‘But not everybody agrees,’ Stone hazarded.

‘No,’ she conceded. ‘Some say the Martian “scabland” features are too big to have been formed by water. Schumm, for instance.’

‘Who?’ Bleeker asked.

‘Schumm says the Martian channels must have been
formed
by tensional factors in the planet’s surface. Cracks, modified later, maybe, by vulcanism and the action of the wind.’

‘Sounds like an asshole to me,’ Stone said, peering at the pictures. ‘I’m with you, Natalie.’

‘But if these Martian channels were formed by flooding,’ Bleeker said, ‘where the hell did the water come from? And where did it go?’

‘I’ll bet she has a theory about that, too,’ Stone muttered.

‘I didn’t copy, EV1.’

‘Go ahead, Natalie.’

‘Underground aquifers. Contained by tough bedrock below – maybe ten miles deep – and a cap of thick ice in the regolith above. Whatever lifted up Tharsis – a convection process in the mantle, maybe – must have caused the faulting that led to the flooding. The pressure of the water got to exceed the pressure of the rocks. All you’d need would be a breach on the subsurface ice cap for the water to gush to the surface, under high pressure.’

‘My God,’ Stone said. ‘Oceans, buried in the Martian rocks. How can we find out if you’re right, Natalie?’