She kept to a pace she thought she could sustain for the whole distance. It was hard not to let loose and sprint at full speed, but no, no, that would lead to a collapse eventually. Pace yourself, she thought, gasping in short pants. Get down off the high ground into a graben so you’re out of sight. Keep oriented, are you passing south of the rover? Back up to the higher ground, for just a moment to look. There behind that low flat-topped hill, which was a small crater, with a hump on the south end of the rim— she was certain— though the rover was still out of sight, and the jumbled land was easy to get confused in. A thousand times she had gotten briefly semilost, unsure of her exact location in relation to some fixed point, usually her parked rover— not a big deal usually, as her wrist’s APS could always lead her back. As it could now too, but she was sure it was over there behind that bump of a crater.

The cold air burned in her lungs. She recalled the emergency face mask in her backpack, and stopped and yanked off the backpack and dug, pulled off the CO2 mask and put on the air mask; it contained a short supply of compressed oxygen in its frame, and with it pulled over her mouth and nose and turned on, she was suddenly stronger, faster, could hold a better pace. She ran along a strip of high ground between canyons, hoping to get a sighting of the rover round the slope of the crater apron. Ah, there it was! Panting triumphantly she sucked down the cool oxygen; it tasted lovely, but was not enough to stop her gasping. If she went down into the trough to her right it looked like it would run straight to the rover.