Challenger slid down U.S. Highway One, braking easily.
“AGS and PGNS agree closely,” Stone said. Stone was acting as the navigator; he was telling Gershon that the redundant-pair primary and abort guidance systems were agreeing with each other. “We’re looking good at three, coming up… Three minutes. Altitude thirty-nine thou five.” That height reading was still only an estimate from the two guidance computers, though; the landing radar had still not acquired its lock. And Stone would also be able to read off heights from the altimeter, although that instrument, working on the pressure of the unfamiliar Martian atmosphere, was experimental, and its data excluded by the mission rules.
“Still go,” Stone said. “Take it all at four minutes… We’re go to continue at four minutes.”
“Rager,” Gershon said tersely.
“The data is good. Thirty-three thou…”
But caution and warning lights were glowing on Gershon’s station. The landing radar should have been working by now; it should have locked onto its own signals bouncing off the ground.
But it hadn’t achieved lock.
“Where’s that goddamn radar, Ralph?” Stone asked.
“Punch it through again.”
“Yeah.” Stone tried.
“Come on, baby,” Gershon said quietly. “Let’s have the lock on.” But there was no change. “Come on.”
“Does talking to it do any good?” York asked drily.
“Shut up, Natalie,” Stone said, distracted.
Gershon felt a stab of fury. Other data was still good. Velocity looked fine, and the altitude estimates from both AGS and PGNS were in agreement. But without the radar — and even if the altimeter worked — he was screwed. The mission rules said, No radar lock by ten thousand feet and you abort.
Stone said, “Try cycling the landing radar breaker.”
Gershon pulled out the radar’s circuit breaker, his muscles tense with anger, and shoved it back in its slot. “Okay, it’s cycled.”
The caution lights continued to show. No lock.
He turned to look Stone in the eye. “Fine day for a landing.”
He meant: Fuck the rules. Fuck the radar. Fuck Houston; they’re so far away we’ll be on the surface by the time they know what’s going down. We’ve come too far to quit now. I say we go for a landing, by eye if we have to. Fuck it.
Stone stared back at him.
Damn it, you cold bastard. What are you going to do?
Gershon could feel the cabin tip up around him; beyond his big window, sky and a fine edge of red landscape slid past. Challenger was beginning to pitch up, as it dropped closer to the ground.
“Twenty-four thousand feet,” Stone said. “Coming up to throttle down. Mark.”
The primary guidance program would take the descent engine down to 60 percent thrust. Gershon could feel the thin vibration subsiding smoothly. Right on schedule. “That felt good,” he said. “Better than the sims.”
“Twenty-one thousand. We’re still go. Apart from the radar lock. Velocity down to twelve hundred feet per second.”
Twelve hundred. Aircraft speed. Gershon took hold of his controls. I’m flying in the atmosphere of Mars. He looked out of his window. The stars were all washed-out, and the sky was a tall dome of brown light. And he could see the ground. It was a rumpled landscape that slid underneath him. Visibility was good: the contrast, the shadows cast by the low morning sun, made everything stand out.
Challenger was approaching the landing site in a broad sweep from the southwest, so it was flying over the ancient, cratered terrain of the southern hemisphere. It was almost like a lunar landing sim, with craters piled on craters, some so old and huge they were almost obliterated by newer strikes. But these craters had sand dunes rippling across their floors, and there was one big old fellow whose walls looked like they had collapsed under a stream of running water. The Moon, it ain’t.
The landscape was desolate, curving tightly, forbidding. It was an empty planet, no ground support… No runway lights down there, boy. On the other hand, nobody shooting at your ass, either.
“Seven minutes thirty,” Stone said. “Sixteen and a half thou. Coming up on high gate. Still no lock.”
“High gate” was the point in the trajectory where Gershon should be able to see his landing site for the first time. He peered ahead.
The designated landing site was just to the north of an escarpment at the mouth of an outflow valley. The valley, according to York’s descriptions, would look like a dry riverbed. Gershon had studied the site from orbiter photographs and plaster-of-paris models until he knew it like he knew his own apartment.
But coming in now, with the sun low, and the ship still tipped up at more than fifty degrees, and the light glinting off his little triangle of a porthole…
Nothing looked like it was supposed to. The land was complex, tortured, its nature changing rapidly. Every shadow was deep and black, and the ocher-colored surface features seemed to leap out toward him, the vertical scale magnified by the contrast.
“Fifteen thousand,” Stone said. “Still no lock.”
Shit.
“Okay, Ralph, let’s go over the abort procedure.” Stone sounded resigned.
Goddamn it to hell, he’s given up.
“We pitch over, activate the ascent program… countdown to mission abort starts at eight thousand feet—”
“No. Don’t abort,” Natalie York said suddenly.
Stone looked at her. “Huh?”
“Don’t abort. We may be flying over a radar-dark area.”
“And what,” asked Stone drily, “is a radar-dark area?”
“Volcanic ash,” she said. “Pumice.” She was straining in her harness, trying to see the battered landscape out of their pilots’ windows. “Low-density stuff; not many rocks. It reflects radar badly. There’s nothing for the landing radar to lock on to.”
“Or maybe,” Stone said, “the landing radar is screwed.”
“Don’t abort.”
Stone and Gershon exchanged looks.
“Nine thousand,” Stone said. “Still no lock.”
They’d already busted the mission rules, Gershon realized.
Stone said, “Ralph—”
And then the warning lights went out. The radar lock had come in.
York gasped, an explosion of relief.
“Jesus.” Gershon slammed his fist into his control station. “We is fucking go.”
“We is indeed,” Stone said tightly.
Gershon twisted over his shoulder to look at York. “I guess we flew right on over all that pumice stone, huh.”
She stared back at him. “I guess.”
He had no idea if she’d just been bullshitting, he realized, about the pumice stone. He didn’t think York was the type to do that, but it was possible. And he also didn’t know if Stone would really have pulled the plug, or let him go on and try to land without the radar.
He didn’t, he realized, know his crewmates as well as he thought he did.
“Eight thousand,” Stone rattled off. “Down velocity one hundred feet per second. We’re go for the landing.”
“Rager.”
Gershon took hold of his controls. He had an attitude control adjuster in his right hand — a joystick with a bright red pistol grip — and on his left there was a toggle switch called the thrust translator controller, which would squirt the down-pointing reaction thrusters to reduce the rate of fall. It was all linked up by the electronics to the reaction control subsystem, which would do most of the steering for him.
He pulsed the reaction control thrusters; solenoids rattled comfortingly.
He handed control back to the computer. “Manual auto attitude control is good.” He felt a surge of renewed confidence. The radar was locked in, and the thrusters were copacetic. When the time came, when he had to take control of the ship for the final landing, he knew that everything would be fine.