“There’s Ascraeus Mons,” Arkady said, pointing at the radar screen. “Good image.” He laughed. “Best view of it we’re going to get this time around, I’m afraid. Too bad, I was really looking forward to seeing them! Remember Elysium?”
“Yeah yeah,” Nadia said, busy running simulations of the batteries’ efficiency. Daily sunlight was near its perihelion peak, which was why the storm had started in the first place; and the instruments said that about 20 percent of full daylight was penetrating to this level (it felt to her eye more like 30 or 40); therefore it might be possible to run the props half the time, which would help tremendously. Without them they were losing altitude although that might just be the ground rising under them. With the props they might be able to hold a steady altitude, and influence their course by a degree or two.
“How thick is this dust, do you think?”
“How thick?”
“You know, grams per cubic meter. Try to get Ann or Hiroko on the radio and find out, will you?”
She went back to see what they had on board that could be used to power the props. Hydrazine, for the bomb-bay vacuum pumps; the pump motors could be wired to the props, probably. Then there were spare solar panels, and the solar panels in the emergency kit. If she could get them outside she could run whatever extra insolation they caught into the prop batteries. Also, in a sandstorm like this there was light coming from all directions, so some should probably be pointed down. As she rooted through the equipment locker looking for wire and transformer sand tools she told Arkady the idea, and he laughed his madman laugh. “Good idea, Nadia! Great idea.”
“If it works.” She rummaged through the tool kit, sadly smaller than her usual supply. The light in the gondola was eerie, a dim yellow glow flickering with every gust. The view out the side windows shifted from pockets of complete clarity, with thick yellow clouds like thunderheads sailing north with them, to complete obscurity, all the window surfaces streaming with dust that wormed and spun like a particularly unpleasant screensaver. Even at twelve millibars the blast of the wind was tossing the dirigible about; up in the cockpit Arkady was cursing the autopilot’s insufficiency. “Reprogram it,” Nadia called forward, and then remembered all his sadistic simulations on the Ares, and laughed out loud: “Problem run! Problem run!” She laughed again at his shouted curses, and went back to work. Arkady yelled back information from Ann. The dust was extremely fine, average particle size about 2.5 microns; total column mass about 1-3 grams per cm-2, pretty evenly distributed from top to bottom of the column. That wasn’t so bad; drop it on the ground and it would be a really thin layer, which was consistent with what they had seen on the oldest freight drops at Underhill.
When she had prepped all the solar panels she banged down the passageway to the cockpit. “Ann says the winds will be slowest close to the ground,” Arkady said.
“Good. We need to land to get the panels outside.”
So that afternoon they descended blind, and let the anchor drag until it hooked and held. The wind here was slower, but even so Nadia’s descent in the sling was harrowing. Down and down into rushing clouds of yellow dust, swinging back and forth . . . and there it was right under her boots, the ground! She hit and dragged to a halt. Once out of the sling she found herself leaning into the wind; thin as it was it still struck like blows, and her old feeling of hollowness was extreme. Visibility billowed back and forth in waves, and the dust flew past so fast it was disorienting— on Earth a wind that fast would simply pick you up and throw you, like a broom-straw in a tornado.
But here you could hold your ground, if only just. Arkady had been slowly winching the dirigible down on the anchor line, and now it bulked over her like a green roof. It was weirdly dark underneath it. She unreeled the wires out to the wingtip turboprops, taped them to the dirigible and crimped them to the contacts inside, working fast to try to reduce their exposure to dust, and to get out from under the Arrowhead, which was bouncing on the wind. With difficulty she drilled holes in the bottom of the gondola fuselage, and attached ten solar panels with screws. As she was taping the wiring from these to the plastic fuselage, the whole dirigible dropped so fast that she had to collapse onto her face, her whole body spread-eagled on the cold ground, the drill a hard lump under her stomach. “Shit!” she shouted. “What’s wrong?” Arkady cried over the intercom. “Nothing,” she said, jumping up and taping faster than ever. “Fucking thing— it’s like working on a trampoline—” Then as she was finishing the wind picked up strength yet again, and she had to crawl back down to the bomb bay, her breath rasping in and out of her.