Dan felt his jaw drop open. Without the shield they’d be cooked by the next solar radiation storm.

“We’ve gotta get back to Selene pronto,” Pancho said. “Before another flare breaks out.”

“What’re our chances?” Dan asked, his throat dry.

She waggled a hand. “Fifty-fifty… if we’re lucky.”

We won’t have to go outside, will we?” Cardenas asked nervously. She was following George through the maze of pumps and generators up on the topmost level of Selene. Color-coded pipes and electrical conduits lined the ceiling; Cardenas wondered how anyone could keep track of which was which. The air hummed with the subdued sounds of electrical equipment and hydraulic machinery. On the other side of the ceiling, she knew, was the grassy expanse of the Grand Plaza — or the bare dusty regolith of the Moon’s airless surface. “Outside?” George echoed. “Naw, there’s a shaft connectin’ the tempo to the tunnel… if I can find th’ fookin’ tunn — ah, there it is!”

He pulled a small hatch open and stepped over its coaming, then reached a hand back to help Cardenas. The tunnel was dark, lit only by the hand-torch George carried. Cardenas expected to see the evil red eyes of rats in the darkness, or hear the slithering of roaches. Nothing. Selene is clean of vermin, she thought. Even the farmlands have to be pollinated artificially because there aren’t any insects here. Not yet, she thought. Sooner or later, though. Once we start allowing larger numbers of people up here, they’ll bring their filth and their pests with them. “Here we are,” George said.

In the circle of light cast by his torch, she saw the metal rungs of a ladder leading up along the wall of the tunnel.

“How much farther does the tunnel go?” she asked in a whisper, even though she knew there was no one else there.

“Another klick or so,” George answered. “Yamagata people wanted to drill all the way through the ringwall and out to Mare Nubium. Got too expensive. The cable car over the top was cheaper.”

He scampered up the ladder, light and lithe despite his size. Cardenas started to follow him.

“Wait a bit,” George called down to her. “Got to get this hatch unstuck.”

She heard metal groan. Then George said, “Okay, up with you, now.” The ladder ended in an enclosed area about the size of her apartment unit down inside Selene. It was a cylindrical shape, like a spacecraft module. “We’re on the surface?” Cardenas asked, trying to keep her voice from shaking. “Buried under a meter of dirt from the regolith,” George said happily. “Safe as in church.”

“But we’re outside.”

“On the slope of the ringwall. Just below the cable-line. The original idea was, if there’s an emergency with the cable-trolley, people could stay in here till help arrives.”

She looked around the shelter warily. A pair of double-decker bunks stood at the far end, the hatch of an airlock at the other. Inbetween was a small galley with a freezer, microwave oven, and sink; some other equipment she didn’t recognize; two padded chairs; a desk with a computer atop it and a smaller chair in front of it…

And a big metal cylinder sitting in the middle of the floor, crowding the alreadycramped quarters. One end of the cylinder was attached to a large pair of tanks and a miniaturized cryostat.

“Is that a dewar?” Cardenas asked.

George nodded. “Had to hide the woman inside it from Humphries.”

“She’s dead?”

“Preserved cryonically,” George said. “There’s hopes of reviving her.”

“She won’t be much company.”

“’Fraid not. But I’ll pop back here every few days, see that you’re okay.” Stepping toward the desk, trying to hide her anxiety, Cardenas asked, “How long will I have to stay here?”

“Dunno. I’ll have a chat with Dan, see what we should do.”

“Call Doug Stavenger,” she said. “He’ll protect me.”

“I thought you didn’t want to put him in the middle of this scrape.” She wrapped her arms around herself, trembling with cold fear. “That’s before I knew you were going to put me out here.”

“Hey, this isn’t so bad,” George said, trying to sound reassuring. “I useta live in tempos like this for months at a time.”

“You did?”

“Yup. Me and my mates. This is like home-sweet-home to me.”

She looked around the place again. It seemed smaller than her first view of it. Closing in on her. Nothing between her and the deadly vacuum outside except the thin metal of the shelter’s cylinder and a heaping of dirt over it. And a corpse in the middle of the floor, taking up most of the room.

“Call Stavenger,” she pleaded. “I don’t want to stay here any longer than I have to.”

“Sure,” said George. “Lemme talk to Dan first.”

“Make it quick.”

“The magnetic shield is going to blow up?” Dan asked, for the thirtieth time. Pancho sat across the table from him in Starpower 1’s wardroom. Amanda was on the bridge as the ship raced at top acceleration back toward Selene. Fuchs was in the sensor bay, assaying the samples he’d chipped from Bonanza. “You know how superconductors work,” Pancho said, grimly. “They have to stay cooled down below their critical temperature. If they go above that temperature all the energy in the coil gets dumped into the hot spot.”

“It’ll explode,” Dan muttered.

“Like a bomb. Lots of energy in the superconductor, boss. It’s a dangerous situation.”

“There’s more than one hot spot?”

“Four of ’em so far. Wouldn’t be surprised if more of ’em crop up. Whoever bugged this ship didn’t want us to get back home.”

Dan drummed his fingers on the table top. “I can’t believe Kris Cardenas would do this to me.”

“It’s Humphries, pure and simple,” said Pancho. “He could kill you with a smile, any day.”

“But he’d need Kris to do this.”

“Look,” Pancho said, hunching forward in her chair. “Doesn’t matter who spit in whose eye. We got troubles and we’ve gotta figger out how to save our necks before that magnetic coil goes up like a bomb.”

Dan had never seen her look so earnest. “Okay, right. What do you recommend?”

“We shut down the magnetic field.”

“Shut it down? But then we’d have no radiation shield.”

“Don’t need it unless there’s a flare, and we can prob’ly get back to Selene before the Sun burps another one out.”

“Probably,” Dan growled.

“That’s the chance we take. I like those odds better’n letting the coil’s hot spots build up to an explosion that’d rupture the ship’s skin.”

“Yeah, you’re right,” Dan said, reluctantly.

“Okay, then.” Pancho got up from the table. “I’m gonna shut it down now.”

“Wait a minute,” said Dan, reaching for her wrist. “What about the MHD channel?”

Pancho shrugged. “No problems so far. Prob’ly hasn’t been bugged.”

“If it goes, we’re dead, right?”

“Well…” She drew the word out. “We could dump the coil’s energy in a controlled shutdown. That wouldn’t affect the thrusters.”

“But we’d lose our electrical power.”

“We could run on the fuel cells and batteries — for a while.”

“Long enough?”

Pancho laughed and headed for the hatch. “Long as they last, boss,” she said over her shoulder.

“Murphy’s Law,” Dan growled after her.

If anything can go wrong, it will: that was Murphy’s Law. Now I can add Randolph’s corollary to it, he thought: If you turn off your radiation shield, you’re certain to be hit by a solar flare.