She felt cold; she put her fork down. “But those guys only had spaceflight records of two, three weeks—”

“Yeah. But we’ve spent four billion years adapting to life on Earth. For a while we thought spaceflight was easy. I guess we really do put our lives on the line, right? But then, some people seem to adapt well. They come home with trivial amounts of muscle atrophy, for instance. Maybe you’ll be lucky, Natalie. Maybe you’ll be an immune…”

“Well, if we were in a rational world,” York said, “we wouldn’t have a mission profile like Ares anyhow. The Ares plan is really a relic of the sixties.”

“Yeah. When the emphasis was just on getting there, not on what you do when you get there. If we were smart, we wouldn’t plan for a thirty-day stopover; we’d look to put you up there for a year. On the Martian surface you’d be relatively protected. On your brief little trip you’ll soak up almost as many REMs as on a Hohmann mission twice the duration, which would earn you five hundred days on Mars. On this one mission, you’ll come close to your legal lifetime dosage.”

“According to OSHA guidelines, right?”

“Yeah. Anyhow,” he went on, “a long stopover on Mars would probably be better for you anyway, to give you time to recover from the effects of the long zero-G transit…

“Ah, hell.” He pecked at his food. “You know, you could say we’re not ready to do this, yet. We’ve been studying Mars mission options for thirty years. Right back to von Braun. And the basic problems — the energy needed to get out of Earth’s gravity well, to cross interplanetary space — none of that has changed. And we haven’t come up with any fundamentally smarter solutions than von Braun’s, either. We’re still firing off big hydrogen-oxygen rockets, because we don’t see what else we can do.”

She felt pleased, to hear someone like Bleeker talk like this. Maybe the culture was changing, slowly. But he might have been discussing baseball scores for all the inflection in his voice.

“I can never read you, Adam,” she said frankly. “You know, I’ve often thought the same thing. That we’re not ready to go yet…”

He nodded, smiling faintly. “I figured.”

“But it won’t stop me going, anyhow.”

“No. And it wouldn’t stop me, if they’d let me.”

“You’re not trying to talk me out of it?” She tried to inject some humor into her voice, but wasn’t sure how successful she was.

“I would if I thought I could,” he said seriously. “Not that it would do me any good.” He shook his head. “You know what was the hardest thing?” he asked suddenly.

“What?”