northeast at best. In their attempts to fly across the wind the poor Arrowhead was bouncing like a hang glider, yanking them up and down, up and down, up and down, as if the gondola were indeed attached to the underside of a trampoline. But despite all that, they still weren’t going in the direction they wanted to go.
Darkness fell again. They were carried farther northeast. On this heading, they were going to miss Underhill by several hundred kilometers. After that, nothing; no settlements at all, no refuge. They would be blown over Acidalia, up onto Vastitas Borealis, up to the empty petrified sea of black dunes. And they did not have enough food and water to circumnavigate the planet again and give it another try.
Feeling dust in her mouth and eyes, Nadia went back to the kitchen and heated them a meal. Already she was exhausted, and, she realized as the smell of food filled the air, extremely hungry. Thirsty, too, and the water recycler ran on hydrazine.
Thinking about water, an image came to her mind, from the trip to the north pole: that broken permafrost gallery, with its white spill of water ice. Now how was that relevant?
She worked her way back up to the cockpit, holding onto a wall with every step. She ate a dusty meal with Arkady, trying to figure it out. Arkady watched their radar screen, saying nothing, but he was looking concerned.
Ah. “Look,” she said, “if we could pick up the signals from the transponders on our road to Chasma Borealis, we could come down and land by it. Then one of the robot rovers could be sent up to get us. The storm won’t matter to the robot rovers, they don’t go by sight anyway. We could leave the Arrowhead tethered, and drive back home.”
Arkady looked at her, finished swallowing. “Good idea,” he said.
But only if they could actually pick up the road’s transponder signals. Arkady flicked on the radio and called Underhill. The connection crackled in a storm of static almost as dense as the dust, but they could still make themselves understood. All through that night they conferred with the crowd back home, discussing frequencies, band-widths, the power of the dust to mask the transponder’s fairly weak signals, and so on. Because the transponders were designed only to signal rovers that were nearby and on the ground, it was going to be a problem hearing them. Underhill might be able to pinpoint their location well enough to tell them when to descend, and their own radar map would give them a general fix on the road’s location as well; but neither of these methods would be very exact, and it would be almost impossible to find the road in the storm if they didn’t land right on it. Ten kilometers either way and it would be over the horizon, and they would be out of luck. It would be a lot more certain if they could just latch onto one of the transponder signals, and follow it down.
In any case, Underhill dispatched a robot rover on the road north. It would arrive in the area of the road they were expected to cross in about five days; at their current speed they would cross the road themselves in about four days.
When the arrangements were finished, they traded watches through the rest of the night. Nadia slept uneasily on her off watches, and spent much of the time lying on the bed feeling the wind bounce her. The windows were as dark as if curtains had been drawn. The roar of the wind was like a gas stove, and then occasionally like banshees; once she dreamed they were inside a great furnace full of flame demons, and woke sweating, and went forward to relieve Arkady. The whole gondola smelled of sweat and dust and burnt hydrazine. Despite all the gaskets’ micron seals, there was a visible whitish film on all the surfaces inside the gondola. She wiped her fingers across a pale blue plastic bulkhead, and stared at her fingers’ mark. Incredible.
They bounded along through the gloom of the days, through the starless black of the nights. The radar showed what they thought was Fesenkov Crater, running under them; they were being carried northeast still, and there was absolutely no chance they would be able to buck the storm and get south to Underhill. The polar road was their only hope. Nadia occupied her off watches by looking for things to