“Hunters?” Leclerc wondered, gasping for breath.
“The survivalists,” Webb suggested. “How far have we come?”
“We must have dropped a couple of thousand feet.” Suddenly, even after their exertions, the woods seemed chilly.
“Maybe we should cut off to the left and find the road,” Judy proposed.
“Let’s take five minutes,” Webb said, glancing in alarm at Leclerc’s beetroot face. They sat down on the pine needle carpet and, joy of joys, Judy produced a large bar of chocolate. The gunfire had stopped. They munched quietly for a while, a little uneasy. Leclerc got up and strolled in the direction the gunfire had been. He vanished into the gloom of the woods.
A couple of minutes later Whaler and Webb were relieved to see him strolling back.
“See anything?” Webb asked.
Leclerc gave a Gallic shrug before flopping down again. “I am not sure. Perhaps some animal.”
“Let’s get out of here,” Judy suggested.
They stood up. The Frenchman glanced nervously back in the direction he had come. “We are lost, yes?”
“Somebody knows where we are,” Judy said looking into the trees on the route they had just come down. A man of about twenty, wearing khaki and green battledress and carrying a long-barrelled rifle with a telescopic sight, emerged from the shadows. A country boy, overweight but with an abnormally thin face smeared with black. The dark eyes in the face were set close together. Webb recognized the eyes as he approached. They were xenophobic eyes, intolerant eyes; they were eyes filled with ignorance and suspicion and the superstition of centuries.
“Mo’nin’. You folks from the Fed’ral Gov’ment?” Spoken through tight, disapproving lips.
“No, we’re just visiting,” Webb said, slipping into an exaggerated Oxford accent. Leclerc would lay on the Parisian and Judy would keep her mouth shut.
“But y’all from up top, right?”
“The observatory, yes.”
The man contemplated that, his close-set eyes flickering from Webb to Judy to Leclerc and then back to Judy. He rested his rifle on his forearm.
“One thang I kin shorely tail is y’all ferners.” He paused, his face expressionless. “Y’ain’t bin spyin’ on us, have you now?”
The Barringer Crater, Northern Arizona
The man stood in shadow, on the floor of the giant bowl, shivering in the cold desert air. Six hundred feet above him, sunlight was illuminating a thin strip of clifftop and creeping down the rock face. He willed it to go faster, but the laws of celestial mechanics remained unmoved. A green lizard looked at him from an eye at the side of its head, and then scurried along an abandoned girder where men long dead had once tried to reach down to the nickel-iron meteorite they thought was buried far under the ground. The chopping sound of the helicopter high above faded as the small, bright blue machine disappeared over the rim of mountain.
The man turned to his companion. “Are there snakes here, Willy? I hate snakes.”
“Welcome to the Barringer crater, Jim,” said Shafer. “Ever been here?”
McNally looked around at the bowl surrounding them. “Seen pictures of it. Please say there are no snakes here.”
“Snakes are not an issue here, Jim. Not like they are in New York, where they smoke crack and carry guns.”
McNally looked relieved. “I believe you, my feel-good index has just gone up.”
“Now the scorpions, that’s another matter.”
“Thanks a million. Why are we here, Willy?”
“I thought a big hole in the ground might lend a little spice to our deliberations. Anyway, genius makes its own rules. We’re a small club, the rest of you can only look on and wonder. Let’s do the tour.”
McNally turned slowly like a lighthouse, gazing at the circular wall of rock which rose six hundred feet above him on all sides. Then he set out after the physicist, making for the base of the wall a few hundred yards away.
“Some impact,” McNally said.
“A penny firecracker,” said Shafer. “A few megatons about forty thousand years ago. There may have been people around.”
“So where are we at, Willy? Do we smash it to rubble with H-bombs?” McNally asked.
“Where did you get that from, Jim, your Los Alamos Workshop or a bad movie? Say you tried that and you ended up with a thousand fragments. Each one maybe a hundred yards across and coming in at maybe seventy or eighty thousand miles an hour. The bits would drift apart slowly but they’d keep close to the old trajectory. By the time they reach us they’d come in as a spray, countrywide. Instead of a rifle bullet you get buckshot, coming in over a few hours. So you don’t get a million megaton shot, you get a thousand impacts instead, each one with fifty thousand times the energy of the Hiroshima bomb. Ungood.”
“I’m still trying to get a handle on this,” McNally admitted.
“Think of America on the receiving end of a nuclear attack. Then multiply by fifty.”
“So let’s take it a stage further, literally pulverize it. Could it be done?”
Shafer started to scramble up the steeply sloping inner wall. “Depends who you listen to,” he called down. “One school of thought says the Earth-crossers are just dried-out comets, maybe even just dust balls. In that case, maybe you could. That’s the Webb line. Sacheverell thinks otherwise. He says they’re strays from the main belt asteroids between Mars and Jupiter. In that case they could be rock or iron and no way could we deliver the energy to smash one up into dust.”
“What’s your view?” McNally asked.
“There was this Crusader,” said Shafer, sitting down. “He wants to show off his strength to a Saracen. So he gets this iron bar and swipes it with his two-handed sword, and the iron bar breaks in two, and he says beat that if you can. So the Saracen gets a silk handkerchief and he throws it up in the air. He holds the blade of his scimitar upwards, and when the handkerchief floats down over the blade it splits in two.”
“That is very poetic, Willy. I like poetic stuff, I didn’t know you were a poet as well as a genius. Maybe if I had a Nobel prize too and a head full of parables I would get your drift, but you see just being an ordinary Joe with an ordinary-sized hat who’s frantically trying to save his country, the significance of this poetic story passes me by.”
Shafer grinned and threw a fist-sized stone playfully down at the NASA administrator. “That comes from running big bureaucracies. Loosen up, Jim, think lateral. So if the asteroid is rocky, when it comes in it hits us like a two-handed sword and we’re blasted to hell. If it’s a dust ball, and we turn it into a powder with bombs, the dust floats gently down like a Saracen’s handkerchief and cuts off our sunlight. We could end up with a few billion tons of dust dumped into the stratosphere. If it’s sub-micron, like condensation from vaporized rock, it blocks out sunlight and we go around in deep gloom. It takes a year for dust to settle out and meantime we’ve killed off commercial agriculture. So our food chain collapses. Experience shows that people without food eventually die. That’s your Saracen option, Jim.”
“If I could corner the market in canned beans… is that lateral enough?”
Shafer clambered down and the two men began a circuit of the Barringer crater. “Forget about pulverizing Nemesis,” said the physicist. “The only way we can handle this is to knock Nemesis off course the same way it was knocked on. We need a controlled explosion.”
“You mean use the debris from the explosion like a rocket exhaust?”
“You got it.”
“How much would we need?”
Shafer glanced at his watch. “I’ll be showing some calculations. If we had ten years’ advance warning, we’d only need to shift Nemesis by a centimetre a second, about the speed of a fast snail. The long-term orbital drift does the rest.”