Under the guidance of PGNS Challenger was heading for a point a couple of miles beyond the big escarpment, north of the mouth of the major outflow valley, just as planned. But when he saw it close up he could see the land was uneven, scoured out, ribbed with what looked like gravel bars. And there was an impact crater, low, eroded, right in the middle of it all, with a teardrop-shaped island of debris behind that.

“Scablands,” he said. “Natalie, you’re going to love it. Because it looks like you were right. It looks like a fucking river bottom out there…”

But he couldn’t put the MEM down in that shit.

Solenoids rattled, and Challenger shuddered. The computer was revising its trajectory all the time, as information came in from the radar. Gershon was surprised how often the attitude jets were firing, though; it was much more frequent than in the sims.

Stone was still calling out height and velocity readings. “Seven hundred feet, down at thirty-one feet per second. Six hundred. Down at twenty-nine. Five hundred forty feet. Down at twenty-five.”

Decision time, Ralph.

He flicked a switch to override PGNS.

He pressed the translation controller, and toggled the little thruster switch to slow the MEM’s fall. Challenger responded smartly to his touch, with a rattle of solenoids.

Suddenly, he was piloting the ship. The response was crisp and sharp. The thrusters banged, and the MEM pitched forward. He found himself leaning into his restraints.

Challenger drifted over the surface of Mars, under his command.

He was aware of Stone’s eyes on him.

“Low gate,” Stone said. “Five hundred feet. Thirty-five degrees pitch. Coming down at twenty-one feet per second.”

The MEM was still falling, but it was skimming forward, sliding over the broken, flooded-out terrain. I’ve got to get north. Away from this shit from out of the old terrain. North; that’s the place to be. On the smooth lava plains beyond the flooding.

Test pilots had an adage. When in doubt, land long. Ralph Gershon kept on going, looking for a place where he could land long.

“Four hundred feet, down at nine feet per second. Three hundred fifty feet, down at four. Three hundred thirty… Watch your fuel, Ralph.”

Watch your fuel. Sure. The mission planners had sent him all this way, looping around the sun, to make landfall on an alien planet for the first time, and they’d given him about two minutes’ worth of hovering fuel to do it.

But this is what you wanted, Ralph. Isn’t it? This is what it’s all been about, all these years. To be able to fly to a planetfall, just like Armstrong.

He felt his heartbeat pumping up.