David Brin - The Heart of the Comet

The irony of the Uber -Plateau Three alliance was that now the Arcists had virtually destroyed both options.

To bring off a good Jupiter flyby on the inward-falling leg, they had to use the south-pole flingers. And the Arcists wanted above all costs to keep Earth pristine and safe from Halley contamination. If the Jupiter encounter came off badly in the crucial hours of encounter, Halley could be flung deep into the inner solar system. The Arcists would never go for a maneuver that brought Halley near the home world. To avoid that possibility, they would refuse use of the south pole unless they were in control. Quiverian and his fanatics would rather die in deep space than let anyone else handle the maneuver.

He read the signs, and knew that the situation was close to war. If something wasn’t done, soon, there would be killing. So Carl had sent a squirt Earthside as soon as he returned… and gotten confirmation. He had to offer a good option to the Council, now, before factionalism made compromise impossible.

Even if I have to fudge the truth…

He waited for a natural break in the talk. The wall weather now showed a sloop tacking in high seas, her stately turn unhindered by glistening steel-blue waves that hammered her without pity or effect. Her sails billowed triumphantly, shimmering white beneath a hard cold sky. She’ll make port, he thought. You can see it in the way she moves.

He let the talk run on for while. When the silence of confusion and doubt came, s he knew it would, he rose and began to speak. He caught and held the eyes of each faction leader in turn—Otis Sergeov hanging legless in air, arms folded adamantly; Joao Quiverian here under a truce, as solid as ever, eyes smoldering; Jeffers, who represented the Martian Way group, lean and sardonic; and the others, who had no particular politics, but did want a chance to live.

Carl spoke slowly, conveying by gesture and expression more than through words the hope he had, the plea for confidence, for solidarity before this new threat.

“This mission was planned around a planetary carom past Jupiter. That’s why we put launchers at the south pole— which are now unusable.”

That put Quiverian on the spot. The others glared at the sallow Brazilian. Of course, Carl wasn’t quoting the man precisely. He hurried on before Quiverian could interrupt.

“But the south pole Nudge isn’t our only option.” He flicked a tab on his sleeve and a chart appeared on Central’s main screen. “It would take a relatively simple Nudge to reach Earth itself. A change in velocity of only sixty-three meters per second, aimed about forty degrees south and nearly ninety degrees away from the sun would bring us home.”

The men and women stirred, varying emotions flickering across their faces. Home.

“But to do it accurately demands that we despin Halley first. We’d arc in near Earth, good for a quick jumpoff and rescue… but only after perihelion passage. We’d have to weather that terrible storm. It’s anyone’s guess how many of us would survive high summer on a comet.”

He had let the frowns and scowls build; now he defused them. Quiverian was red as a beet, opening his mouth. Carl cut him off.

“Of course, Earth Control might get a bit miffed…”

They looked at each other, blinked, and guffawed. Their laughter released some of the long-building tension. Of course Earth would never allow a plan that brought Halleyform spores that near the atmosphere. Even Quiverian relaxed slightly, when it was clear that Carl had not been serious.

“There are other alternatives to Jupiter,” Carl continued. “We could try for Venus— jump off in aeroshells, decelerate in the upper atmosphere. But that’s after perihelion again, and we might not survive slamming into that atmosphere at eighty kilometers a sec or so.”

He swept the room with a long, penetrating gaze. Cap’n Cruz would’ve done this right , he thought. Or maybe he would’ve stopped all this factionalism long ago. I’ll never be the leader he was.

“On the other hand, there is an encounter that’ll get us to a planet before perihelion, and at lower velocity— one with Mars.”

A stir of disbelief. “Mars?”

“You mean target… ?”

“I didn’t know it could even be…”

He went on swiftly, not giving anyone a chance to break in.

“Look. We can’t allow a single faction to control our destiny—”

“And we will not allow use of the south pole unless we have control!” Quiverian shouted.

Carl held his palms up, open. “Okay. That means we have to abandon the Jupiter flyby totally. The next best mission demands a pass into the inner solar system, but not coming near Earth. Instead, we can vector the Nudge to Mars. The encounter itself won’t divert Halley much— but it’ll give us a chance to jump off.”

Some engineers shook their heads. Carl kept on going, before the objections could begin.

“We’ll build aerobrakes and swoop into the Martian atmosphere. It’s thin but deep, a good target for us, especially since an encounter with any planetary atmosphere will be awful damn fast.”

A spacer asked, “We could lose enough velocity on one pass?”

Sharp question. “No. We’d have to do several maneuvers.” He ticked off fingers. “Aerobrake at Mars, divert outward to Jupiter. Aerobrake again there with a gravity assist. Pass inward to Venus, swing around, head for Mars again. By then we’ll have shed enough velocity to make a successful rendezvous brake in the Martian atmosphere. We can get out of the aero shells, come alongside Phobos.”

A long silence. They stared at him.

“But…” Keoki Anuenue muttered. “How long will all that take?”

“Twenty years.”

Gasps.

Carl rode over the babble with, “That’s twenty added to the nearly eighty we’ll have been gone. But it will be worth it to get to Phobos Base, to safety and maybe eventually, home again. I should add that this plan has the approval of Earth Command.”

A Plateau Three woman said angrily, “What’ll happen to Halley?”

Carl shrugged. “JonVon shows it wheeling off into the outer system, back to its original home in the Oort Cloud, gone for good.”

Jeffers said thoughtfully, “We could target Halley smack on Mars— give it an atmosphere!”

“Sure,” Sergeov said, “and try aerobraking at same time. Impossible!”

Jeffers began, “But—” He shut up as he noticed Carl’s signal to be quiet.

“It’s a chance to live,” Carl said emphatically. “ If we try the aerobrake and guide Halley to optimize that. Anything else is suicide.”

“What can we expect at Mars?” Quiverian demanded suspiciously.

“Quarantine. Maybe Earth’ll order us isolated on Diemos. Let the medicos study us until Earth is sure these diseases are controllable.”

Another long silence. They all contemplated this new idea, letting it sink in.

“Is possible?” Sergeov asked, scowling.

Carl shrugged. “We might never be allowed into Earthspace— not that that’ll bother the Ubers, eh? Remember, though, that there are decent places to live in the small scientific colonies of the asteroids. Maybe we can even do some worthwhile pioneering on Mars itself.”

Jeffers beamed. “Damn right.”

Carl held up his hand. “One more thing. Earth Command is very strong on this plan. It has made acceptance a condition for getting the Care Package.”

That got to them. The high-speed rocket carrying supplies was the centerpiece of their fresh hope. They had to have it.

Carl realized that the hardest part had been won.