He looked at his bare hand, puzzled. The skin had turned a deep, uniform brown. A nuclear tan. How about that.

He snapped switches.

There was a series of sharp bangs, a shudder.

“Houston, we’ve got separation,” Jones said.

The Earth slid more rapidly past the windows, as the freed Apollo-N tumbled away from the S-NB. With separation, the tumbling seemed to ease; maybe, Priest thought, gas venting from the S-NB had been causing some of the pitching.

Jones worked at hand controllers which should have operated the RCS clusters on the Service Module. He was trying to kill the residual rates, the unwanted tumbling. “Zippo,” he said. “Still nothing, Houston; we don’t have any attitude control.”

“Acknowledged, Apollo-N,” Natalie York said. “We’re working on it. Watch out for gimbal lock.”

Priest could see the red warning disk painted on the eight-ball, drifting into the ball’s little window, the warning for incipient gimbal lock.

“Well, hell,” Jones groused, “I don’t see I can do much about that, Natalie.”

The tumble brought the discarded nuclear booster into Priest’s view. The slim black-and-white cylinder looked almost beautiful as it drifted away from him, silhouetted against the Earth’s shining skin, highlighted by sunlight. But he could see that a panel had blown out of the pressure shell surrounding the reactor core, at the base of the hydrogen tank. Inside the shell, Priest could see a tangle of pipes and Mylar insulation. And the hydrogen tank itself had been ripped open; a thin wisp of gas still vented from the tank.

Priest wondered vaguely if they ought to be focusing a TV camera on the booster.

Jones began to describe the S-NB to Houston. “There’s one whole side of the damn thing missing. I can see wires dangling, and the base of that hydrogen tank is just a mass of ripped metal. It’s really a mess…”

Now, as the S-NB rolled, Priest could see through the base of the ripped-open tank, all the way through to the NERVA reactor itself. And in there, he saw a point of light, white-hot. That’s the goddamn core. The reactor’s blown itself apart, and exposed the core. There was no sign of the biological shield, which must have been blown away. Perhaps that was what they had seen, in red-hot fragments, fountaining past the Command Module’s windows.

As he stared into the wreckage he thought he could actually feel heat on his face: heat radiating from the core itself, as if it were a tiny, captive sun.

He glanced at the radiation dosimeter number on his DSKY. Thirty thousand roentgens an hour were spewing out of the core, and through the spacecraft, in an invisible hail of gamma and neutron radiation.

Thirty thousand. It was a hard number to believe. The safe limit, according to the mission rules, was one-thousandth of a roentgen per day.

“I guess we’re kind of privileged,” Priest said. “Nobody in the history of mankind has ever gotten up so close to an exposed nuclear reaction before. The victims of the Jap bombings were killed by heat and the shock wave rather than by radiation…”

Jones cackled, and he closed his eyes. “Another first for the space program. Oh, thank you, Lord.”

Gregory Dana found it a scramble to get out of JSC. Dozens of TV, radio, and print reporters were turning up at the security blockhouse, requesting clearance and asking for access to whatever briefings NASA was planning. The parking lot opposite Building 2, the Public Affairs Office, was one of the busiest on the campus.

It was pitch-dark by the time Dana arrived at the ranch house in Lazywood Lane.

Jim and Mary lived in a pretty place. Timber Cove was a development that had sprung up in the 1960s, a couple of miles from JSC. Around the tidy, manicured streets the ranch houses were sprinkled in the greenery like huge wooden toys, individually styled, encrusted with stone cladding. The grass was rich and cool-damp, and the cultivated pine trees on the lawns were a dark green, almost black in the low lamplight.

The area was soaked with NASA connections. Once, Jim liked to boast, no less than Jim Lovell had lived next door, with his family. On happier days, Dana had come to throw baseballs with Jake, and to make paper airplanes for little Mary, and to argue the politics and engineering of spaceflight with his son…

For a few minutes Dana sat in the car. He felt as if the strength had been drawn out of him. He rolled down the window and let the cooler air waft over his face.

He could hear water lapping at the back of the house, the clink of the chain that tied up Jim’s little dinghy.

He took off his glasses and wiped them on his crumpled tie.

Later tonight Gregory was going to have to fly up to Virginia to be with Sylvia, and bring her back. He’d spoken to her on the phone several times already — the Mission Control people had given him a line — and she’d sounded calm enough. But Dana couldn’t begin to imagine how she was going to react to this.

Well, how am I reacting? Do I even understand that? My son, my only son, is in orbit right now — perhaps trapped up there — with his poor, fragile body irradiated by Marshall’s hellish abortion of a nuclear rocket. It was a situation, he thought, which the human heart simply wasn’t programmed to cope with.

And, under all his grief, he felt the dull, painful glow of anger that none of this need have been so — that it wasn’t, never had been, necessary to build nuclear rockets to get to Mars.

He pushed his glasses back on his face, shoved open the car door, and got out.

There was a Christmas wreath on Jim’s front door.

It was physically hard for him to walk up the drive, he observed, bemused. He watched his feet, his shoes of brown leather, as they lifted and settled on the gravel path, as if they belonged to some robot.

He reached the door.

He felt exhausted, as if the path had been a steep climb. It won’t be so bad, he told himself feverishly. Just ring the doorbell; that’s all you have to do. Seger had said someone from the Astronaut Office would have been there already. So you won’t have to give her the news, at least. And besides, Walter Cronkite was probably already intoning gloomy predictions on CBS.

You won’t even have to break the news. So ring the bell, damn you.

His hands hung at his sides, heavy, weak, useless.

“Apollo-N, Houston. We’re going to bring you home. Just take it easy, and we’ll bring you down. The Command Module systems are looking good at this time. You might want to dig out the medical kit—”

Natalie’s voice remained calm and controlled, and Priest, through the mounting pain in his chest and eyes, felt a surge of pride. Good for you, rookie. “I think we’ll have to pass on that,” he said. “I doubt if any of us could reach the kit, Natalie.”

“Just hang tight, Apollo-N.”

“Hey, bug-eyes,” Jones said to Priest. “I’ve got Jim’s pin in my pocket.”

“What pin?”

“His flight pin. The gold one. He’s no rookie now. I was going to give it to him after the burn. You want to reach over? He might like to see it.”

“Maybe later, Chuck. I think he’s sleeping.”

“Sure. Maybe later.”

Donnelly, listening to the clamor of voices on the loops, felt numb, unreal, as if all that radiation had gone sleeting through his own body.

The reentry was going to be a mess. The systems guys were hurrying through an improvised checklist, designed to get the Command Module configured to bring itself home. At the same time, the trajectory guys were figuring out where they could bring the bird down; it had to be near enough to a Navy vessel that could effect an emergency recovery and offer medical facilities…