“Mars is full again.”

“What?” Gabriel said. There was nobody else in the buggy with him, and it didn’t sound like anyone’s voice over the comms.

“Mars is full. Come to me.”

Gabriel sighed and fixed his eyes on the prize ahead of him. An impossibly huge dust cloud hung in the thin Martian atmosphere. That dust cloud marked untold prosperity for the people of Mars, and the result of almost two decades of work and planning.

Life on Mars has some natural constraints. There’s only so much oxygen, so much nitrogen, etc. Those can be overcome; there’s always more rock, and modern chemists could do things that would amaze the ancient alchemists. The biggest constraint is water. All the polar ice had been captured and carefully stored. Every time someone found new water was a day for celebration. Every drop of water was protected and recycled using increasingly efficient methods, and populations, both human and animal, were carefully monitored.

So when an astronomical outpost spotted a water-ice comet that was falling out of the Oort cloud towards the sun all of Mars coordinated. Such a comet would be little more than a drop in the massive oceans of Earth, but those were still radioactive. And hauling millions of tons of water from one planet to the next prohibitively expensive, even if the Terrans would allow it. This was water that, with a little course correction, would be delivered right to their door.

The plan had worked. The comet had struck Mars more than two thousand kilometers from the nearest settlement. It was probably the first time people had ever celebrated an earthquake. Or a Mars-quake. Once this water was claimed and purified and added to the cisterns Mars would, indeed, fill up a little more.

And now Gabriel was in the lead, a full day ahead of the huge bevy of reclamation vehicles that were racing to carve the comet up and capture its water before it could sublimate off back into space. A few spacecraft were ahead of them, starting on the construction of a magnetic field around the comet. But lifting heavy dome panels was prohibitively expensive compared to just driving them across the intervening land. Gabriel’s job, as ever, was to make sure everyone behind him had a safe path through the desert.

The desert.

That was a dangerous thought, right now.

There are three ways you can stop being an Explorer, Gabriel well knew. As one of the oldest and most successful he’d seen colleagues take all three.

The first was the one everyone expects: you get caught in a storm or a freak rock slide and you’re done. Mars is unforgiving and hard to cope with. If it weren’t there wouldn’t be any need for explorers. The Explorers call this “taking a wrong turn” as in “What happened to Ilena?” “She took a wrong turn a while back at Ilena’s Pass.” “That why they named it that?” “Yep.” And then they’d both get drunk in her memory.

Thanks to the Martian Observation Management Network (Rightly accused of choosing their name so that it could be abbreviated to “MomNet”) it is increasingly difficult to get that lost. Your suit will tell you if you’re getting too far away from your buggy, and if you don’t turn around your buggy will come pick you up, the whole time delivering a lecture on responsibility from someone in MomNet. Storms are tracked, buggies and suits have airbags…it’s still possible to get into a bad spot and die, but it’s much harder.

The second way is to find a place or a person that catches your eye. You set up a tent and head back there frequently, and then you build a small dome when the tent starts looking ragged. Your fellow explorers understand and when they’re nearby they help you out, and eventually you just accept it.

The third way is the one people rarely talk about. When they talk about it all, Explorers call it “Going to the desert”. It doesn’t happen often. But every once in a while an explorer gets an odd look in their eye, and drives out into the desert. When they’ve gone far enough they get out of the buggy, walk away from it, then open their helmet.

Because of the dry near-vacuum of Mars, their bodies are always well preserved, and the doctors can give you a long list of things that don’t cause Explorers to do this. It’s not a bacterial infection, or if it is its a bacteria that leaves no traces. There’s no cerebral swelling, no sign of brain cancer, no abnormalities in diet or blood flow. Physically they’re almost always in perfect shape.

Because of the nature of exploration it’s hard to ask people who “know them best” what might have made this happen. Nobody knows an explorer best, except maybe the other explorers. Nobody can explain why the method of suicide is always the same. The only behavioral connection is that two people who went to the desert had written “Mars is full” in the sand next to their buggy.

And now someone was telling Gabriel that Mars is filling up. To be honest, it was a thought he’d had a number of times. He glanced back over his shoulder at the huge convoy following him. One day. There was one day’s worth of space between him and…them.

Gabriel wouldn’t call himself anti-social. He got along well enough with people. In small groups. If they were people he liked fairly well. He didn’t dislike other people; he just got tongue-tied around large groups. He wasn’t good at telling jokes and saying witty things. If people were willing to listen he was a master storyteller and could hold a group spellbound, his plain voice and unaffected mannerisms complimenting his stories of the world outside of the domes.

The buggy’s lights came on as the sun set. Gabriel stopped the buggy and set up camp. Behind him the convoy did the same. Gabriel had already charted this area, but you can’t smack a comet into a planet without some tectonic changes, and driving at night was dangerous enough as it was.

His comm beeped as he finished getting his tent inflated. “You made good time today, Shepherd 1,” a voice crackled in his ear. His visor flashed “Artist 5”, one of the star craft that was “painting” an electronic net around the comet to keep the water on Mars.

Gabriel kind of hated call signs. His name was Gabriel, the pilot of Artist 5 was one of his oldest friends, Cara.

“Mars is full again…I mean, thanks, Cara. You sent me some great terrain scans, made it easy.”

There was a long silence on the comms. “Gabe, what did you say?”

“I said thank you.”

“Before that.”

“Nothing, nothing.”

Another pause.

“Maybe I should get Artist 7 to cover my zone and fly out to your position. It’s getting kinda lonely up here.” Cara’s voice was overly casual. Gabriel sighed.

“Cara, I appreciate it, but I’m fine. I’ll be at the site in two days, and we can catch up then. I’ll even ride around with you in that death trap you call a shipwhile we wait for the flock to catch up.”

Cara’s voice was thick with concern as she answered. “It’s a date, Gabe. And no…side trips, okay? Just get here.”

Gabriel agreed and signed off. By now the heater and the atmospheric pump had his tent livable, and he unlatched his helmet, letting the pressure equalize, then removed it completely.

“You could do this outside. You have no need of a tent. You are part of Mars, but Mars is filling up.” The voice was coming from all around him, seemingly from the walls of the tent itself.

Gabriel paused, then slowly removed and inspected his vacuum suit, hanging it in the charging bay and then laying down on his bed. The problem with going insane, he thought, is that you’re the last one to know you’re doing it.

Mars is filling up. Behind him were the first wave of builders. They would trap the comet, keep it on Mars, turn the ball of ice into a giant cistern, feeding out water when needed, making sure to keep the rest of it safe until then. Behind the builders were the Pavers. They were even now building a fast, safe road from the nearest enclosure to the impact site. Once the road was complete the Plumbers would start their work, running the pipe that would carry water back to the rest of the Martian settlements. And the impact site itself would become a settlement. A small contingent of people, at first, would come to keep the pumps running and the cistern maintained. They would either bring their families or start families there, and the settlement would last long after the cistern was really needed. Other settlements would sprout out beyond the cistern. And that much more of Mars would be theirs instead of his

“Wait a moment,” Gabriel thought. “Whose side am I on? I’m just as human as they are.”

Somewhat disturbed, Gabriel willed himself to fall asleep.

The next day passed quickly, with Gabriel fully focused on finding the best possible route around craters and other new features created by the comet’s landing. Scorched and twisted boulders had been thrown in every direction. One of the scientists who had planned the whole affair was worried that the friction from the comet’s landing and the subsequent dust storms would start a global firestorm, but model after model showed that Mars’ thin and largely carbon-dioxide-based atmosphere wasn’t likely to burn. And, fortunately, it didn’t.

Gabriel kept his mind on thoughts like this to avoid the other thoughts. The ones that were telling him that he was meant to live free, that he was meant to walk under the orange sky with nothing between himself and his homeworld.

Instead he kept himself busy making up good quips for the many, many times Cara called to check in on him. She must have told a few of the others, because Gabriel’s comm link was active all day. Normally he would have been annoyed by such intrusions. Now he held to them like a lifeline.

Finally night fell and Gabriel set up his tent. After double- and triple-checking that there was a breathable atmosphere inside the tent he opened his suit and went to bed. He forced himself to breath calmly, absolutely resisted the urge to chant “mars is full” with every breath like a mantra, and finally went to sleep.

And he dreamed Mars. In his dream, for the first time, he saw Mars as a mother. Humans had named this planet after a god of war, but the planet had never seen itself that way. Mars was not a harsh, lifeless enemy. He remembered when she had life of her own, though it had never gotten larger than microscopic. He felt her misery at losing what she had, and her inability to maintain her new adopted children.

And he awoke, packed carefully, dream forgotten. He put on his vac suit, put his tent away, and started driving.

At noon Gabriel changed course, heading 45 degrees south. He turned off his comms, ignoring the frantic screams from his friends. He drove at full speed, the buggy whining about engine overheating and about unknown terrain ahead.

Twenty clicks away from where he turned he stopped the buggy and stepped out. The orange sky and the red sand merged, the world a reddish ball, like the inside of an egg as seen by the chick.

“Come to me. Mars is full. i can support you.”

And for a moment he remembered his dream. He realized he had dreamed the entire life of Mars, and that the life of a man is less than a millisecond in that time scale. Tenses, he thought, must be very hard for planets. In the moment when he stood there, his hand on the clasp holding his helmet on, he saw the future as well. It wouldn’t be too many years, less than a thousand, until man could walk free under the skies of mars. To a planet that time and this time were the same. Mars wasn’t trying to kill him, it was trying to welcome him.

Gabriel lowered his hand. He looked up into the sky. The planet he loved, the planet he called home, was calling to him. “Mars…isn’t full yet. But it will be. For now, Mars is open,” he said to the orange sky. Then Gabriel got back into his buggy, turned around and headed toward the captured comet. He turned his comms back on and explained to Cara that he wasn’t going to the desert, not now, not alone. He was bringing life to the desert, and someday perhaps their grandchildren could go to the forest instead.