Frank wandered in its light, making his way back to the city wall. The plain south of the city was littered with a truly Martian abundance of rocks, each one dogged by a long black shadow. Under the concrete arch of the city’s south gate he stopped. No one there. The gates were locked during festivals like these, to keep drunks from going out and getting hurt. But Frank had gotten the day’s emergency code out of the fire department AI that morning, and when he was sure no one was watching he tapped out the code and hurried into the lock. He put on a walker, boots, and helmet, and went through the middle and outer doors.

Outside it was intensely cold as always, and the diamond pattern of the walker’s heating element burned through his clothes. He crunched over concrete and then duricrust. Loose sand flowed east, pushed by the wind.

Grimly he looked around. Rocks everywhere. A planet sledgehammered billions of times. And meteors still falling. Someday one of the towns would take a hit. He turned and looked back. It looked like an aquarium glowing in the dusk. There would be no warning, but everything would suddenly fly apart, walls, vehicles, trees, bodies. The Aztecs had believed the world would end in one of four ways: earthquake, fire, flood, or jaguars falling from the sky. Here there would be no fire. Nor earthquake nor flood, now that he thought of it. Leaving only the jaguars.

The twilight sky was a dark pink over Pavonis Mons. To the east stretched Nicosia’s farm, a long low greenhouse running downslope from the city. From this angle one could see that the farm was larger than the town proper, and jammed with green crops. Frank clumped to one of its outer locks, and entered.

Inside the farm it was hot, a full sixty degrees warmer than outside, and fifteen degrees warmer than in the city. He had to keep his helmet on, as the farm air was tailored to the plants, heavy on CO2 and short on oxygen.