Flying over Noctis Labyrinthus! The wind keened over the blimp’s taut transparent material, and they bounced unpredictably up and down on the wind, while also rotating horizontally in what seemed an uncontrolled spin; but then Monica laughed and began manipulating the controls before her, and quickly they were proceeding south across the labyrinth, over canyon after canyon making their irregular X intersections. Then over the Compton Chaos, and the torn land of the Illyrian Gate, where it dropped into the upper end of the Marineris Glacier.

“These things’ jets are much more powerful than they need to be,” Monica told him through their headphones. “You can make headway into the wind until it reaches something like two hundred and fifty kilometers an hour, although you wouldn’t want to try that. You also use the jets to counteract the blimp’s loft, to get us back down. Here, try it. That’s left jet throttle, that’s right, and here are the stabilizers. The jets are dead easy, it’s using the stabilizer that needs some practicing.”

In front of Nirgal was a complete second set of controls. He put his hands on the jet throttles, gave them pushes. The blimp veered right, then left. “Wow.”

“It’s fly by wire, so if you tell it to do something disastrous, it’ll just cut out.”

“How many hours flying time do you need to learn this?”

“You’re doing it already, right?” She laughed. “No, it takes a hundred hours or so. Depends on what you mean by knowing how to do it. There’s the death mesa between a hundred hours and a thousand hours, after people have relaxed and before they’re really good, so that they get into trouble. But that’s mostly hang gliders anyway. With these, the simulators are just like the real thing, so you can put in your hours on those, and then when you’re actually up here you’ll have it wired even though you haven’t officially reached the flying time limit.”

“Interesting!”

And it was. The intersecting sapped canyons of Noctis Labyrinthus, lying under them like an enormous maze; the sudden lifts and drops as the winds tossed them; the loud keening of the wind over their partially enclosed gondola seats. . . . “It’s like becoming a bird!”

“Exactly.”

And some part of him saw it was going to be all right. The heart is pleased by one thing after another.

• • •