“Snail’s pace,” repeated McNally. “I like snails, right from the time I was a boy I liked them. My feel-good index has just jumped again. Tell me what you need from NASA. Maybe we could just smash a heavy spaceship into it.”
“Depends how big Nemesis is. I think we have to assume a one-kilometre asteroid, enough to take out the States comfortably. In that case you could do it with a three hundred ton spaceship. It would be a kamikaze mission, crashing into the asteroid at twenty kilometres a second.”
“Three hundred tons!” McNally exclaimed. “NASA doesn’t run to the Starship Enterprise, Willy. And we don’t have ten years, right? Say we reach Nemesis a couple of months before it’s due to hit us.”
“Then you have to shift it at a brisk walking speed.”
“What would that take?” McNally asked.
“Forget kamikaze. Hitting it with the Starship Enterprise fails by a large margin. We’d need to eject billions of tons of asteroid. For medium-strength rock or hard ice, we’d need maybe ten million tons of high explosive.”
“Or its nuclear equivalent. Ten megaton bombs surely exist. So we bury one at some optimum depth…”
“There you go again, Jim, getting your ideas from old movies. Truckloads of mining gear, diesel engines running on oxygen, engineers holding on to a spinning asteroid like the Keystone Kops. No, on any timescale likely to be available to us, burial is not a practical option. We’ll have to be guided by Judy on what a surface burst can achieve. And we still need to know what the asteroid is made of. Say it had the strength of cigarette ash? You’re back to the Saracen option.”
“So test it on the hoof. Zap it with a laser as we approach and get the composition from the spectrum of the vapour, like the Russians did with the Martian satellites. Then use an onboard computer to work out your bomb-placing strategy as you close.”
The physicist shook his head doubtfully. “Even with a nanosecond-pulse laser you’d be lucky to vaporize anything at over a hundred kilometres’ range. That gives your spacecraft maybe three seconds to analyse the spectrum of the vapour, work out the size and composition of the asteroid, calculate the optimal position for the bomb and then actually get itself into a corrected position which might be miles away. Forget it.”
Sunlight was now halfway down the crater wall and a light dew was steaming off, but down at the floor, the bowl was still in shadow and the desert air was freezing. McNally was beginning to feel a sense of oppression, as if the walls were closing in on him.
“How can we?” asked the NASA Director. “You’re telling me Nemesis might be approaching at twenty kilometres a second. We have no launch vehicles which could get out there fast and then slow down to match an approach speed like that.”
“In which case America is about to be exterminated.”
“Damn you, Willy, I have six grandchildren.”
“I’m just as fond of my dog.”
They paced on in silence. After some minutes Shafer said: “What about your big heavyweight, the Saturn Five? As I recall it could just about match the Soviets in booster power. I know you phased it out when the Shuttle came on line, but you must still have the blueprints and the launch infrastructure.”
McNally pulled the collar of his jacket up around his neck. “Sure. The blueprints are on microfilm at Marshall, and Federal Archives in East Point hold three thousand cubic feet of old Saturn documents. And sure, the old launch pads were converted for Shuttle use, but we might convert one back again with a little help from Superman. But Willy, where do we find firms to supply sixties vintage hardware? It would take so long to redesign for modern hardware and modify a pad, we’d be as well starting from scratch with a clean sheet design. You’re talking years.”
Shafer kicked thoughtfully at a stone. “By which time we’re dead.”
“Willy, there are two ways we can approach this. With an unmanned module, or a manned one.” Shafer nodded encouragement, and the NASA Chief continued: “We could build fast from an existing manned module design, or even revamp one from the Smithsonian Aerospace, and get it aloft on a Saturn/Centaur combination.”
“How long?”
McNally pondered. “The moon landings were a child’s game by comparison. The Phase A study alone would take nine months in normal circumstances. I might cut that to three or four. Acquisition planning a month, systems engineering and testing another year. Life support systems are a lot of sweat. Absolute minimum a year to launch.”
“By which time we’re dead,” Shafer repeated. They walked on. The silence in the big bowl was becoming tomblike.
“A shuttle carries people,” said Shafer. “Stuff its cargo bay with fuel. Once the astronauts are in low Earth orbit they could blast themselves into interplanetary space.”
McNally shook his head. “The Mark Three can lift eighty tons of payload into a low orbit. Even if that was pure fuel it still wouldn’t be enough. Look, Willy, ideas for boosting the lift capability of the baseline shuttle are coming out of NASA’s ears. Liquid boosters, carrier pods under the external tank, carrier pods above it, extra side-mounts etcetera. They all need more time than we’ve got.”
Shafer persisted; his voice was beginning to acquire an anxious edge: “Half a dozen shuttle launches, each time with a booster tank in the cargo hold. Fix it so the crews can take the boosters and join them on to a single shuttle like Lego. Skip the test phase”—McNally’s eyes widened with disbelief—“that way you use off-the-shelf systems all the way and all you need is a plumber.”
They were halfway round the circumference. Another lizard scurried away from them, its reptilian legs a blur of speed. McNally threw a stone after it and missed. “I’m sorry, Willy, but you’re now into fantasy.”
The familiar egg-beater sound began to echo off the crater walls as the helicopter appeared, and sank down towards them. McNally waved it away with a grand sweep of the arm, and it tilted alarmingly before veering out of sight. The sunlight had almost reached the floor of the crater.
Suddenly McNally froze. He raised a hand to silence Shafer, an unformulated thought just out of reach. Then he nodded his head, and he said, “I have a very bad idea.”
“Let’s hear it,” Shafer encouraged him.
“The Europeans have a comet soft lander. It’s called the Vesta. It could reach the asteroid.”
Shafer stopped. “That’s a bad idea?”
“The project’s well along and we’re lending them our telemetry systems. Trouble is, their Ariane Five isn’t powerful enough for a soft land.”
“Oh no,” said Shafer.
“Oh yeah. ESA are shipping Vesta to Byurkan. The Russians are launching it for them with a Proton booster.” McNally narrowed his eyes. “They’re building Vesta at Matra Astrium in Toulouse. If we could somehow get our hands on it, without arousing suspicion, we might lift it with a Saturn — Centaur combination.”
“I agree,” said Shafer excitedly. “It’s a terrible idea. A new procurement policy for NASA. Theft.”
“My career would be ruined. I might have to commit suicide,” said McNally happily, his eyes gleaming.
Shafer stopped and let McNally walk on. The NASA Chief Administrator paced slowly up and down for some minutes, muttering eccentrically to himself. He came back, his eyes narrowed. “Willy, we could bring a bomb up on a Shuttle to save payload on the Saturn. The crew would rendezvous with Vesta two hundred miles up and transfer the bomb over before the spacecraft goes hyperbolic. Goddard and JPL could handle the trajectory planning if we ever find Nemesis. Lawrence Livermore have experience with mission sensors and the bomb. I could get the Naval Research Lab to look at the overall mission design. We have our Deep Space Network…”