Authors: Gabrielle Walker
He was delighted by my look of confusion, and walked over to where a small rock was sitting on the gravel. âThink about it,' he said. âMy family is religious, I went to church, heard about the time of Jesus two thousand years ago. Think of everything that has happened to the world since then, and through all that time this rock has just been sitting here. If I'd walked here a million years ago it would have looked like this. Ten million years ago, before humans ever walked anywhere, this is how this valley looked. It's a window back in time.'
The tectonic forces that cause the rest of the world to buckle and warp have been subdued here for an extraordinary stretch of time. âYou're looking at the most stable landscape on Earth,' said Dave. âNothing even comes close. The Grand Canyon was carved in its entirety; the alps in New Zealand have risen to their great heights and all the while nothing happened here.'
I was awed by the sense that time was standing still there. And not just in the past but in the future, too. Though other parts of Antarctica might now be feeling the heat, Beacon Valley was insulated from almost everything. Only a big tectonic changeâa clashing of continents that altered ocean circulationsâwould be likely to have an effect here. And that isn't likely since the rest of the world's continents are now all moving away. âWe know what the future's going to hold in Beacon Valley,' said Dave, âand it's more of the same.'
And that's what makes Beacon Valley Mars-like. Today, the Red Planet is old, cold and dry. Nothing moves; nothing changes. Just like here.
As we walked, our bunny boots made striated oval footprints on the silt, like the ones Neil Armstrong left on the Moon. I told Dave about imagining myself on Mars, and then hopping from rock to rock on the way here so that I didn't leave any violating human trace. He laughed. âThis landscape isn't just old, it's also stable,' he said. âSo if you change something it wants to go back.' He pointed to my space-man footprint. âThe tread will be gone after one storm. The outline after a summer. And after a year, there will be no sign that it was ever there.'
Back at the site, I met the other half of the scientific match. Jim Head appeared graver, with a soft, courteous Virginia accent. He was maybe twenty years older than Dave, and his white hair and beard, and the staff-like pole he was carrying, made him look like Gandalf, the wizard from
The Lord of the Rings.
Though he was the elder and more experienced of the two scientists, he was the guest here, and marked this, slightly self-mockingly, by calling Dave âsir'.
Jim's first job, just out of graduate school, was to advise the Apollo programme where to land on the Moon. (He said he had answered an advertisement that read: âOur job is to think our way to the Moon and back. Call this number.') He had to choose somewhere that was interesting geologically to make the science of the mission worthwhile. But if the soil had been too soft in the Sea of Tranquillity, the Eagle could have sunk irrevocably into the lunar dust. If the ground had been sloping, the craft could have rolled. Buzz Aldrin and Neil Armstrong would have been tossed and tumbled inside their craft and their journey might have ended there. When the world watched on 20 July 1969, Jim's daughters asked: âWhere's Dad?' Dad, it turned out, was in a side room at the Apollo Control Center, watching and listening as the pictures rolled in. His choice of landing spot worked perfectly.
16
Since then he has been obsessed with planets. He talks about them with an easy familiarity, as though they are old friends. âOn the Moon you could move along pretty fast. On Apollo 17 Jack [Schmitt] really got the lunar gait down. He practised a lot of different ways but the best one was hopping. There are some very funny pictures.' What about Mars? âYou probably wouldn't hop on Mars,' he says. âThe Moon's surface is much more forgiving, like a soft soil. On Mars you could launch yourself more than you wanted to and come crashing down. Trudging is the way to go there, pretty much the way we do it here.'
I asked him what his favourite planet was. âThe Earth,' he said immediately. âBut after that, Mars.'
And that was why he was here, in this most Martian of places. Though he had trained astronauts for manned missions and robots for flights to Venus, Saturn and Mars, he had never walked on the planets he studied, or touched them, or tasted them. His job was to use his imagination. What should the astronauts collect? And later, what would the landers and rovers see? What should they pick up, or turn over, or test? How can you picture a landscape when all you had to go on was the rigid view of a robot camera?
He started telling me about the Vallis Marinaris canyon system up on the Martian region of Tharsis. The canyon itself is vast, a single feature stretching the equivalent of the distance from Boston to Los Angeles. And yet, the resemblance to here is still uncanny. Beacon Valley is almost a montage of parts of Vallis Marinaris: the wind, the quiet, the ancient surface, the steep cliffs, the polygons and rocks that look just like those seen through the camera of the Viking lander.
There is also the way the ice here tiptoes over the land without leaving a footprint. In most other icy parts of the world, glaciers are wet. They scrape along on a thin film of water, gouging out valleys and scratching the rocks as they pass. That's what you get in the Alps, and the other places that have informed glaciologists and geologists for generations. But here, glaciers behave differently. They are old and cold and slow, and their bases are stuck to the ground. Instead of sliding, they flow sluggishly like treacle. They leave few scrape marks on the surface, but the piles of rocks they leave behindâformed as rocks fall from the cliffs on to their surfacesâlook exactly like the ones on Mars.
17
When Dave first told Jim about Beacon Valley he was gobsmacked. âIt was an epiphany for me. It was like, shht, that's how it works on Mars, too!' (He actually said âshht'. That's how he pronounced it. Jim might mimic swear words but I can't imagine him actually using one.)
Now Jim was excited as he started reeling off the many ways that Beacon Valley reminded him of Mars. There was the lack of liquid water; the low erosion rates; the incredibly cold climate. Here in the upland zone of the Dry Valleys, he said, it was a hyper-dry cold polar desert. âAnd that's what Mars is pretty much everywhere.'
So though Jim was helping Dave investigate the scientific details of Beacon Valley's surface, he was also on a training exercise for his imagination. âWhen you're here you can walk around. You can look. You don't have to wait for the wind data to come in, you can feel the wind. You see the way the light falls. You can immerse yourself in the landscape.'
In his office in Brown University one of his students had painted a sign in calligraphy to hang on his wall. It bore one word: Daydream. âYou know,' he said, âin case I forget.'
That evening, I discovered that Dave and Jim ran the most whimsical camp I had yet encountered. They used animal sounds for the wake-up callâa different one for each day. Tomorrow, Saturday, would be âEee-awww' which turned out to sound like a donkey with a bad hangover. Sunday would be the cawing of a crow and Monday, ambitious, thisââa mockingbird imitation of a jay'. They named their thermos flasks according to a theme. This year, the theme was âobscure people'. Jim's was named after Joe Engle, who was the astronaut kicked off the Apollo programme at the last minute to make way for Harrison âJack' Schmitt, âthe only true geologist who's ever been to space'.
Toilet facilities were unusual, too. There were the normal pee bottles of the Dry Valleys, to be poured, when full, into a U-barrel. But for the rest, there was an arrangement little short of a throne. To use it you âdeclared' in front of everyone, so there was no danger of subsequent embarrassment through the lack of lock, or indeed of door. A short stroll then took you to a sit-down box on the edge of the camp, set in the natural shelter of a small wall of boulders. To the right were age-old chocolate-coloured cliffs. In the distance, the folds and sweeps of the Taylor Glacier. Barring the few souls in the camp behind you the nearest human was hundreds, perhaps thousands, of kilometres away. This was a smallest room with the biggest, most majestic view.
Though people slept in individual tents, the main activity centred around the cook tent, which contained two cots that doubled as couches, and two stoves on either side of the door. Hanging from the ceiling, among the defrosting dinner, plates, drying socks, gloves and hats, a cock-eyed Santa Claus and his spindly legged Rudolph, were two miniature speakers, precariously attached with duct tape beside an iPod cable. I'd brought fresh fruit and bread to try to win these guys over, but maybe fresh music would be a better idea. It was 8 p.m. now, and most of us were already in the tent, waiting for Dave to join us. Hesitantly I offered my iPod. âAre you looking for some new tunes?' I asked. Conversation stopped. Someone said: âYou don't . . . by any chance . . . have any Tom Jones do you?' Seven pairs of expectant eyes turned to me.
As it happened, the answer was yes. I'd made my collection as eclectic as I could and now it looked as though it would pay off. Everyone was bizarrely excited. âShh! Don't say anything. Quick! Before he comes!' Within a few minutes the first few bars of âIt's Not Unusual' came belting out of speakers cranked up to top volume. Outside there was a roar. Dave ripped open the door and lurched into the tent, his eyes shining. Everyone was laughing and shouting at once. Eventually I discovered that Dave long ago declared this to be the official camp song; but someone took the CD last season and they'd been missing it like crazy. Tom Jones has no idea, I thought to myself. This was about as unusual as it got.
That night, I wondered why so many men and women in Antarctica felt the need for whimsy like this. In some cases it might be like whistling in the dark: you had to show bravado in the face of a hostile environment. But Dave and Jim and the team didn't seem remotely afraid of this place. They clearly loved it. In the end I decided that it was partly because they worked so incredibly hard here, from early morning till late at night; the laughter was for release. But I also sensed that it came out of exuberance at doing their science in a place that clearly made them feel alive.
The next morning brought clear weather and a good working day. As we hiked over to a new site, Dave explained what he was investigating this season. It was all about ice. Beacon Valley was ringed around with smaller valleys like catchers' mitts, which trapped the snow blowing down from the plateau and turned it into ice until it formed glaciers.
Rocks tumbling down from the steep sides of the valley coated the glaciers with a thick dark surface, and this protected the ice at least for a while. But as the glaciers moved sluggishly towards Beacon Valley the prurient fingers of the wind succeeded in poking through gaps in the rocks, sand and silt and whipping away whiffs of ice vapour. By the time it reached the centre of Beacon Valley, far away from the sources, the ice should all have vanished.
But it hadn't. One day, when he was digging around in the rocks, Dave's shovel clanged against something that was unmistakably ice, where no ice had the right to be. Yesterday's experiment with the sledgehammer was intended to send seismic waves down through the ice to the rock beneath, to measure how thick it was. Today, he meant to drill into the ice and pull up some samples.
As we hiked, I started to think about the heroic explorers of old. Like most of the people that I'd met down here, the team had read about those early Antarctic exploits. But very few from the heroic age made it this far into the uplands. Beacon Valley was barely touched till the helicopters could make it inâand even now very few people had stood here. I wondered if that made these scientists feel like explorers themselves. Dave considered the question. âFor me it's the science,' he said finally. âIt's not about standing where no one else has stood. It's about finding things. Thinking where no one else has thought.' He stopped suddenly, his face alight. âOh, wow! Let me show you something
really
interesting! I didn't know we had already crossed over into the yellow brick road.'
He started scrabbling at the pale golden rock that had appeared beneath our feet, half hidden by chocolate-coloured boulders. âLook at him, he's like a leprechaun,' Jim said, adding with a heavy Irish brogue: âPot o' gold.'
âPrecioussss . . .' hissed Dave, piling slabs of the yellow rock into his arms. âMaster says I can have it.' He was leaping and bounding from side to side, making us all laugh, before he stood up and started placing the samples into a bag. And then he looked at me with a wide grin. âYou know how we were talking about discoveries. Well, you just walked on one.'
This pale yellow rock was once volcanic ash; though it didn't look like any ash that I'd seen before, that was because it had been around for a while. But the important thing was that if you had ash you could get a geological age. When a volcano erupts, the cloud of debris that it throws into the air contains minerals that act as tiny cages trapping radioactive elements inside. The cage is so small that nothing can get in or out. All the radioactive elements can do is gradually decay, tick, tick, tick, at a precise rate just like a clock. If you find these tiny cages and measure the ratio of what is left inside, you know how long ago the eruption happened.
That mattered because this particular layer of ash lay on top of Dave's buried ice, meaning the ice must have formed before. And when he measured those ticking clocks, they told him that his buried ice was at least eight million years old.
18
Ice! The most vulnerable solid on Earth. The material that melts as soon as you look at it. It's almost inconceivable that such stuff could survive intact on Earth for so fantastically long. At first nobody would believe it, and Dave has had to make his case again and again, with multiple ashes and detailed models, to win over his scientist peers. But now, most were convinced that the ice buried in Beacon Valley was by far the oldest on Earth. And by drilling into it, Dave hoped to get samples, actual bubbles, of the ancient air trapped inside.