Saturn Reaching

Clara Ransom rejected her parent’s fear of the future, of the universe and left their prepper homestead to embrace a life in space.

Her quest to understand life in the universe brought her to Saturn’s moon Titan. Beneath the massive ringed giant and Titan’s hazy skies she discovers one piece to the puzzle.

 

1

While pretty much the rest of the Diaspora colonists had to settle for enclosed habitats, pressure suits, and airless barren worlds, she got to take a stroll outside. Light on her feet, thanks to the low gravity, her insulated boots barely pressed into the powdery surface. Water ice “rock” pebbles dotted the landscape ahead, as it rose into two hills that ran together, smoothed by methane rains and wind.

Right over those hills was a small stream, a tributary to a larger valley, running through the site. The insulated suit wasn’t as stiff or heavy as a full space suit, and it did have a full helmet to protect her head and provide breathable air, sterile, cold air that froze her nostrils and had a metallic taste to it, but air. A mixture with outside nitrogen and bottled oxygen. Her suit trapped the carbon dioxide to return it to the base. So maybe it wasn’t entirely the same as taking a stroll outside.

Still, for a girl from the Northwest used to getting outside, it was better than nothing. Who would have imagined it? Clara Ransom, at thirty-four, was walking freely on the surface of another world. Not her parents, always feeling guilty about bringing her and her brothers into the world while they waited for it to end. For all she knew they were still holed up in their prepper compound expecting Diaspora to drop rocks on their head, attack the Earth with new scalar weaponry from space, or unleash a horde of Dr. Shelton’s mutants. And feeling betrayed by their own daughter.

She looked up from watching the ground and took in the view through the thick haze of the atmosphere. A huge round shape filled the sky above, visible despite the thick clouds. Saturn, with the thin blade of the rings reaching out into space. Impossibly huge, awe-inspiring, like an ancient god about to swallow up the sun.

Which was about to happen, in truth. Titan’s orbit was going to move into Saturn’s shadow. That was the whole reason for coming out here.

Her glasses rang for her attention. The heads-up hologram flashed a query. Incoming call.

“Ignore it,” Clara said.

The query vanished. She licked her chapped lips and wished, not for the last time, that she’d packed some lip balm or something before leaving Earth.

Through the orange haze, the bright blob of the sun hung at the edge of Saturn’s limb. The light, dim compared to being on Earth, was still over three hundred times brighter than the full moon on Earth. The haze cut into it and soon night was going to fall and last over a week.

Just like in one of those movies when the alien monsters came out at night to attack the explorers.

 

Her glasses rang again. Once more the query popped up, blinking insistently.

“Ignore it,” she said.

Clara walked forward, with the easy, bouncing gait of someone adapted to the lower gravity. She called it the penguin waddle, and the environmental suit helped cement the image. She flapped her arms and picked up speed. Put some proper wings on these things and they really could take off and fly in the thick air. She’d been pressuring Mac to authorize the work but their boss didn’t really like the idea of his team flying around the site.

It only took moments to reach the top of the “hill,” really more of a swell in the ground. She windmilled her arms to stop. Her breath sounded loud in her helmet.

Her glasses rang again.

“Ignore it.”

The site lay spread out beneath her feet. Straight lines cut through the rock-ice ground around the stream in complex geometric shapes. Pits and flat areas marked out other spaces. Sharp, unnatural lines, spreading out in a fan shape around the methane stream. A small circular pool at the intersection of three lines suggested some sort of artistic modification of the stream bed. The dark stream oozed slowly through the modified channel.

Titan was a slow world. A desert parched for the next rain, but everything moved so slowly that the stream continued to flow.

She had to be missing something. Some vital clue to explain the site. There must be something about it that she wasn’t seeing.

And when the sun passed behind Saturn, when night fell, they were going back to the colony. The others were busy right now packing everything up into the cat, getting ready to leave. They couldn’t stay. Rules, Mac wouldn’t allow it. Too dangerous to work through the dark. She was supposed to go back and spend her time reviewing the data already collected.

Five days ago Clara hadn’t even known about the site. None of them had known it existed, and she didn’t put any stock into Sanders’ notion that Terra Blackstone had known. Diaspora wouldn’t have kept it secret. She didn’t believe it. She’d had plenty of experience with paranoid conspiracy theorists dealing with her parents. God only knew why otherwise rational people believed such things.

The first images of the site had come from the jelly flock.

 

2

 

Jackie “Red” Tonner had burst into her tiny lab space, nearly tearing the flimsy door off in the process.

She yelped. Embarrassing, but he’d startled her with his big gangling frame bursting into the lab. Like her, he wore a standard black Diaspora workall, with bare feet. Tools and spare parts clanked in his bulging pockets. His stock of red hair was going every direction, as was his curly red beard. Jackie blushed and ducked his head.

He didn’t get the nickname from his hair color. He blushed all the time.

Clara pressed a hand to her chest. “Jesus! Knock before you barge in here!”

“Sorry. Really sorry.” Jackie thrust a tablet at her. “Look at this. Grabbed it out of the flock footage.”

She took the tablet and looked at the image. Greyscale, aerial image, which was what’d she’d expect from an image from the flock. The jelly flock was a bunch of brightly-colored jellyfish-inspired balloon robots deployed around Titan at different altitudes to study and monitor their new home. Each was equipped with a suite of tools to measure, analyze and photograph the environment. They swam through the thick air just like jellyfish back on Earth. And they worked in tandem with the half-dozen satellites orbiting the moon. Diaspora had sent them out with the full package to learn about the moon, thanks to Mac’s insistence on the support.

The image on the tablet was beautiful. A pattern of geometric lines and circles cut into the surface of the ice, around a small methane stream. It gave the illusion of avenues, and structures, of open public spaces and interesting diversions. Nothing as boring as a grid, it was a complex snowflake design.

Clara laughed and held the tablet out to Jackie. “Nicely done. It looks great, but it’s too complex. No one’s going to buy it.”

He held up his hands. “No, no. No! You don’t understand, it’s really real. You know?”

“Right. Look, I’ve got work to do, okay?”

Jackie shook his head and crossed his arms, hugging himself. “No, no. It’s real! That’s raw footage. I didn’t touch a pixel!”

She tipped the tablet, looking again at the image. “What are you trying to say? That this is actually out there?”

Jackie grinned widely, bit his lip and nodded vigorously. He freed his right hand and shook a finger at the tablet.

“You know what this means, right? I mean, I’m not crazy? I’m not! That’s artificial! There is no way that it is natural, right?”

A cool thread of fear ran along her nerves. A discovery like this, well, there weren’t words for it. It’d be the most significant find, ever, anywhere in the solar system. When word got out they’d be the center of attention in the solar system.

And if this was some sort of prank it could destroy careers and make them the laughing stock of the system.

She looked up at Jackie. “You’re not pulling my leg are you? I need you to level with me. If you’re joking around, fine, you got me and it stops now.”

“No!” Jackie blew out his breath and rocked on his feet. “It’s not a joke. Really. It’s real.”

He gestured at the tablet. “Swipe, come on. It’s not the only picture. There’s video too, if you want it.”

Clara swiped the image. Another picture, the same complex network of lines cut into the area around the stream, but the camera had moved closer. Swipe. Another image, the camera moving closer. The jelly bots instincts for interesting features probably drew it to the site. She swiped the other way, fast, flipping through the images.

A stop-motion parade of images in reverse, back away from the site, over a pair of small rises that hardly deserved the name of hills. The first image of the site only showed a small piece, but that’d been enough to attract the interest of the jelly bot.

She swiped back through to the close-up images of the site. The jelly bot circled around the site, taking pictures from multiple angles.

Jackie rocked in place and chuckled softly as she studied the images.

When she looked up he pointed at the tablet. “Load the video.”

A numbness, like she’d gotten zapped, filled her hands. They shook slightly as she pulled up the menus on the tablet and connected to her lab displays. She picked out the video files and sent the output to her holographic display.

Jackie jumped back as the hologram appeared like a floating table in the center of the small space. Clara rose and stood next to him.

Titan’s surface lay beneath them, as if they were on the jelly bot itself, flying over the orange hills. The view barely moved toward the hills and the tiny corner of the site visible.

“Increase playback four times,” Clara said.

Now the camera moved smoothly towards the hills with purpose, in a gliding sort of motion. The video was silent. Jackie breathed noisily. It didn’t matter. The view rose up above the hills, focused on the site. As it crested the hills the whole site was visible, spread out in complex geometric shapes from the stream. More on the far side of the stream than this side, but she saw lines that approached the stream and ran along it, while others cut right to the edge of the stream and then continued straight on the other side.

As if bridges had once spanned the stream.

“Scale,” she said.

Bright blue lines appeared over the orange surface and the playback stopped. She reached into the hologram, tapping one of the lines that approached the stream on both sides. A blue line appeared between those points. Just about four meters across. Plenty big enough for a bridge, except it was missing.

Following that logic, even if it was a big jump, suggested that these lines traced the path of roads. The circular pits at the intersections, buildings. The whole site wasn’t big, around a kilometer long, and it extended out away from the stream just over a kilometer. Big enough to hold quite a few buildings.

“Hide scale. Resume playback.”

The jelly bot camera flew closer to the site and then moved off downstream. It avoided flying directly over the site, but circled the area. On the far side Clara paused the video and looked at Jackie.

He burst out laughing.

She shook her head. “Who else knows about this? Have you told Mac?”

Jackie flushed and shook his head. “No, I mean, I wanted to show you first. That’s right, isn’t it? You’re the expert in xenobiology, right?”

Yeah. The expert in imagining what might exist, without knowing if it did exist in the universe.

“Sure. That’s right.” She took a deep breath and looked back at the site. “You did just right. We don’t want to spread word about this, not yet. Not until I have a chance to talk to Mac about it. He’s going to flip.”

“So you think it’s real, right?”

Caution reared its ugly head. “I don’t know. It looks amazing.”

A thought occurred to her. “Where is this? How far away?”

“Not far. A couple hundred kilometers from here. Isn’t that lucky?”

Suspicious was a more likely answer. What were the odds that they’d pick a spot so close to this site? Unless there were many of these sorts of sites around the planet, but so far none of the other jelly bots had picked up anything like this in the mapping. Or if they had, it hadn’t gotten flagged and tagged.

“Lucky, or it isn’t an accident,” Clara said. “You might not have done this, but it could still turn out to be a prank.”

“How?”

“I don’t know. Either way, we have to talk to Mac. Come on.”

“Now?” Jackie’s voice squeaked.

“Yes. Now. Someone else might look at the footage and then word’ll get out. We need to take this up the chain first.”

3

When Terra Blackstone and the Diaspora sent out the first launches to colonize the system they didn’t start close in with the inner system worlds. The first launches went out to the farthest reaches of the solar system. Dwarf planets at the edge of the system like Eris and MakeMake and Pluto. Small colonies under the most difficult environments imaginable, far from the warmth of the sun in the deep dark.

Next came the wave that went to the gas giants, to Neptune, Uranus, Saturn and Jupiter. Only then did Diaspora move on to the inner system.

There was a method to the madness. They wanted the colonies to come online within the span of the same year. The most distant outposts also had much longer travel times, in the days before Mercury started putting out solar sails and the creation of beamed power stations. The Diaspora’s transportation infrastructure wasn’t in place yet. And given the time involved, those early launches were the biggest, essentially flying colonies all on their own.

The Titan colony arrived ready to deploy on the surface. The main transportation ship, the Herschel, had remained in orbit and was still manned to help with the efforts below.

It was only now, months after landing, that the colony domes were finally coming to life. Vibrant plant life was filling the domes thanks to the fusion reactors that powered the base. Hydrogen was easy to come by on Titan, and they needed the power for heating and lights.

Mac had built his offices on the upper level of the main dome, a transparent-walled deck that looked out over the young trees below. Clara and Jackie were shown through to his offices by his aide, Brenda. He rose from his desk facing the windows as they entered.

At fifty-one, Mac was a powerfully built man. Not tall, but well-muscled and lean, corded and fit. He moved with easy grace in the low gravity. His graying hair was trimmed close to his head. He smiled warmly.

“Clara. Jackie. This is a surprise. How are you doing? Brenda said this was urgent. Did you find something?” He chuckled. “I’d love to find something that would trump Ceres!”

All of the colonies were eager to discover signs of alien life on their worlds. A biosphere existed below the surface on Ceres, not the most likely candidate in the solar system. Since then everyone wanted to find something more. They’d all been hoping to find some sort of non-carbon based life on Titan.

“It isn’t what we were looking for,” Clara said. “Jackie found something interesting in the jelly bot footage that you have to see.”

“Okay. Show me.”

Clara used the tablet and pulled up a clear image of the site, showing the complex network, the circular pool in the stream, and the other pits at intersections and other features. She handed the tablet to him.

Mac looked without comment. A muscle in his jaw twitched. He swiped through several images before he looked up.

“You’ve verified that the footage hasn’t been tampered with? We can’t have a hoax about something like this.”

“It’s clean,” Jackie said. “I checked twice, that’s all raw, unprocessed. Just downloaded in the link.”

Mac went back to looking at the images. Jackie chewed on his fingernails.

Out Mac’s windows was the interior of the dome. Bright lights hung from the structure to supplement the meager sunlight that reached Titan’s surface. They lived in greenhouses on the surface of another world. Odd, really, when you thought about it. Back on Earth Diaspora had built hundreds of similar habitats as high-end housing projects back before it reached the launch stage. Those projects had served as models for these habitats, letting them test out designs and ideas while raising money to help fund operations. Only one of the thousands of projects, patents and investments that had built the Diaspora Group under Blackstone’s management. Those Earth-based habitats had promised clean water and air, climate-controlled environments on a world dealing with the effects of global warming. Some of the most popular had been habitats in striking locations, where the ocean levels had risen, or the Sahara. Even the harshest environments on Earth were tamer compared to what they faced here.

Mac said, “Can we rule out a hoax by our own people? Could anyone have gone out and done this without our knowledge?”

“You mean out there? Outside?” Jackie asked.

Clara shook her head. “Look at the measurements, the size of the thing. It would have taken weeks, equipment, probably multiple cats. Plus days to get there and back. And did you notice how clean it is? Everything cut away and smooth, but there’s no obvious piles of ice left behind. No debris.”

“Maybe it was vaporized.” Mac tapped the tablet and handed it back to her. “Still, we need to check it out. I want you to pull together an expedition. We’re going out there.”

“We?”

He grinned. “No way I’m sitting here while the rest of you go have the fun. I am a scientist, remember? I’m coming with you. A small team for now. Let’s limit access to the files and details of the expedition.”

“That’ll raise questions.”

Mac shook his head. “Let them wonder. When we know something, then we’ll have a better idea of what to say.”

4

Mac only wanted four people on the initial team. Himself, Clara, Jackie and Neil Sanders, a big, quiet man with a knack for keeping equipment running. Sanders ran the shops that took care of the cats and other heavy equipment. Mac wanted him along to drive the cat and deal with any problems that might come up.

Clara had protested, arguing to include more members of the science and cultural teams to no avail. Mac wanted the team small. Officially the mission was a test case, a trial field expedition before wider operations were started. That was news which cheered the rest of the scientists and left Clara feeling rotten inside for hiding the truth from everyone.

God only knew what they were going to discover. The cat’s slow, steady motion was almost unreal as it glided along, treads carrying them across the frozen surface. Mac was up front with Sanders. Jackie was currently busy driving another jelly bot to the site so that they’d have two to help with the survey.

More and more she couldn’t shake the feeling that this was the most monumental discover in human history. She was glad to be included, but also scared to death that they might screw it up somehow.

Her glasses projected an image of the site in front of her, a virtual hologram of the surface built from the latest data on the site.

The day on Titan lasted for slightly more than fifteen Earth days, the same length as a Titan “year” as it orbited Saturn. Jackie’s news coming when it did meant that they only had about two full days left until night fell. It’d taken them the past couple days just to get out to the site. Two days to investigate and then Mac wanted them to pull out and go back rather than work through the night.

Even though it made sense it was frustrating. She studied the lines of the site, trying to figure out where to even start with the thing. The jelly bot had flown over around the site, staying out from the center thanks to its programming. If it had found a geyser, for example, they hadn’t wanted it to fly right over the geyser and get hit by an eruption, so instead the bots circled interesting features at what was a safe distance.

Mac had refused to have Jackie override the jelly bot and send it directly above the site until they arrived on site and could supervise.

The safest bet was to start further out and work their way in, studying the terrain all around the site. There might be other, less obvious features that they could damage if they rushed right in.

Clara gestured and a large semi-transparent donut-shape appeared over the holographic image of the site. It created a green buffer a kilometer out from the site, a half-kilometer thick. That was a lot of ground to cover.

Another gestured and a yellow donut-shaped region appeared inside the first from the outer boundary of the site out to the green ring.

A final gesture dropped a red region over the site itself.

Of course the site wasn’t circular, not even close. It spread out like a snowflake away from the stream, but unevenly reaching out in different directions. One particular set of lines ran out in a to the apex of a triangle, with a triangular space between them, and a circular pit at the intersection point which was well into the yellow region.

Clara dragged the circles, widening them out until the whole site was within the red circle. That left other areas within the red that showed no signs of any design. She pushed with her fingers and deformed the circles, pushing them in and dragging out until she had constrained the red region to the site, the yellow band around that, surrounded at last by the green band. The final shape was more amoebae-like than a snowflake.

As a guideline, it at least gave them some areas to look at first, and an avenue to explore. It provided a framework they needed. They wouldn’t have time to comb over the whole site before nightfall. They could move quicker through the green areas using the jelly bots. The yellow and red areas could be subdivided into sections, and each could be examined before moving forward.

Proceeding on that plan, they could penetrate into the core of the site quickly and still maintain isolation with the rest of the site and catalog anything they discovered.

She sent the image and data over to Jackie. “What do you think about this?”

Jackie’s hands moved as he accessed the image. He nodded. “Sure, sure. That’s good. That makes sense.”

“Can you program the jelly bots to start high-res scanning on the green area?”

“Beta isn’t there yet,” Jackie said. “It won’t get there until a couple hours after we arrive, it looks like. I could put alpha on it, though. If that’s okay?”

Clara nodded, already refocusing on her screen. “Great. Thanks. I’ll watch the feed for anything interesting.”

The last few hours she watched nothing. The jelly bot floated sedately around the site and took high-resolution holographic images of the green region. Her system filled in the updated images within the region.

Hydrocarbon sand, water ice rocks and no signs that any of it was disturbed. No tracks. No footprints. How was that even possible? Whatever had made the site must have left other traces but nothing had stood out in the images from the site already sent over. This was a higher-resolution pass. There had to be something.

5

Three hours later the cat slowed and stopped at the base of the small hills overlooking the stream and the site. It was well outside the safe region that Clara had defined. The cockpit door slid open and Mac came through in the main cabin.

“We’re stopping here,” he said. “I don’t want to risk taking the cat closer. At least here there’s some cover from the terrain between us and the site.”

“Cover from what?” Jackie asked. “It looks abandoned. Doesn’t it?”

“We don’t know anything about it,” Mac said. “Yet. We’re going to play this smart. Clara, what’s the plan?”

“Only two go out at a time. First trip. Thirty minutes,” she said. “I’ve defined search regions.”

Clara sent the image overlay to the general system, projecting a hologram on the wall screen. “Jackie has the jelly bot mapping the green area.”

“That’s alpha,” Jackie said. “The one that found the site. Beta will be here in twenty minutes.”

Sanders appeared in the doorway behind Mac. He crossed thick arms.

“Good work, Clara. You and I are going out. Let’s get dressed and ready to go.” Mac glanced back. “Sanders, you’re in charge here. If an emergency happens, contact the base first. Give them as much information as you can.”

“Got it,” Sanders said.

“Why would there be an emergency?” Jackie looked between them, hugging his thin chest. “Why? What would happen?”

“We’re just playing it safe,” Clara said. “I’m more concerned that we don’t accidentally mess up some vital clue. We could have used an archaeologist on this.”

“We don’t have any.” Mac crossed to the storage lockers and pulled out her suit and passed it over.

It looked more like a snow suit than a space suit. Specially designed for the Titan environment, to keep them warm in the absolute cold outside. Insulated boots, insulated suit. Light-weight, particularly in the low gravity. And unlike the rear-entry suits they had used up on the ship, these Titan suits were put on like any other insulating suit, pulling them on right over her workall and fastening them together.

While she and Mac dressed, Sanders and Jackie retreated back into the cockpit to give them room.

The last part, the helmet, was the most like a space suit. It fastened into the stiff collar on the coat and the inside had a thick insulated hood to keep their heads warm. They’d designed the suits to use outside nitrogen, warmed by the suit, and bottled oxygen. It was the same mix that they used in the cat and habitats and since they maintained the same pressure as outside, it wasn’t a big deal. Heat loss was more of a concern than anything else.

Clara finished dressing first, and Mac a second later. Her glasses projected a suit analysis and gave her green lights. She opened a channel to the others.

“I’m online. Are you reading me?”

“We hear you,” Sanders said. “You both look good. Have a nice stroll.”

“Synchronizing timer,” Clara said. The countdown popped up in the corner of her display. “Thirty minutes. Let’s go.”

The airlock was a simple design. They both stepped in, closed the door and opened the outer door. No complex system needed to purge it. After they were out the air in the airlock would be cycled to removed the traces of hydrogen cyanide.

When that door opened it was beautiful. The orange surface extended out from the cat, a mostly flat plain from this perspective, covered with pebbled water-ice rocks. She was closer to the door but hesitated.

“Go ahead,” Mac said. “You’re in charge out here. This is your discovery.”

“Thanks, but Jackie caught the footage first.”

Mac didn’t comment, and Clara stepped out. It looked like a big drop down to the surface but really, in this gravity, it didn’t matter. She floated down and touched lightly on the surface. Her feet barely made an impression.

What should she say? Anything? The moment passed. She bounced from one foot to the other away from the cat to give Mac room.

As he floated down Mac flapped his arms and tipped precipitously forward. He landed awkwardly and stumbled, but kept his footing.

“Add wings and we could fly,” Clara said.

“Tempting, but I think I might have trouble with the landing.”

He came up beside her and she tipped back to look up at him. A big grin spread across Mac’s face. He gestured.

“Lead on.”

Clara pulled up her display in overlay mode and walked around the cat and up the hill. It hardly deserved the name of a hill. It was a rise, a swell. Walking up it didn’t require any more significant effort than walking on the loose surface anywhere else. The powder orange surface wasn’t disturbed much by their passage, but when she shuffled around she could see the tracks leading down to the cat. The cat’s own treads had left a very visible trail that led off into the hazy distance.

While she walked she could almost forget that she wasn’t alone. The air tasted metallic and cold. She shivered, not from the cold as much as what she knew was right over the rise.

Then she was high enough to see the site spread out down below them, the far side hazy. Her overlay showed the ghostly regions that she had defined. She did a focus blink and hid the display. Right now she wanted to see it as it was.

The design was cut into the ice, mere centimeters in places from the look of it, deeper in others. Cut right down into the icy bedrock of the place. The lines looked, for lack of any other words, like roads. The pits the empty cavities left by buildings. Or was that only her human bias? The design was also beautiful. Maybe an artistic creation? A signature of some sort?

The stream bed through the site was natural, but not the circular pool where the lines intersected.

Whatever the explanation it was obviously not a natural phenomenon. Someone had created this mystery.

“Breathtaking,” Mac said. “It looks bigger in person.”

Did it? It looked small and isolated to Clara. One small indication of some other intelligence, but lonely. At least so far the jelly bots hadn’t found anything like this anywhere else on the moon.

A pulsing blue-green shape floated through the haze. The jelly bot, floating toward them, still within the green region that she had defined. Farther off, through the haze, was a dark spot floating in the air. That had to be the other jelly bot, coming to help out.

Actually, when it came down to it, it was unbelievable. “How can this be real?”

“What do you mean?” Mac said.

“All of it. How can this be our life? That we get out to Titan and discover this? I feel like somebody is about to jump out and laugh their heads off at our expense.”

“I get it,” Mac said. “Let’s take it a step at a time. If this is a hoax, it’s pretty elaborate. Who could have done it? Sanders already verified all of the equipment logs. We would have noticed if someone came out here and carved this out. And we’re the first people to come to Titan.”

Clara pointed. “Obviously not.”

She started walking down the slight slope toward the dark stream. Each step carried her closer. She reactivated the overlay and bounced on across the surface. Now that she was moving, the fear melted away. She wanted to see what was there. Mac was right, hoax or not, how was it done? Surely whoever did this left some sort of clue behind.

When she reached the overlay the color vanished, except the thin outline. Clara stepped into the space and stopped. She studied the ground ahead as Mac came up.

She activated the recording on her glasses and surveyed the ground ahead. Nothing to write home about. Shades of orange, with hydrocarbon and ice sand, harder clumps of water-ice rocks, all leading down to the stream itself. It could have been a rocky stream bed in the late summer back on Earth, with rocks surrounding the stream as it flowed slowly along. Except it was orange and the rocks were ice and the stream was methane.

Yet, it was all still very familiar. A slow, cold stream bed leading on into the site. From here the site was almost invisible. The closest lines were noticeable but the rest, were lost to perspective and haze.

“We need to document everything.” Clara focused on the ground and shared the overlay with Mac. “We’ll go side-by-side, and cover our way in. We come out the same way. ”

“What are we looking for?”

“Anything that doesn’t belong. A footprint.” Clara turned and pointed. Even though they didn’t leave much of a track, their footprints were still visible, disturbing the darker material on the surface to reveal lighter traces below. “Think how much a track like that could tell us?”

They moved together in silence. Her attention was all on the ground. Some of the water-ice rocks had a polished look to them, rounded, but this was essentially the stream bed. It suggested that in wetter times the stream was bigger. Maybe there were even flash floods at times. Orange hydrocarbon sand showed clear tear-drop drifts against the rocks. None of it looked disturbed.

“I’m not seeing anything unusual,” Mac said.

“Me either. Not yet. Let’s keep going. We don’t rush it. The stream might have washed out any signs that were out this far.”

They continued the survey. Jackie’s voice cut in on the channel.

“Uh, guys?”

“Yes, Jackie?” Clara answered.

“I’ve got both jellies on site now. What do you want them to do?”

“Continue mapping the green region. When they finish, send them into the yellow. I want an alert on anything that doesn’t fit. Are you watching the feed?”

“Yes. Sanders is helping me.”

“Good. Keep an eye on it. The detection algorithms on the bots might overlook something that would catch your attention.”

“Okay, okay. We’ll do it.”

Clara and Mac continued their own survey through the green band, with white lines on the overlay marking the boundaries of the area they had examined. With each step her insides tightened. They weren’t finding anything. Not a bit of trash, not a footprint, nothing. No clues on the origins of the site.

It was still early. Too early to despair, they hadn’t even reached the site itself, but her gut was telling her that they weren’t finding the answers she wanted.

They wouldn’t know until they finished surveying the site.

It took them ten minutes to cross through the green band to the yellow. There wasn’t enough time to reach the site itself, within the red band, before they had to turn around.

“Five minutes left,” Clara said.

“We can go longer,” Mac said. “We have enough air.”

“No.” It pained her to say it. “Mac, we can’t. We need our focus. We need to do this right. When the time runs out we go back, with the same focus we used going in. There might be something we see going back over the ground that we missed on the way in. Then we need to rest and review what we learned.”

Mac paused and turned to her, studying her.

“We’re wasting time,” she said.

Inside his helmet, Mac nodded. “You’re right. We’ll do it your way.”

Good. If she could only be sure that her way was right. They had to stay sharp. Stay alert. In an environment like this, with something this important, they couldn’t screw it up.

“Let’s keep going.”

Mac moved forward with a long, bouncing step. “Mac!”

He stopped. “What?”

“We keep the pace. We can’t afford to miss anything.”

“Okay. Sorry.”

Nothing about the passing terrain stood out from anything else she had seen so far on the moon. There was stark beauty in this dry landscape. Funny, that, it being dry when the rocks themselves were made from water-ice, coated in a hydrocarbon dust that turned everything an orange color. Not that it didn’t vary, there were lighter areas and darker areas, but overall a sameness about the place. A single palette like a monochromatic painting.

Still nothing disturbed the surface except their own footprints.

In the corner of her augmented display the counter spun down to the halfway mark and flashed as it reached the end.

“Turn back.”

Mac kept walking.

“Mac! We have to go back!”

“Can’t. I want to see it. Then I’ll go back.”

She didn’t move. Frozen to the spot while the timer ran down her time. She couldn’t leave him out here alone, could she? She took the first step and then fell back into the motions. She studied the ground. Hell, if she was going into the site, at least she wasn’t going to screw it up by stepping on evidence.

Mac chuckled and she wanted to grab one of the rocks and chuck it at him. Did the hydrocarbon dirt pack into clods? Her hands itched to find out.

She pushed the temptation back. One step at a time. Mac’s pace slowed until she caught up to him. Then he matched her stride.

“You want to see it too.”

She did. Of course she did. Comments were pointless.

Seen like this, the site looked even more like approaching a street. Straight ahead, on this side of the stream perpendicular to their approach was a straight line cutting through the ice, about the width of a two-lane road. Maybe ten centimeters deep, though that varied. The inner surface looked level, it was the material it was cut through that varied.

A red line flashed as Clara stepped out of the yellow region into the red.

“Uh, guys?” Jackie’s voice came over the channel. “What are you doing? Why aren’t you coming back? What’s going on?”

Clara flushed. She hadn’t even thought to tell them they were continuing. “We’re fine. We’re extending the mission.”

“Oh, oh. Okay.”

“Hang tight,” Mac said. “We couldn’t go back without getting a look at this place.”

Nothing unusual about the surface outside the “road” if that’s what it was. Clara stopped a meter away and grabbed Mac’s arm when he tried to continue.

“Let’s stop here. We’re close enough. Let’s survey what we can see before we go any closer.”

Mac pulled his arm free. “I’m a scientist first, I’m not going to destroy any thing.”

If she could count on that, they’d be back in the cat by now instead of pushing the excursion on the first trip to the site. Not that she blamed him. Going back when she had said would have been hard to do, if she was being truthful. He saved her from that decision.

“The cut is precision sharp.” Her throat threatened to close up. She inhaled the cold air and breathed out. “Clearly not a natural artifact.”

She reached up to rub her eyes and her hand hit the helmet. “Oh, my god!”

Clara laughed and reached out to Mac. He caught her arm. For a moment it was like she was going to float off the surface of the moon and drift away.

“Take slow breaths,” Mac said.

It didn’t make any sense. Why was he saying that? Then she heard it. Her breathing, harsh, sucking air. Oh god, she was hyperventilating!

“Slow, slow,” Mac said.

“Clara? Clara?” That was Jackie. “You’re heart rate shot up, what’s wrong?”

She closed her eyes. God. So embarrassing! She breathed in, and out. Mac held onto her. Kept her anchored. Her breathing improved. She opened her eyes.

There, right between them in the ground, was a quarter-sized hole. Perfectly formed. Clara tapped Mac’s shoulder.

“You okay?”

“Look down there.”

Mac moved back and bent forward. “Look at that. You’re recording right?”

“Yes.” Every bit of her embarrassment, but it was also getting this. “I can’t see how deep it goes.”

“Are there anymore?” Mac turned a bit, then pointed. “Right behind you, another one.”

“Where they there before?”

“I don’t know. I hadn’t noticed it. It’d be hard to see unless you’re right on top of it.”

“Let’s back out, carefully,” Clara said. “Don’t step on them. We need to review the footage and see if they were there before we got close to the site.”

“Agreed.”

Clara turned in place and took a careful step, picking her own footprints. No holes there. None others away from the site. There was the one Mac had pointed. And maybe one another meter or so farther down, but it was hard to see. If it was there, that was at least three parallel to the “road.”

It took a long time to get back to the cat. Her nerves buzzed with energy. At the airlock she bounced up, caught the edges and pulled herself inside. Mac floated up too, and they sealed the door. She stomped her boots. Bits of hydrocarbons fell away.

“That stuff’s going to get everywhere,” she said.

“Can’t help that.” Mac hit the button to cycle the lock.

As warmer air rushed in the hydrocarbons melted on the floor and dripped off her boots. The air continued a few more minutes and then stopped.

They moved on inside.

Clara stripped off her helmet as soon as she could. She sucked in the warmer air of the cat. There was a burnt sort of smell, from being outside? Sanders and Jackie crowded the hatch to the cockpit. Mac moved in and she stepped aside to given him room. He twisted his helmet free.

“So?” Jackie said, bouncing on his toes. “What was it like? What was it like?”

Sanders put a hand on his shoulder. “Settle down.”

The bouncing stopped but Jackie still had that eager-puppy look.

Cat tucked the helmet under her arm. “It’s hard to say. It’s really there, which is incredible, but I have no idea what we’re dealing with.”

“Ask Diaspora,” Sanders said. “Do you think it’s luck that this place was this close to our base?”

Jackie looked up at the big man. “What do you mean?”

Sanders’ shoulders rolled like a swell on the ocean. “I’m just saying. It the grand scheme of things, this might be a small moon, but it’s still pretty frickin’ big. All the places we could have landed, and we’re this close?”

“I don’t think Diaspora knew about this,” Mac said. “I didn’t.”

Sanders shrugged. “Just ’cause they didn’t tell you, doesn’t mean they didn’t know.”

“The mapping program would have found it sooner or later,” Jackie said.

“Right,” Clara added. “And we don’t know that there aren’t other sites around the moon. Not yet. Not until we’ve mapped every square meter out there.”

“Maybe so.”

Mac was unfastening his outer layer and it made her realize how chilled she still felt. The suit might keep them from freezing, but it was still damn cold out there.

She put the helmet down and started unfastening her suit too. “We’re going to rest, and then we’ll start reviewing our findings. Jackie, put the jelly bots into a spiral search pattern to the center of the site. I want them to record with everything they’ve got, highest resolution. We found some small holes along that roadway or whatever it is. I want to know if there are more, and how deep they are.”

Jackie’s head bobbed. “I’ll get on it.”

He ducked back into the cockpit. Sanders followed.

She pulled her boots free, then started shimming out of the suit. Mac was doing the same dance in the aisle. There wasn’t much space to move in the cat. It was sort of like an RV back on Earth, with spaces for living and working. Even side sections to extend and create more space when it was needed. Right now everything was pulled in, leaving them only a small booth and the racks on each side of the aisle.

“Maybe this is only the surface,” Mac said.

His eyes were distant, like he was looking off through the sides of the cat, and the hills beyond.

“Maybe there’s a whole complex dug down into the ice. Some of those pits looked deep. There could be more underneath. We need to get sonar out there too and see what we’re dealing with.”

“That’s a good idea. We can have Jackie run it while we rest.”

He sighed. “You’re right. Rest first.”

6

Rest didn’t come easily to Clara. She climbed into her bunk in the rack, one of the half-dozen along the cat’s aisle, hers was on the top. She sat, propped up by a foam pillow and displayed the live footage from the jelly bots, in two side-by-side windows. Nothing new there. Just the ground floating by beneath them. The cameras on the bot adjusted for its own movement, giving the image a steadicam quality despite the pulsations of its movement.

Clara swiped the images away and closed her eyes. It did no good. She was back out on the frozen ground, barely touching it despite her suit, like a drifting ghost.

The city, no, no. She didn’t want to jump to that conclusion but that’s what it looked like. This wasn’t like someone looking at footage from the old rovers on Mars and imagining that every rock was evidence of alien life and a NASA conspiracy.

This was real. It was really out there. Someone had come and had made those cuts into the ground outside. Roads or artwork, or some other purpose that she just didn’t understand, it didn’t make any difference. It was real. And they only had a limited window right now to figure it out before night fell.

That was it. Once night fell, once they went back to the colony, then it wouldn’t be her’s anymore. It’d belong to everyone else. Word of the discovery would spread. For people like her parents it would be adding fuel to the fire. Things with Earth had gotten bad enough already. They’d launched the Lincoln against Diaspora on the Moon. Selene Martinez, director of operations on Earth, had managed to get off the Diaspora personnel and their families but that only made the preppers and conspiracy theorists more sure than ever of their “facts.”

Except that maybe this time there really was an alien city. City or not, humans didn’t create that site out there. They were the first people to reach Titan.

Her timer rang. Rest period was over. Time to get back to work.

7

Clara rolled out of her bunk. Sanders appeared in the cockpit door.

“Good, you’re up. You want the wings extended now?”

“Yeah. That’d be great. Let’s get to work.”

Mac slid out of his bunk. He didn’t look like he had rested any more than she had, and was holding a tablet in his hands.

“Clara, look at this. It’s from the survey.”

She took the tablet.

The wire-frame view of the site showed the complexity in great detail, everything measured and rendered in full dimensions. What was more attention grabbing, was how the site extended down into the surface. She zoomed in on the section that they had visited, which was only one small piece of the whole.

The small holes they’d found extended straight down into the ice almost two meters and just stopped. If they continued on at all, the scan didn’t show it. She rotated the view and saw that the pits also extended down into the surface at varying lengths and there were other parts that extended off of the lower levels. Passages? The jelly bots scans didn’t reveal how far the passages went and they hadn’t yet scanned the entirety of the site. To get a full picture, they’d have to go on.

Mac reached over to the tablet. “Look at this.”

The image zoomed in on a region within the site. A jagged crack cut across one of the “roads” and met with others, forming a radiating pattern of cracks. Looking at the wire-frame display it was clear that the whole section was concave.

“It’s collapsing.”

“That’s what it looks like,” Mac said. “That suggests that there’s something underneath. A chamber of some sort.”

He tapped the screen, zooming in on the nearest pit. “We have to get back out there and check out those passages.”

“We’re not equipped for that.”

“Come on, you can’t tell me that you’re not curious.”

“I didn’t say that.” It’d be a lie if she did. She was dying to see what was down there. Maybe there were answers. And so help her, she did want to see it all first.

“Let’s wait and see what we can turn up on the sonar. And Sanders is extending the wings so we’ll have some room to work. We get as much information as we can and then we decide if it’s safe to go in.”

“What if that collapses the weakened section?”

“Better that it collapse now than when we’re inside. I don’t like the idea of going in blind.”

“Fine,” Mac said. “Let’s get to work then.”

8

The next three hours were busy. Sanders extended the wings on the cat, which gave them space in the main body of the vehicle to pull out compact work areas. There were four stations altogether. She, Jackie and Mac took the stations and went to work exploring the site remotely. Jackie and Mac each took one of the jelly bots while she handled the sonar survey herself with the sonar drones.

Each drone was a squat robot shaped like a mushroom cap. The three of them trundled out to the site, rolling on three spherical wheels that bumped and wobbled across the surface but their low center of gravity kept them stable. She positioned them in an equilateral triangle around the site.

“Ready,” she said when the bots were in place. “Commencing sonar readings.”

Each bot sent out high-frequency pulse. The pulses were picked up in turn by each of the other two bots, processed and sent back to the cat to build up a complex picture of the sub-surface environment.

Combined with the jelly bot measurements, the model of the underground complex grew quickly.

A network of passages connected the pits around the site. The tunnels ran straight, intersecting and creating a whole network similar to the lines on the surface, but not identical. The paths weren’t the same, they didn’t line up together.

Mac whistled. “Look at that! There’s a whole outpost down there.”

Jackie laughed and pointed at the hologram model floating in the center of the cat. He slapped his leg. “Look at it! It’s beautiful!”

Maybe so. She shivered. Each time she looked at the site she had to reminder herself that humans didn’t create it. That was the thought that kept her nerves on edge. What sort of creatures came here to Titan and created this? Where did they go afterward? There wasn’t any indication that they were still here. From what they’d seen so far, the site was abandoned.

More details poured in from the next pulse. The image of the pathways was refined. There were chambers, and a big one sat right underneath the cracked region that Mac had noticed. It was large, round and connected to four of the passages. It looked like some sort of underground hub, with a domed ceiling.

Sanders came out of the cockpit. “That’s what’s under there?”

“Yes,” Clara said.

“Glad then that we didn’t drive any closer. I wouldn’t want to risk the cat on top of that.”

“The cat doesn’t weigh as much on Titan as it would on Earth,” Jackie said. “I doubt it would cause a collapse if we drove across the site.”

“Yeah? I’m not trying that. You want to do something like that, pick someone else. ”

Mac laughed. “Look at that! It’s incredible! Right out there is proof that humanity isn’t alone out here. Someone else has been here before us.”

“And left us with a big mystery,” Clara said. “Why do all of this? And where is any sort of structure. This looks like it is all just cut right into the ice.”

“We cut into the ice to build our colony,” Jackie said.

“Yes, but we still put a structure into place. We didn’t go walking around outside in our birthday suits.”

Sanders shrugged. “Maybe they considered this homey weather?”

“But there’s nothing there! Lines cut into the ground, pits, the sonar shows the shapes of the passages underneath and they look much the same. Straight passages connecting the different chambers and pits that open to the surface.”

Mac shook his head. “We won’t know what’s down there until we go take a look.”

“If there was any way for someone else to get here, I’d think this was a hoax,” Clara said.

“It isn’t a hoax,” Jackie said. “It’s real. It can’t be humans that made it.”

“Maybe it’s like those ancient aliens people talked about back on Earth,” Sanders said.

“No!”

All three men looked at her. She rubbed her eyes. “Look, let’s not even suggest that, okay? The people back on Earth that believe that sort of thing, they’re going to go crazy enough as it is. This is going to fuel the whole conspiracy ideas about Diaspora.”

“What if they’re right?” Sanders gestured at the hologram. “We know people didn’t create it. Can we figure out how old it is?”

“We can test the levels of hydrocarbons in the excavations,” Jackie said. “With our observations on hydrocarbon deposition rates, we can get a pretty good idea how long ago it was made. It can’t be very long, though, can it? Otherwise it would have been buried already, right?”

“Titan’s a slow world,” Clara said. “It might be older than we think, but get on that. Mac and I will suit up to go back.”

9

They retraced their steps back to the site and made better time. They weren’t carefully studying every centimeter of the ground this time. This time they wanted to get to the site and reach the nearest of the pits. Their target was a circular pit some ten meters across. Two passages connected to the lower levels, and more importantly, it was on this side of the stream.

Clara dragged a sled behind her loaded with gear for the trip down into the pit. The passages were four meters down in the pit. They had ropes and other climbing gear with them to make the descent. Mac dragged a second sled with additional climbing gear and even more sample containers. They’d packed everything that they could think of onto the two sleds and still the piled sleds hardly felt like anything to drag. Back on Earth each probably weighed a couple hundred pounds and here they were only thirty pounds or so.

Coming over the hill, seeing the site down below cut into the orange landscape, brought it all back. The reality of it. How many times had she heard her father talk about ancient astronauts, visitors from space that would return some day. A bit of doubt stirred and twisted in her mind.

Could these be the same aliens?

No. She didn’t believe that. Even though this was real, it didn’t make the stories back home real too. There hadn’t been any significant evidence on Earth, at least nothing that wasn’t easily explained by more rational reasons.

Here, though. This site was unique. Proof that another intelligence had been on Titan. The fact that it was a geologically recent site, and the lack of any evidence so far for endemic organisms, it strongly suggested that whatever, whomever had created the site had not been native to Titan. This wasn’t the Titan equivalent of Stonehenge or the great pyramids.

Before she knew it they were back at the first “road” in the site. She moved carefully between the quarter-sized holes and stopped.

“Go ahead,” Mac said.

The edge was sharp, cleanly cut, but there was orange hydrocarbon dust on the bottom. Clara knelt on the edge and poked a gloved finger into the dust. It barely came up to her knuckle. She pulled out a skinny probe and poked it down into the hydrocarbons. Jackie had coated it with an adhesive to collect a sample, and measure the depth. She lifted it carefully straight up. A faint orange haze clung to the bottom of the probe. She capped it and returned it to the pouch on her suit.

“Okay. I’m stepping onto the cut now.” Clara stepped down, it was an easy step.

The surface beneath her boots was smooth, but not slippery. The icy surface wouldn’t turn slick unless there was a methane rainstorm and those were rare, as the nearly dried-up stream showed.

“It’s hard beneath my boots. Feels perfectly smooth.”

Whatever had cut this had melted and smoothed the surface out. Instant road, made of bedrock. Stable, long-lasting. Maybe not a road by design, but it would make a good road. She pulled her sled down onto the road. The edge here cut through mostly water ice rocks. The sled didn’t even leave tracks until it hit the road surface and disturbed the dust.

Mac stepped down. He laughed. “I was half-expecting it to be slippery.”

Despite the cold air in her helmet, the rock-hard ice beneath her feet, the orange color of everything made it feel more than ever like a trek along an empty desert road. Except this couldn’t be a road. It was wide enough, but off to the right was another “road” that intersected this one at a sharp angle. Who built roads like that? At least not for wheeled traffic.

Her display tracked her position against the map. The intersecting lines looked more like a complicated geometric snowflake than a map of any sort of roadway system. Even though there were pits at the intersection points, those varied in size. The spaces in between the lines were unaffected by the creation of the site. How do you dig out that much material without having it disturb the rest of the ground?

“What do you think happened to the material removed?” Clara moved to the edge of the road they were walking down and pointed at the ground.

“Look at that, undisturbed, as far as I can tell. You can see the water-ice rocks cleanly sliced by whatever cut into the ground but it doesn’t look like they moved at all.”

“Vaporized?” Mac suggested.

“If that happened, wouldn’t the escaping material have disturbed the surrounding landscape? It suggests heat, which would have deformed the whole surrounding area. It should look like a giant slagged area, melted and refrozen, but it doesn’t.”

“One of the many mysteries, but we have to keep going.”

He was right. They didn’t have unlimited time. The plan was to spend no more than two hours exploring the site. Longer than she had originally considered, yet she also knew how hard it was going to be to head back to the cat. If they got too tired it might lead to dangerous, potentially fatal mistakes.

Following this line took them closer to the dark, sluggish stream flowing along the shallow gully. It spread out among dark water-ice rocks. Hard to keep things straight, that the stream was liquid methane, that the rocks weren’t silicates but water-ice. It looked like a slow-moving stream back on Earth running through a mostly dry stream bed in late August. Without all of the trees and brush along the rocky bed. Instead, a barren orange landscape with a hazy, orange sky.

A dark jellyfish shape pulsed and swam through the haze just ahead. That was red, the jelly bot that Jackie was bringing to help them on the expedition, but it added to the unreality of the scene.

Titan wasn’t Earth, no matter what superficial similarities they shared.

They reached the line intersecting the one they were following at a thirty degree angle. Did that have significance? How could they tell?

Clara stopped to look at the sharp point where the lines came together. Perfect, sharp with no unevenness. It really did look like something removed the surface within the “roads,” just stripped it away in an instant without disturbing anything else.

Or ate it away.

She ran her gloved fingers along the smooth sides. At the top of the cut the ground crumbed at her light touch. Sand drifted down onto her fingers. The broken edge disturbed the perfect line.

“Shit.”

“What?”

Insider her helmet, Clara shook her head. “Sorry. The edge crumbled away. I barely touched it.”

“Not as many rocks here.”

She straightened and dragged her sled around to the other side. “Let’s get to the pit.”

A few minutes later they reached the target pit. Both of them stood at the edge and looked down.

The pit dropped into darkness. Clara turned on her wrist-lights and pointed at the pit.

Smooth ice walls, like polished stone. From the map this pit dropped down fourteen meters and had two passages that connected to the lower portions. One passage was just over three meters down, the other at forty degrees around the side from their position. Each passage was about three meters high and the same distance across, cylindrical in shape. Good-sized passages, at least, no crawling about in tiny tunnels. It was interesting that there weren’t smaller passages showing in the sonar maps. All of the passages were the same size.

Clara turned to her sled and pulled open the first compartment where the climbing gear was stowed. “Let’s get anchored and get down there.”

Mac went to work without comment.

Clara used her system to pull up instructions, following them carefully as she set the anchors and prepared for the descent. They’d trained on it before leaving Earth, back in the basic training that all of the colonists undertook. Survival training, necessary skills for working in extreme environments, and all of that sort of thing had been required. Still, it didn’t hurt to have a heads-up display reminding her of each step.

At last secured, roped in and ready to go, she looked over at Mac. He was finishing up.

“Ready?”

“Ready?” He gave her a thumbs up and the light came on his helmet. “See you at the bottom!”

He backed up and walked right over the edge. He dropped, slowly and laughed. “Too bad training wasn’t this easy!”

Clara didn’t look down as she stepped over the edge. She was ready to fall and it didn’t happen. She kept her feet on the smooth face of the wall and took the first two steps. With the low gravity it was no effort at all. She let out the rope slowly and walked down the wall.

Her helmet light reflected back at her from the polished surface of the wall. The wall looked like the surfaces of the lines above. Sealed tight. Put a lid on this thing, it’d probably hold an atmosphere. Of course if the air wasn’t cold, the surface would melt.

The descent continued until an opening appeared beside Clara. She kicked off and swung slowly over into the opening and landed lightly on her feet. She moved aside to give Mac room and a moment later he appeared beside her.

Their lights showed an empty passage ahead. Nothing artificial, the surface was the same sort of melted and sealed material as the lines above or the pit.

“Nothing.” Mac’s tone was disbelieving. “Why did empty tunnels?”

It wasn’t an accident. The passage was perfectly straight, smooth and bare from the orange hydrocarbon dust except traces that were right in the entrance. Clara’s lights played over the walls, revealing sedimentary layers of varying oranges. The passage was round, but it gave them plenty of room to walk. It could have been a rounded sewer tunnel at one point, except it didn’t go anywhere to empty anything out.

“It does give you a look at the geologic history.”

“That’s great, but right now I’m more interested in the ones behind digging this out.”

They were all like this, all of the passages. Clara felt it in her gut. Whoever had created these passages and the lines above, for whatever reason, they were gone. All of this was like a footprint left in the sand. Pack it in, pack it out, must apply to aliens too.

“We don’t know that is the case,” Clara said, not believing it. “Even if it is, we won’t know until we have a chance to check out all of the passages.”

“Let’s get on with it, then.”

“Jackie? You reading this? Bring down the jelly bot.”

“Yep, yep. It’s right behind you.”

“Record everything,” Clara said.

They both unclipped and walked into the passage, then looked back. A few seconds later the undulating shape of the jelly bot floated into the passage opening. It drifted into the tunnel. It was bigger in person and looked disturbingly alive. Clara and Mac moved against the sides of the passage.

The jelly bot pulsed and swam forward into the passage. It’s motion made soft sighs in the air. The trailing tentacles were all recording devices, sampling the air, imagining its surroundings and taking dozens of other measurements. Clara waited until it was a couple meters ahead and then followed it inside.

The passage continued on without break or interruption. Nothing unexpected from the sonar readings. Ahead was the first chamber, a large rectangular shape.

It was, predictably as empty as the passage. Mac swore.

“What’s wrong?” Jackie asked.

“It’s empty,” Clara answered. “Like the passage, like the site above. Whoever they were, they’re gone and took everything with them.”

“There’s a lot of the site left to investigate,” Jackie said. “We don’t know yet.”

It was an echo of her own words, and she still didn’t believe it. They left and they took their toys home. A good practice, really.

“I’ll take some surface samples,” Mac said. “Maybe there are microbes left behind.”

Good idea, if only to rule it out.

While Mac worked, she walked out into the chamber. It was large, round, dark and empty. Cold. Her suit did a good job of keeping its internal temperature above freezing, but it was still cold. And the processed nitrogen from outside was still cold. The air coming into her suit was icy. That was a detail they could work on improving, although it did give a clear reminder of where she was right now.

Titan. A whole new world, in a chamber created by non-human intelligences. If that wasn’t incredible, she didn’t know what was. Sure, the conspiracy theorists, her own parents, would imagine all sorts of stories when the news broke. That Diaspora knew about the site before the colonists landed, like Sanders had suggested. That there was alien technology present, and Diaspora had taken it to use in their undeclared war against Earth. Or that they were all in cahoots with their alien overlords bent on dominating the Earth.

The truth was less exciting and more mysterious. Someone had visited Titan before them, created this site, and then left, taking everything with them.

The jelly bot drifted around the chamber. Another passage led off the left side of the chamber. Clara walked across the empty space and looked into the passage.

Indistinguishable from the one they’d used to get here. Bare, empty, and unmarked.

“I’m done here. Anything interesting?” Mac asked.

“No,” Clara said. “It isn’t different than the passage outside.”

“So we move on?”

“We move on.”

They walked into the next passage and kept going. The next chamber they came to was also round, but smaller, with the passage continuing on the opposite side. Otherwise no different than the one they had left. The jelly bot drifted through the tunnels ahead of them, recording everything.

When Clara’s timer sounded, it was a relief. “Time to head back.”

“Great,” Mac said. “My feet are freezing and I’m tired. Let’s get back.”

Nothing changed on the way back. They got to the mouth of the passage, clipped into the ropes and walked right up out of the pit. And then they walked back to the cat.

10

That evening they sat around the table in the cat, over plates of reconstituted spaghetti Mac had prepared. The garlic smell and the spicy heat were welcome distractions from the discouraging results of the day.

“What’s next?” Sanders said.

Mac twirled his fork in the pasta. “I’m sure there are experts that will trip over themselves for a chance to wander around this ghost town. I say we let them.”

“I’d like to go out,” Jackie said. “I want to see it myself.”

“Be my guest,” Mac said.

“I’ll go too,” Sanders said. “Empty or not, that’s history out there, man! I’d like to see it before Blackstone makes it off limits.”

“She’s not going to do that,” Clara said. “If anything, they’ll give us more resources to explore.”

“Maybe, or maybe they already know about it. Maybe they stripped it before we got here.”

Clara shook her head. “Paranoia doesn’t help, and it doesn’t make sense. If they sent another expedition out here, we’d know. And even if they did know about it, what did they do to keep it hidden?”

“Right!” Jackie’s head bobbed. “Right, I mean, they could have covered it up, couldn’t they? If they could take everything away, they could have removed all traces of it. Why leave anything?”

“Maybe they didn’t have time,” Sanders’ shoulders rolled in a slow movement. “You’ll have to ask them.”

Clara let the conversation drift around her and focused instead on her food. She pushed the pasta around on the plate, making lines in the sauce. The lines intersected and crossed. She scraped and twirled her fork, making a hole. A mold for whatever had been taken out? Maybe there had been something filling the spaces. If it had been a city, an outpost of some sort, then maybe there had been buildings. Things that been in the places that were now empty?

11

The next morning Sanders and Jackie went out and spent two more hours in the site, wandering around the empty passages without finding anything. And the whole time the jelly bots were now exploring the site too, looking for any anomalies, anything that might explain what it was or why it was here.

Nothing.

Clara spent the whole day reviewing the footage and the data gathered. All the materials at the site were native. The actual surfaces showed signs of being bonded together, by heat or some other reaction, but whatever had done it had done it quickly. As she’d expected, the walls were air-tight, which suggested that they had contained some sort of atmosphere other than the native atmosphere, but none of the samples taken showed anything except native gases in the usual proportions.

Mac speculated that there had been some sort of lining within the passages, like an inflatable habitat that the aliens deflated and took with them when they left. If so, it hadn’t left any trace.

And why make it so complex? There didn’t seem to be any pattern to it that she recognized.

12

After dinner Clara retired to her bunk and pulled up a holographic overlay on her glasses of the site the way Jackie had displayed it, with the wire-frame showing details they had gathered.

She shaded the wire-frame. Now the shapes had more substance, but they were hollow and empty. She inverted the model to fill the empty spaces instead, stripping away the rest. A solid complex below, the lines radiating around the site above. She focused on the stream and where the lines ended before the stream and seemed to continue on the other side, she pulled out the surface to bridge the stream. Then she pulled up on the bridge slightly, warping it into a stable arch.

That unified the site. The placement of the bridges didn’t make much sense, but it wasn’t any stranger than the rest. It was all speculation anyway, but at least it connected things. The roads looked like solid avenues, with bridges spanning the stream. Whether or not that was the case, she had no way to know.

In for that much, she might as well carry the speculation farther. It was probably a pretty reasonable assumption that the aliens couldn’t breathe Titan’s atmosphere. Maybe somewhere on, or in, this moon there was native life, but nothing led her to think that the builders of the site were native. The site was isolated and contained within itself. Almost like an ant colony.

What if that was the case? What if the lines on the surface weren’t roads like she was thinking, but passages? She expanded each of the roads, pulling them up to match the dimensions of the underground passages. She replaced the bridges with the passages crossing the stream. It really made the stream seem irrelevant, except for the pool that happened at one of the intersections. The shapes rotated in front of her, a complex, interlocking structure on two levels. No symmetry there, but maybe the aliens didn’t look for symmetry the way humans did. Humans liked bilateral symmetry and repetition. This shape, it looked more about the intersections.

Almost like a three-dimensional model of a molecule.

Clara’s breath caught in her throat.

Could it be that?

She stripped away the information about the ground surface outside and was left with the crisscrossing designs of the lines and the circular intersections. She dropped in spheres at each junction.

Even more like a molecule now. She rotated it and turned it. It wasn’t complete. More like a simplified short-hand to the actual structure.

Or a map.

13

Everyone was busy when she left her bunk and suited up. It was against the rules to go outside by herself but Mac wanted to pull up stakes and start back after they rested. Night was coming and he was frustrated with the site.

She had to see it again for herself.

Now, standing at the top of the hill and looking at the site, she called up her model. Was she missing something, could this be the answer?

The software adjusted for distance and perspective and settled the model into place. Blue, against the orange background.

Thick lines spread out across the Titan landscape. Add in the pits and the angles and new lines formed at angles, further connecting the intersecting points.

Mac had given up trying to call. He’d be out here soon.

Clara moved her hands, manipulating the model at a distance. She narrowed the lines down to simple dotted lines, like a string of bright blue Christmas lights. That left the spheres.

“Darken the view,” she ordered. “Simulate nightfall.”

The orange backdrop faded away to a darkened, ghostly landscape lit by starlight.

Stars.

She accessed menus and pulled up models. “Replace spheres with simulated stars. ”

Bright light pierced her eyes. She squinted. “Reduce size and illumination to ten percent.”

The brilliant display faded. There were stars, bright glowing stars, connected by a network of dotted blue lines.

“Clara!”

Mac’s voice behind her, distant still.

Clara studied the image. It felt right. A map of stars and connecting lines. But what stars? What were they trying to tell us?

If it was a message there was a key.

She looked at the circular pool in the stream. That was an unique feature. She pulled up star maps and focused on the Sun. If the pool was Sol, then….

Clara rotated the star map. The nearest star was actually three stars, Alpha Centauri and its companions, which made the nearest intersection Centauri. She swapped the generic star simulation for a model of the Centauri system. She connected the model to the star map database and instructed the system to populate with other matches.

The star field changed. Large and small, stars bloomed into place around Sol at the center of the stream pool. All the pieces snapped into place, connected by the dotted blue lines.

Mac huffed to a stop next to her.

“Clara, what are you doing?”

“I’m sending you an augmented view.”

“What?”

Clara sent the view to him.

He was silent. “Is this?”

“It is,” she said. “The site is a map of star systems spreading out around us. It isn’t to scale. They’ve pulled them closer, suggesting the relationships without worrying about the details. It’s like a graphic, showing the various worlds, without any details. The one thing they did do was put Sol in a noticeable place, using the stream as a landmark to draw our attention to it.”

“Why do it this way?”

“I don’t know, a test to see if we could understand it? The site is a three dimensional sculpture, a representation that uses the empty space as much as the spaces they modified. It might not even be for us, but a marker showing the worlds they’ve visited.”

“But which one did they come from?”

That was a good question. The stream cut through other lines, but no other intersections. None of the other intersections had any distinguishing marks. Some varied in size, but that might designate the type of star, or the size of the solar system?

Then she remembered. The first line that they had walked on, it was marked with small circular pits, quarter-sized. That line ran between two stars, neither one Sol, but at the intersection another line ran off to Sol. She checked Jackie’s model. The bots hadn’t found any similar markings anywhere in the site.

She highlighted the stars at each end. “This line was marked, remember the small holes we saw? They don’t show anywhere else in the site map. It could be an indication that one of those stars was their home, or indicate something particular about that journey.”

“You’re suggesting that they’ve been to all of those stars?”

“It fits the map.”

“It’s going to sound like we’ve found a crop circle on Titan that leads to the alien home world. No one is going to believe it.”

Except her parents. It’d no doubt panic them when they found out.

“That’s their problem,” she said. She gestured and collapsed the image.

The site lay as before, at the base of the hill, along the stream. Mysterious. Made by inhuman hands, by beings that could apparently travel between the stars.

Terra Blackstone had said before that she planned for the Diaspora to continue, to reach out to other worlds entirely. There was Eris and the other projects designed to reach outside of the solar system. People that were willing to stand on the precipice of interstellar space and face that deep, deep darkness.

When word got out about the site, they’d know that they weren’t alone. Other minds were out there, reaching out. Whether they left this site as a marker, or an invitation, or even a warning, it was going to change everything.

“It’s a great discovery,” Mac said. “Congratulations. We still need to get back.”

Clara turned away from the site. “I’ve got my questions now. Let’s go home.”

Together, they headed back down to the cat.

13,268 words

Author’s Note

This story marks the 7th weekly short story release, and the 7th Planetary Bodies story. Saturn’s impressive ring system and the cloudy world of Titan has always captured my imagination. It’s a moon unlike any other with a dense atmosphere, liquid lakes and streams and a complex geology. I was very excited when the Huygens probe parachuted down to the surface.

I’m releasing each of these stories, one per week, here on my website. Eventually I’ll do standard e-book releases when I am satisfied that I can create the cover art that I want for the books. In the meantime I’m enjoying these weekly releases.

If you’re interested in longer works, feel free to check out my novels through the series links at the top of the page. Check back next week for another Planetary Bodies story. Next up is Uranus Exposed.