Only the crests of the tallest dunes were still in sunlight; the world was a black surface, marred by short scimitar curves of steely gray. Horizon about five kilometers off. Ann was crouching, a scoop of sand in her palm.
“What’s it made of?” Nadia asked.
“Dark solid mineral particles.”
Nadia snorted. “I could have told you that.”
“Not before we got here you couldn’t. It might have been fines aggregated with salts. But it’s bits of rock instead.”
“Why so dark?”
“Volcanic. On Earth sand is mostly quartz, you see, because there’s a lot of granite there. But Mars doesn’t have much granite. These grains are probably volcanic silicates. Obsidian, flint, some garnet. Beautiful, isn’t it?”
She held out a handful of sand for Nadia’s inspection. Perfectly serious, of course. Nadia peered through her faceplate at the black grit. “Beautiful,” she said.
They stood and watched the sun set. Their shadows went right out to the eastern horizon. The sky was a dark red, murky and opaque, only slighty lighter in the west over the sun. The clouds Ann had mentioned were bright yellow streaks, very high in the sky. Something in the sand caught at the light, and the dunes were distinctly purplish. The sun was a little gold button, and above it shone two evening stars: Venus, and the Earth.
“They’ve been getting closer every night lately,” Ann said softly. “The conjunction should be really brilliant.”
The sun touched the horizon, and the dune crests faded to shadow. The little button sun sank under the black line to the west. Now the sky was a maroon dome, the high clouds the pink of moss campion. Stars were popping out everywhere, and the maroon sky shifted to a vivid dark violet, an electric color that was picked up by the dune crests, so that it seemed crescents of liquid twilight lay across the black plain. Suddenly Nadia felt a breeze swirl through her nervous system, running up her spine and out into her skin; her cheeks tingled, and she could feel her spinal cord thrum. Beauty could make you shiver! It was a shock to feel such a physical response to beauty, a thrill like some kind of sex. And this beauty was so strange, so alien. Nadia had never seen it properly before, or never really felt it, she realized that now; she had been enjoying her life as if it were a Siberia made right, living in a huge analogy, understanding everything in terms of her past. But now she stood under a tall violet sky on the surface of a petrified black ocean, all new, all strange: it was absolutely impossible to compare it to anything she had seen before; and all of a sudden the past sheered away in her mind and she turned in circles like a little girl trying to make herself dizzy, without a thought in her head. Weight seeped inward from her skin, and she didn’t feel hollow anymore; on the contrary she felt extremely solid, compact, balanced. A little thinking boulder, set spinning like a top.
They glissaded down the steep face of the dune on their boot heels. At the bottom Nadia gave Ann an impulsive hug: “Oh Ann, I don’t know how to thank you for that.” Even through the tinted faceplates she could see Ann grin. A rare sight.
After that things looked different to Nadia. Oh she knew it was in herself, that it was a matter of paying attention in a new way, of looking. But the landscape conspired in this sensation, feeding her new attentiveness; because the very next day they left the black dunes, and drove on to what her companions called layered or laminate terrain. This was the region of flat sand that in winter would lie under the CO2 skirt of the polar cap. Now in midsummer it lay revealed, a landscape made entirely of curvilinear patterns. They drove up broad flat washes of yellow sand that were bounded by long sinuous flat-topped plateaus; the sides of the plateaus were stepped and benched, laminated both finely and grossly, looking like wood that had been cut and polished to show a handsome grain. None of them had ever seen any land remotely like it, and they spent the mornings taking samples and borings, and hiking around in a loping Martian ballet, talking a blue streak, Nadia as excited as any of them. Ann explained to her that each winter’s frost caught a lamina on the surface. Then wind erosion had cut arroyos, and stripped away at their sides, and each stratum was stripped back farther than the one below it, so that the arroyo walls consisted of hundreds of narrow terraces. “It’s like the land is a contour map of itself,” Simon said.
They drove during the days and went out every evening in purply dusks that lasted until just before midnight. They drilled borings, and came up with cores that were gritty and icy, laminated for as far down as they could drill. One evening Nadia was climbing with Ann up a series of parallel terraces, half-listening to her explain about the precession of aphelion and perihelion, when she looked back across the arroyo and saw that it was glowing like lemons and apricots in the evening light, and that above the arroyo were pale green lenticular clouds, mimicking perfectly the terrain’s French curves. “Look!” she exclaimed.
Ann looked back and saw it, and was still. They watched the low banded clouds float overhead.
Finally a dinner call from the rovers brought them back. And walking down over the contoured terraces of sand, Nadia knew that she had changed – that, or else the planet was getting much more strange and beautiful as they traveled north. Or both.
They rolled over flat terraces of yellow sand, sand so fine and hard and clear of rocks that they could go at full speed, slowing down only to shift up or down from one bench to another. Occasionally the rounded slope between terraces gave them some trouble, and once or twice they even had to backtrack to find a way. But usually a route north could be found without difficulty.
On their fourth day in the laminate terrain, the plateau walls flanking their flat wash curved together, and they drove up the cleavage onto a higher plane; and there before them on the new horizon was a white hill, a great rounded thing, like a white Ayer’s Rock. A white hill – it was ice! A hill of ice, a hundred meters high and a kilometer wide – and when they drove around it, they saw that it continued over the horizon to the north. It was the tip of a glacier, perhaps a tongue of the polar cap itself. In the other cars they were shouting, and in the noise and confusion Nadia could only hear Phyllis, crying “Water! Water!”
Water indeed. Though they had known it was going to be there, it was still startling in the extreme to run into a whole great white hill of it, in fact the tallest hill they had seen in the entire five thousand kilometers of their voyage. It took them all that first day to get used to it: they stopped the rovers, pointed, chattered, got out to have a look, took surface samples and borings, touched it, climbed up it a ways. Like the sand around it, the ice hill was horizontally laminated, with lines of dust about a centimeter apart. Between the lines the ice was pocked and granular; in this atmospheric pressure it sublimed at almost all temperatures, leaving pitted, rotten side walls to a depth of a few centimeters; under that it was solid, and hard.
“This is a lot of water,” they all said at one point or another. Water, on the surface of Mars …
The next day the glacier hill formed their right horizon, a wall that ran on beside them for the whole day’s drive. Then it really began to seem like a lot of water, especially as over the course of the day the wall got taller, rising to a height of about three hundred meters. A kind of white mountain ridge, in fact, walling off their flat-bottomed valley on its east side. And then, over the horizon to the northwest, there appeared another white hill, the top of another ridge poking over the horizon, the base remaining beneath it. Another glacier hill, walling them in to the west, some thirty kilometers away.
So they were in Chasma Borealis, a wind-carved valley that cut north into the ice cap for some five hundred kilometers, more than half the distance to the Pole. The chasm’s floor was flat sand, hard as concrete, and often crunchy with a layer of CO2 frost. The chasm’s ice walls were tall, but not vertical; they lay back at an angle less than 45°, and like the hillsides in the laminate terrain, they were terraced, the terraces ragged with wind erosion and sublimation, the two forces that over tens of thousands of years had cut the whole length of the chasm.
Rather than driving up to