Yan Liu raised her face to the sky, feeling the drops of rain splatter against her cheeks. Grey, low-hanging clouds canopied the desert, with thin wisps of vapor trailing below and behind them. The raindrops themselves felt heavier than normal; they struck almost hard enough to cause pain, accelerated as they were by the planet's high gravity.

This was the first sizable rainstorm observed in Gaea's temperate zone. It was technically nothing but a remnant of the massive, global hurricane that spanned the entire sun-side hemisphere, cooled from a scorching vapor to a pleasantly warm drizzle. It was a blessing; many had begun to worry that the farms would run out of water, and that the colony would be left to starve.

But of course, all boons came with their curses. The interaction of boiling and freezing air had already started creating powerful winds, and many of the atmospheric scientists predicted that supercells would begin forming in the region soon. The possibility of tornadoes was a whispered rumor.

On the horizon, smudged with mist, Liu could make out the angular faces of the hill, and the pebbles of human civilization clustered around it. Fields of greenery extended around the village, stretching almost to where she stood. Beside her was the white, plastic hull of a large rover. The front windows were broad and black, forming a bubble of glass around the driver's seat. On top of the rover was a veritable forest of antennae and sensors. Beads of rain water marred the EXN logo sprawling triumphantly on one flank.

The rain gradually became more persistent, falling like a shower of marbles from the overcast heavens. Liu decided to take shelter. She turned to the rover and climbed in.

The main cabin was roomy, with black rubber floors and soft yellow lighting. The walls were dominated by computer monitors, each spitting out streams of data. One of the monitors showed a weather map, with wisps of green and red across a black background. It seemed the worst was still to come.

This was the Iapetus rover, an exploratory vehicle designed to roll its way over an entire planet's worth of land. The rover was one of a fleet of twelve identical vehicles, each named for a different Greek Titan. The Iapetus was the god of death, the piercer. Maybe not the most cheerful namesakes, but Liu decided to ignore it in favor of the rover's utility.

A man appeared from the back of the rover and waved a greeting.

"Hey! I'm Amit Gabriel. I'll be your partner for the expedition. And you are...?"

Liu smiled and reciprocated the gesture. "Liu."

"Well, Liu, I hope you're ready for a couple months on the road. This planet's a big one, and we'll be making frequent stops."

"If you're asking whether I'm ready to dig up some secrets, most definitely. You're a geologist, right?"

"Yep. And Gaea is a very active girl. Volcanoes, earthquakes, it seems the rocks themselves are alive."

"Too bad nothing else is," said Liu with a disappointed frown.

"Sure it is. I mean, here we are. Even if Gaea was barren before, she's become quite fertile enough in the last few weeks. And who knows? Maybe we'll find something extraordinary out there."

"I hope so."

The two parted ways and prepared their respective quarters. The storm outside beat down with increasing ferocity. Rivulets of water turned into streams, then roaring floods of murk. Eridu was spared the worst of the flooding, protected as it was by the hill, though the farms suffered.

Slowly, the storm subsided. As the roar of rainfall died to a patter, the sound of rushing water took over. Liu stepped into the driver's bubble and watched the new river as it coursed away from the mountains. The storm stood ominously, a tower of grey vapor in the sky to the east.

The torrent of rainwater began to dry up within the hour, and the Iapetus was finally able to embark. The six wheels struggled to make headway in the wet, sludgy ground, but still the rover rolled forward. It seemed that the small bump of the hill took far too long to sink below the horizon. Liu gazed out of the driver's bubble, not once touching the controls, as the Iapetus made its slow, arduous way through the mud, studying the horizon closely. Gaea had nearly twice the diameter of Earth, making the horizon unsettlingly distant.

On closer inspection, Gaea was a very disorienting place. Having been locked in the confined of the Facem for six years, it had evaded her notice for some time, but looking at the raw planet in its raw form seemed to bring up memories of Earth, and all the alien differences came into stark focus.

For one, the sun was very dim. It was certainly hot enough, and even now seemed to beat down from its perch on the tops of the mountains. But the light it gave off was surprisingly weak. Liu could almost look at it without causing herself any pain. There was also the impossibly wide horizon, large enough to look vaguely bowl shaped. Ironically, it made her feel claustrophobic. And of course, the pull of gravity, like bricks tied to her legs and arms, sucking her down.

The first few hours of the expedition were silent for the most part. Liu and Amit did what they could to make small talk. She learnt that he lived in Jing-Jin-Ji before the Facem, shared some stories from back at Copenhagen, but the conversation inevitably tapered out, sputtering out in the constant whine of the rover and the oppressive crush of the planet's gravity. Eventually, the two scientists retreated to their own corners of the Iapetus.

After a restless night, full of light and worry, Liu woke to find the city of Eridu gone. Nothing but empty, flat desert surrounded her on all sides, with the mountain range looming in the distance.

Amit spoke from within the rover.

"We'll be stopping sometime soon. I hope you got all your equipment ready."

Liu grunted an affirmation and turned back to the panorama outside.

The Iapetus, being an exploratory and scientific expedition, would stop once every few hundred kilometers to allow the two scientists to run tests and take samples. The hope, at least for Liu, was that the initial tests for biological activity had not been careful enough. She would be the first to find life from outside Earth's biosphere.

But maybe not here.

As Liu left the rover, she was struck with a stinging barrage of sand and dust. The desert was a bowl with her at the bottom, and the wind blowing from every direction. Liu and Amit hurried to scoop up dirt and insert little probes into the cracked soil. Excitingly, the sand immediately below the surface was dark with moisture, from yesterday's storm. Maybe something could grow here.

Awkwardly shielding their faces with their arms, the two scientists struggled back into the rover, bringing with them a few bags of samples, data, and a flurry of loose dust. After a quick shower to wash of the grit, Liu sat at one of computer monitors and began picking apart the information.

The hours trickled by, uncounted by the sun or the landscape outside. Still the Iapetus rolled, and the wind howled, and Liu studied the screens, until finally she found her answer.

The soil was dead. It had greater water content than expected, with slightly more iron oxide, but no life. Liu went to sleep that night disappointed, to say the least, but with some hope for the following day.

The next day was much the same. An endless flat, hours of study, followed by disappointment. At the end of the day, with the sun still shining through the windows with all its power, Liu and Amit ate. Liu spoke.

"I've found nothing. There's nothing out there."

"You can't say that for sure. Not yet, anyway. We've covered maybe three hundred kilometers, that's hardly a good measure of..."

"Tell me truthfully. Do you think I'll find anything?"

"Liu, you know that I don't know. My only advice is to wait and see. Who knows? Maybe tomorrow will be your day."

Liu ate her afternoon meal that day in the driver's bubble. She found herself staying there more and more of the time lately. She stared out at the desert and breathed the filtered air of the rover. The food was a tasteless mash derived from fungus and hydroponically grown legumes, perfectly befitting the sensory wasteland beyond the glass. This is not what she came for. She wanted some activity, change, something as vibrant as Earth, not dead like Mars or Venus. Or anywhere.

The morning brought promise. Sitting on the horizon was a shield volcano, almost flat against the desert plain, spewing molten rock in a lazy stream. It glowed vivid red, the mountain itself black and grey.

Amit emerged from his bunk.

"Would you look at that! I told you there'd be something!"

"I have to admit, this is a welcome change of pace. Here I was thinking this planet was dead, and then this comes along."

"Can't imagine there a whole lot living there though. Sorry."

"Oh, no need to apologize. Besides, there are some species of bacteria living in extreme environments on Earth. Who knows."

Liu and Amit drove to the base of the shield volcano, where ropes of dark, hot rock accumulated in great piles of steaming stone. The heat, oppressive even under normal conditions, was downright palpable so close to Gaea's beating heart. Shaking and sweating, Liu scooped the dirt and newly formed stone into a vial and watched it crumble, settling into the bottom. Feeling the increased gravity pulling her to the ground, she got up from her crouch and trudged back to the rover. From the door, she watched Amit hurry from boulder to boulder, scraping off little puffs of dust at each one, before almost sprinting off to another. She smiled.

The volcano continued to roar far above, producing an umbrella of molten rock that forever hung over the caldera. The wind seemed to be quieter, awed by the raw power of the planet.

Once they were back inside the rover and moving away from the volcano, Amit and Liu discussed the expedition.

"I'm still running my tests," said Liu, "I'm hopeful for this batch."

"I'm hoping with you. But, seriously, that volcano was too much. I feel spoiled. Did you know that there are only three celestial bodies in the known universe with volcanic activity? This'll be the fourth, and I'm the first to see it happening!"

"Do you think this is how the first explorers on Mars and Luna felt? The first in every sight they saw, every patch of ground they walked on?"

"Must have been. But ours is the better experience, isn't it? No space suit, nothing to obstruct us from exploring this new world to our greatest content!"

"I suppose not," said Liu, sighing. The rover was almost silent for a time, filled only with the sound of wheels rolling over gravel.

"Amit," said Liu. "I was thinking."

He looked bemused. "What?"

"I'm not sure if I like this place. I came here to find a new world. But all I see is desert."

Amit smiled. "Oh, you just wait. Here, let me show you something." He turned to the monitors and brought up a map of Gaea, compiled from satellite data. Liu realized she had never actually seen a map of the whole planet, and scolded herself for never making the inquiry.

The map was split between blue ice and yellow dessert, with two thin bands of brown and red arcing across opposite sides. A red indicator flashed the location of the Iapetus.

"You see where we are? Right there? Well..."

Amit zoomed into the map, highlighting the area near the rover. For miles all around, there was nothing except orange-brown desert, but about fifty kilometers to the north was a large lake. On Earth, it would have been no bigger than Caspian Sea, but it was far bigger than any body of water Liu had seen so far.

"Eh? What do you think?"

"I think it's great! Do you know what this means? Open water is the one thing everyplace has missed!"

"Huh?"

"Mars, Europa, Enceladus. They're all planets or moons that biologists thought would have life on them, because they all had liquid water. But none of them do. But this lake almost exactly replicates the environment on Earth. This could be it, Amit!"

"Well, that's fantastic! Can't wait for tomorrow."

Liu grinned and went to her own quarters while Amit smiled after her.

Later that night, with the sun still shining brightly on the horizon, Amit was still studying the samples he had gathered that day, scrutinizing motes of dust and flecks of stone, when a message arrived on the comm system. A stern looking man with a well-groomed beard appeared on one of the monitors.

"Good afternoon, crew of the Iapetus. This is Lieutenant Hernandez speaking. The scientific staff here at Eridu has decided they would rather the expedition divert from its current path and take a more easterly one. Starting tomorrow at oh-six hundred, your rover will change bearing to north-northeast, and continue on that new route. The purpose of this change of course is to survey the ice fields and investigate the prehistoric state of Gaea's atmosphere. We wish you the best in the coming endeavors."

The face blinked out and Amit found himself staring at his own reflection.

The glaciers that covered Gaea's dark hemisphere could be very old, and thus contain trapped air bubbles formed thousands, perhaps even millions of years ago. He was hardly an atmospheric scientist, but the idea was attractive nonetheless. He realized only a few hours after, as he was drifting off, that the new course would take the rover away from the lake.

Liu was not in a good mood the following morning. She silently watched the desert roll by, and Amit kept his distance.

There were no samples collected that day, and the two scientists busied themselves as best they could. The rock samples from the volcano contained many basic organic molecules, which was encouraging, but there were no active microbes. Amit's own studies had been much more promising, showing that the planet's upper mantle, and thus the igneous rocks forming at the volcano, was very similar to Earth's, though slightly heavier in ferromagnetic metals.

At last, the day began to draw to a close. The scientists ate at opposite ends of the rover, with Liu, as was her norm. At first, the scene outside seemed outside seemed just as bland and monotonous as it always was, but the more she looked at the horizon, the more she was put off by something. She finally realized that the problem lay in the sun; it had dipped, miraculously, so that now it hung partially obscured by the distant mountaintops. This detail opened a whole universe of little intriguing differences in the landscape. The shadows were longer, the dirt redder, the sky dimmer and painted purple and orange, the sunlight scattered by Gaea's thick, swaddling atmosphere.

Liu soon noticed a thunderstorm brewing on the horizon, tall towers of grey cloud piling up on the brim of the global bowl. She decided she would hold out. Maybe the glacier wouldn't be so bad.

"You know that storm's gonna halt our progress for at least a few hours."

Liu turned to Amit as he leaned into the bubble. He immediately flashed an apologetic face and bowed his head. "Hey, sorry for building up your hopes yesterday. I didn't know..."

"I don't blame you."

Amit smiled tentatively before continuing. "Yeah, well the storm is a big problem. Forecasts say it'll put to shame anything we've seen yet. You ready?"

"I think I'll live."

The wind, Liu realized, was much quieter now than it usually was.

"Have you ever been to Luna?" asked Amit.

"No. I never left the Danube Administrative District."

"That's too bad. I ask because it really reminds me of this place. Endless, dark grey flatness. The horizon was closer, but it wasn't all that different. One thing I noticed was that the sky was this perfect blackness. No stars. If you lie on your back and look up, you can convince yourself that it's actually a huge pit, and you're falling into it."

Liu considered. "The world here is concave. I feel like an ant crawling in the bottom of a cup. I think that's worse."

"I suppose."

The two sat together for a moment, squinting out at the setting sun as it threatened to roll under the mountains and plunge everything into eternal night.

"It's like a cage. The gravity is like a chain," said Liu.

Amit looked at her and shook his head. "I think you'll get used to it." He smiled a hopeful smile and receded back into the rover.

The storm was indeed a terrible one. The Iapetus was forced to stop and wait for the clouds to clear as rainwater lashed its side and wind pushed it into a westward lean. The dusty ground turned to mud and the sky flashed white with lightning. Liu spent the day in her cabin, content to watch from the small, non-threatening porthole.

When finally the storm ended and the red sun peeked through the dissipating vapor, the soil was saturated, leaving a few centimeters of brown water bubbling across the surface. The endless sunrise shimmered beautifully over the ripples of the water, a perfectly reflected hourglass of red light straddling the horizon.

The rover trudged slowly through the quagmire, picking up speed as it went. It was soon moving at its usual pace, its wheels a blur as it skipped across the veritable wetlands. As the day progressed and the water was exposed to the withering stare of the sun, the shallow lake evaporated into tall wisps of steam. The sun continued to approach the horizon with each passing mile, slowly descending toward the mist. Toward the end of the day, Liu and Amit left the Iapetus to collect soil samples. For once, the air wasn't uncomfortably hot, but rather cool on the skin. Refreshing. The scientists went about their work with greater cheerfulness than they usually did. The oppressive gravity didn't bother her.

The next few days were quiet. The wind had died down to intermittent whispers, and there were no storms. The sun continued to drop, until finally it disappeared behind the horizon.

"So you've never been beyond the borders of Copenhagen?" asked Amit, one silent afternoon.

"No. Though I suppose now I have. You know..."

"Yeah. I take it you just never found the time?"

"More or less. I spent most of my time in the lab. Never really had a reason to leave."

"No field work? Not even a vacation?"