Stephen Baxter: Ark

“Ten to power twenty-nine kilograms,” Venus Jenning called out. She was a black girl whose family had come from Utah, fleeing the gathering Mormon uprising. As far as Holle could tell she’d figured that number out in her head. Even while she worked, she was reading a yellowing paperback book under her desk, a gaudy science fiction title.

“Give me that in English,” Liu snapped back. “What does that number mean?”

Kelly said, “One-tenth the mass of the sun. You’d have to convert one-tenth of all the sun’s mass to energy to be able to build a warp bubble of that size.”

“Not exactly practical,” Liu said. “And that remains our fundamental problem, after years of studying this concept. We just don’t have the energy resources to build a warp bubble of the size we need.” He drew a big red cross through the equations and diagrams on the board.

Again Holle found herself thinking out loud. “If the answer’s not the one you want, maybe you’re asking the wrong question.”

Liu turned to her again.

“I’m sorry,” she said. “It’s something my dad always says.”

“Then what is the right question?”

Zane said quietly, “Maybe, how big a warp bubble can we create?”

Liu thought that over. “OK. Let’s run with that. What’s the most energetic event humans can control?”

“Nuclear bombs,” Thomas Windrup called. “Thermonuclear actually.”

“Right,” Liu said. “And the biggest blast of all was?”

That sent them scrambling to their computers, and whispering into search engines.

It was Susan Frasier who came up with the answer. “30th October 1961. A Russian test. Fifty-seven megatons, detonated at Novaya Zemlya.” She smiled, always friendly, always eager to please.

“All right. And if that mass-energy was applied to creating a black hole?”

It took them a minute to find out how to convert energy measured in an equivalent tonnage of TNT into joules. This time Kelly made sure she was the first to come up with the final answer. “Its radius would be ten to minus twenty-seven meters.”

Liu said, “Give me that-”

“In English,” Don said. “Well, it’s eight orders of magnitude above the Planck length, the smallest possible. But it’s only one-thousandth of the radius of a one-mega-electron-volt neutrino! You couldn’t even fit a neutrino in there, let alone a spaceship!”

There was a ripple of laughter, and Zane blushed.

But Liu just stood in silence, his eyes working as if chasing an elusive thought. “Class dismissed.” Abruptly he walked out.

Grumbling, the students started packing away their stuff. Don said to Holle, “Now see what you’ve done. Liu’s like that when he gets an idea. You better hope it’s a good one or he’ll rip your head off for wasting his time. Come on. I’ll show you where to buy a soda.”

Holle was relieved to get home that night, to the apartment her father had rented in the same block as the Tattered Cover Book Store, a secondhand store that was still one of Denver’s most thriving businesses as nobody was printing new books any more. She dumped her bag in the hall, fetched a glass of water and made her way to the big living room, where the wall-mounted TV was showing updates on the Rocky Mountain News channel.

Patrick didn’t hear her come in. He was sitting on the floor, his back against the sofa, one arm over a cushion and the other hand cradling a glass of corn liquor. He had his shirt open at the neck, his shoes off, his black-socked feet crossed.

The news was uniformly awful, Holle saw as she glanced at the big multiscreen. In Denver the police were shaping up for another night of trouble from the itinerant agricultural workers in the City Park. Elsewhere diplomatic notes were being exchanged with Utah; Mormon leaders in Salt Lake City were now refusing to pay federal taxes. President Vasquez was going to make a statement about that. Seawater forcing its way up the Tennessee valley from Alabama was causing yet another evacuation crisis, producing yet more images of sodden, huddled people tramping along rain-spattered highways. The government was considering sending troops into the Friedmanburgs, the troubled new cities on the Great Plains, where residents were protesting against exploitation by the rich who had bought up the land and funded much of the development in the first place. Holle knew her dad had something to do with that. Surviving recon satellites reported what appeared to be nuclear detonations going off in Tibet, the flashpoint of friction between India, China and Russia.

Meanwhile there were more tsunamis and earthquakes and volcanoes as the Earth shuddered under the weight of the water that laid ever more heavily over the continents. These were reported against a summary map that showed that some forty percent of the world’s pre-flood land area had been lost, some four billion people displaced.

Holle hated the news. All these shells of horror and misery and conflict, spreading out around the bubble of safety Holle had grown up in-which, she was coming to realize, was a very special place. And though sometimes there would be scientists talking about how the flood might be ending soon, the water receding, they never seemed to have much to go on, and her father never responded to the faint hopes they raised.

“Dad, can’t we switch over to Friends?”

Patrick jumped. He hadn’t known Holle was there. “Oh, hi, sweets.” He snapped the TV over to a multiscreen conference call; Holle recognized Edward Kenzie, a suntanned Nathan Lammockson, and others. Their deep voices rumbled. He lifted his arm, making room for her. She got down on the carpet next to him and huddled in. He was hot, tired, sweating. His smell was immensely reassuring. “Sorry,” he said, “I guess I was playing hooky. I’m supposed to be in this conference. Friends later, maybe. Well, it’s on all day and all night.”

Holle had grown up with the old pre-flood TV shows. They were comforting, set in a world as unreal to her as any fairy tale. “What’s the conference about?”

“An astronomical survey going on at an observatory in Chile. Place called La Silla, very high up. It’s South America, you know? Used to be owned by the Europeans, but now Nathan Lammockson, who’s based in Peru, is supporting it for us. Not that he knows what we’re doing up there specifically.”

“Looking for planets, I bet.”

“Well, that’s the idea. Somewhere for the Ark to go. And once the new space center is up and running, there’s a plan to run a starshade mission.”

“A what?”

“I’m not sure I understand it, but it’s interesting. You send up a giant sheet, spinning for stability. It looks like a flower, with petals. Then you have a conventional telescope-we’re using the Hubble-thousands of kilometers away. The shade is supposed to block out the light of the star, allowing the telescope to see any planets. With that arrangement we should be able to image continents on an Earthlike planet, even out to thirty or forty light-years. It’s a scheme that was championed years ago by an astronomer at the University of Colorado at Boulder, which is how we were able to dig it up.”

“And this is your idea of taking a break, watching the news? It’s always bad.”

“I know.”

“Everybody’s frightened, I think sometimes.” It was true: people were frightened of the flood, which was still remote from this place, and frightened of the waves of eye-dees for the dirt and disease and hunger they brought and the space they used up, and people were frightened of each other, for in the future there mightn’t be room for everybody. Holle herself would have felt a lot safer if Alice Sylvan, who she’d grown up thinking of as a kind of honorary aunt, hadn’t got herself taken out by a sniper in downtown.