It was night, and Sax went outside. Wandering in the darkness, under the immense cliff of the Great Escarpment, in the region just north of where Kasei Vallis broke through the wall. Sei meant star in Japanese, ka fire. Fire star. It was the same in Chinese, in which huo was the syllable the Japanese pronounced as ka, and hsing, sei. A Chinese word to start with, Huo Hsing: fire star, burning in the sky. They said Ka was what the little red men called it. We live on fire. Sax was distributing seeds in the ground, the hard little nuts pushed just under the surface of the sand flooring the chasm. Johnny Fireseed. There in the southern sky Deimos burned, slowly losing way through the stars, rolling westward at its own slow pace. Now pushed by the pinpoint comet burst on its eastern edge. The elevator rising over Tharsis was invisible, the new Clarke perhaps one of the dimmer stars in the southwest sky, it was impossible to say. He kicked a rock by accident, bent down and planted another seed. After the seeds were all out, there were starter packets of a new lichen to distribute. A chasmoendolithic strain, very hardy, very fast to propagate, very quick to pump out oxygen. Very high surface-to-volume ratio. Very dry.

A bip on the wrist. He switched the voice into his helmet intercom as he continued to take the little nuts out of his thigh pocket and shove them into the sand, careful to avoid damaging the roots of any of the sedges or other ground cover that dotted the ground like furry black rocks.

It was Peter, sounding excited. “Sax, Deimos is coming up on them now, and the AI seems to have acknowledged that it’s not in its usual spot in its orbit. It’s been mulling it over, they say. The attitude jets all through their sector have started a bit early, so we’re hopeful that the system is responding.”

“Can’t you calculate the oscillation?”

“Yes, but the AI is proving recalcitrant. It’s a stubborn bastard, the security programs are pretty watertight. We can just figure out enough from independent calculations to see that it’s going to be a pretty close pass.”