Martian Rainbow

by Robert L. Forward

  The string of metal spheres stabbed down into the soil. Their kinetic energy turned into heat as they plowed to a stop, and they blew up like a line charge of dynamite. A butterfly-shaped cloud of dust and rocks rose from the ground and shot into the air, where it would stay for weeks. A shock wave spread out to encircle the planet. It was felt with trepidation by the humans huddling in the underground shelters, but the hundred billion Lineups that now covered both polar regions continued to dig and eat the icy dirt without a pause.

  CHAPTER 19

  Mars Reborn

  "THE RADIO signals just stopped, sir," the tech said sadly.

  "That's what comes from trying to fly at low altitude," Gus said resignedly. "Especially in a region where there may now be a mountain where there used to be a valley."

  "Shall I send in another RPV, sir?" the tech asked.

  "No," Gus said. "The dust is still too thick. Too thick to risk a manned hopiter, too. We'd better go in on land."

  Gus put on his Turner Turbomask and switched it to the pre-breathing mixture to clear the nitrogen from his system as he walked down the long underground corridors in Mutchville to the motor pool area. The outer buildings at Mutchville had been depressurized from the original half-atmosphere pressure to a third-atmosphere. Now people who worked outside could switch back and forth between the quarter atmosphere around Mutchville at the bottom of Chryse Basin and the slightly more comfortable third atmosphere inside without having to put on Marsuits. There were some sensitive types, however, who couldn't take the low pressure—and it certainly stressed the children, who spent most of their time in the half-atmosphere core buildings where school was held.

  Gus checked the sensors in his turbomask as the airlock went through its cycle. He was still putting out a lot of nitrogen and shouldn't say outside too long. He switched the turbomask to pure oxygen and stepped outside onto the surface of Mars. The sky was still the dark rusty red it had been for the last four weeks, with only a brighter area in the sky where the noonday Sun should have been. He walked past the greenhouse balloons, brightly lit from inside by the fluorescent lighting, his feet crunching loudly in the inches-deep dust and ashes still drifting down from the sky. It was cold and he hurried into the warmth and higher pressure of the motor pool maintenance hut to arrange for their journey south to inspect their new home.

  THE CRAWLER convoy from Mutchville worked its way across the equator through the Ares Valley, down past the Beer and Newcomb Craters, then started over the Hellespontus Mountains. Although their average speed through the Chryse Plains had been good, as they got into the more cratered highlands south of the equator, they were lucky to average ten kilometers per hour. It took almost three weeks of continuous driving to cover the six thousand kilometers to Hellas Basin.

  "I do believe the sky is getting clearer," Chris said, peering out the overhead dome in the cockpit section of the lead crawler. "I can actually see a disk where the Sun is supposed to be."

  "The ground isn't getting any clearer," Al Eisen said. "Nice fresh boulders everywhere. Our average speed is now down to five kilometers per hour."

  "What's that up ahead?" Chris asked. "Looks like something moving around in circles."

  "Could it be a dust devil?" Gus asked, getting down from the jump seat in back of Al and climbing up to the observation dome in the central section of the crawler. "Or worse?"

  "Moving too slowly," Chris said.

  Gus activated the telescope and zoomed in on the distant motion. "It's a cloud of flutterbats!" he said.

  "WE'RE GOING over completely new ground, now," Al said. "The crawler's map has a half-kilometer hill at this point, with the top at minus two kilometers below sea level, but our navigation system has us at minus four kilometers and dropping rapidly."

  "We must be starting down the crater," Jay said. "I wonder how deep it goes?"

  "Take it easy, Al," Gus warned.

  "The crawler can handle this slope easily, sir," Al said. "And the visibility is good out to a couple of hundred meters before the dust gets too bad."

  "Let me go outside for a background atmospheric measurement," Chris said, putting on his sweater and slinging on his turbomask. "I need to calibrate the crawler instruments to take out the contaminants coming from the crawler itself." He cycled through the airlock, went a few dozen meters away, set up his analyzer, stood back while it made a reading, then brought it back in. Above him whirled clouds of flutterbats.

  "Phew!" Jay said at the odor arising from Chris' clothing. "You smell like you have been rolling in a barnyard."

  "That's life on the new Mars for you," Chris said, reading out the display on his analyzer. "Total pressure 290 millibars. Oxygen 146, carbon dioxide 90, nitrogen 43, methane 11, and a trace of ammonia. It's the methane and ammonia that give the air its tang."

  "Cow farts and pig piss," Jay said.

  "But they make great greenhouse gases," Chris said. "And it's already working. It was actually six degrees above freezing out there."

  "Balmy," Jay said.

  "Down we go," Al said, starting the crawler moving again. Phyllis came over to Chris and looked at his sweater.

  "Hold still," she said. "What's this on your sweater?" She picked off a tiny brown waxy pellet.

  "Flutterbat droppings," Chris said. "The ground is covered with them."

  "Wonder what they contain?" Phyllis said to herself as she went to the analytical bench in the engineering section. A short while later she returned.

  "Carbohydrates and ammonium nitrate," Phyllis said. "Organic material and fertilizer. We shouldn't have any problems getting plants to grow in this ground."

  "I notice that the carbon dioxide, methane, and ammonia levels are all lower than what they should be for a well-mixed atmosphere," Chris said. "I think the flutterbats are converting them to useful solids, leaving just the oxygen and nitrogen for us."

  "From the smell, they have a long way to go," Jay said.

  "Coming up on a stream," Al said. They all went to the front to look out the window. A whole section of the hillside was wet with springs where the fracture zone from the impact had cut through the water table. From the base of the seep there flowed a good-sized stream that was cutting a virgin valley down the sloping side of a gigantic hole in the ground. Al led the three-crawler convoy on a ten-kilometer detour around the marshy slopes before they could continue on their way down.

  "TEN KILOMETERS below sea level," Al announced a few hours later.

  "We're halfway down, if the hole comes in at what I calculated it," Jay said.

  "Pressure up to 390 millibars," Chris said, "and a balmy thirty centigrade outside; don't even need a sweater. This would be a nice place to live."

  "Except for the smell," Jay said.

  "Well," Chris said, looking up through the dome overhead at the clouds of flutterbats that spiraled upward as far as they could see, "the flutterbats are working on that. Give them time."

  The stream had grown into a significant river. Twice, they were forced to backtrack and ford over when they came to a fork where the river joined with another one.

  "It's getting hotter," Phyllis complained. "Does this crawler have an air conditioner?"

  "Are you kidding, Phyl?" Al said. "Heaters we got. The makers never thought we'd need air conditioners on Mars."

  "Say!" Gus said, pointing slightly upward through the clouds of circling flutterbats that grew smaller as they faded off into the dusty ah. "I think I see the other side. We must be coming to the bottom." Sure enough, off in the distance they could see the dark meander of a stream coming down the opposite slope a number of kilometers away. Al took them further down-slope. The air, full of busy flutterbats, became clearer and clearer, until finally they could see the surface of a body of water far below. In the center of the brown steamy lake was a small peaked island.

  "Splash Lake," Jay said. "Just where it ought to be, sixteen kilometers below sea level. Right now it's muddy and ugly and hot, but soon it'll be the resort
spot of Mars."

  "My prediction for the temperature down there is fifty-four Celsius," Chris said, "with a humidity to match. A veritable equatorial jungle. It would be a great place for plants, but I think I'll wait until it fills up to a more temperate level."

  "It's hot and damp and smelly, but it's home," Gus said. "Let's call the 'bomb shelters' and tell everybody to start packing up the moving vans."

  GUS LOOKED down out the picture window in his new office at Dugout City to Splash Lake lying far below, surrounded by the lush fields and gardens of New Brazil. The huge pane of thin plate glass for the picture window had come from a window-glass factory started by some entrepreneurs, now that air pressures had risen to where unpressurized buildings were feasible.

  Off to the left he could see Westside River meandering down through the young forests covering Westside Slope, while ahead of him were the lush pastures of New Switzerland, dotted with tentlike pens of grazing sheep, goats, rabbits, and barnyard fowl. The clear plastic tents were weighted down around the edges by large-scale versions of the Turner Turbochargers, for the animals were just as sensitive as humans to carbon dioxide. He watched as a crew of animal tenders moved a tent full of goats to a fresh patch of thick green grass. They still had no cows—Earth was still not communicating with them, much less sending cow embryos. It was recess time at the institute day school, for the hillside below him was covered with running and laughing children, each with his or her personal Turner Turbomask.

  Some cumulus clouds were building up at the far end of the lake, where the Sun had been reaching down Eastside Slope to heat the already-warm waters. There would probably be the usual afternoon rainstorm. Above, on the surface of Mars, it was cold and frosty as winter started in the southern hemisphere, but down here in Dugout, the warm waters of Splash Lake always kept the small band of humans warm and safe. He turned to go back to his desk to tackle the problem that still awaited him there.

  Cario Vulpetti's accelerator team had finished building the first section of their antimatter factory down Ius Canyon. Should they start on a second section or work on an accelerator breeder to make fissionable fuel for the nuclear reactors instead?

  Just then Fred Whimple interrupted.

  "There is an important message from the Mars underground through our Tokyo laser link," Fred reported. "It's on your message file."

  Gus pulled up the message. It was from Tanya.

  ALEX HAD minor stroke Sat night. Pleaded with Jerry to turn off Mace. Says controls respond only to Alex. I was able to pull Alex through enough to get his hand on globe Sunday. Alex better now, but still obstinate—refuses to believe he might die. Can you talk sense into him?

  THE TERRIBLE dream of the world exploding into a ball of lava came unbidden again to Gus and he could almost hear the echoing laughter of the Devil as he accepted the Devil's offer of a world.

  Suddenly Gus was racked with a physical shiver of guilt and fear. He had accepted a world—Mars—and was now gloating over its beauty, while all the time Earth was but a heartbeat away from complete destruction.

  He doubted that he could do anything to sway his brother—obstinate was inadequate to describe him—but he had to try.

  He touched a few icons on his screen and soon was in touch with Tether Control on Phobos.

  "I'll be taking the next tether shuttle up," he said." Get ready to activate Project Fireball." He reached into his desk drawer and took out the violet one-thousand-Mars-dollar globe coin lying there. "Fred!" he called at the comm unit. "Could you come in here, please?"

  Fred Whimple came meekly through the door. "Yes, Dr. Armstrong?"

  "I'm going on a trip. A long one. I'd like you to run the institute while I am gone."

  "I'll be glad to, sir, as long as I can reach you for important decisions."

  "I'm afraid that will be impossible, Fred. You'll have to make all the decisions yourself—even the important ones."

  "I can't do that!" Fred said, his chin dropping and his eyes widening. He started to shake in fear at the thought of all that responsibility.

  "You can do it, Fred," Gus said firmly, getting up from behind his desk. He motioned to the chair he had just vacated. "Please sit down here."

  "I couldn't do that, sir."

  "Please," Gus repeated. Fred came over and slowly sat down at the desk.

  "Now, as you know," Gus said, "the badge of office of the Governor of Mars is the violet one-thousand-dollar globe coin."

  "Yes," Fred said. "I have seen it. The only one ever made."

  "No. There is one other." Gus held up the large, thick, violet-colored coin in his left hand and rotated it with his mangled thumb and finger so Fred could see both sides.

  "It belongs to the director of the Sagan Mars Institute," Gus said. He handed the coin to Fred, who took it with a hand that trembled at first, but which steadied as he brought it closer to look at it.

  "It's yours now," Gus said. "With that coin, you have the authority to make whatever decisions need to be made to run the institute. You can even command the Lineups.

  "Of course," he continued, "it wouldn't really do to flaunt it about ... sort of detracts from the authority of the governor of Mars."

  "Yes. Of course," Fred said, smiling conspiratorially. He put the coin in his vest pocket.

  "If you'll bring up the 'In' file on the console, you'll find your first problem waiting for you," Gus said. Fred quickly touched a few icons and the problem was once again on the screen.

  "The solution to that is obvious," Fred said quickly. "Mars needs mobility more than fixed power sites. With the temperature rising and the ice melting, we'll soon have plenty of hydroelectric power and can hold the nuclear power plants in reserve. Why don't you tell—"

  "Why don't you tell them?" Gus interrupted. Fred looked up at him, a panicked look on his face. Then he reached into his vest pocket, fingered the coin hidden there, and firmly turned to the console.

  Gus went into the front office that held Fred's little secretary desk, picked up Fred's nameplate, and returned to the director's office. As he placed the nameplate on the desk and took his own off, he could see the last of the message on Fred's screen.

  Dr. Fred Whimple

  Director, Sagan Mars Institute (Acting)

  "If I didn't know it was made of diamond, I wouldn't trust it," Gus said, looking at the thin strand stretching out into space away from Phobos. The diamond tether was zooming by below them as they rode it outward, braking their fall in the centrifugal force field by transferring energy to the superconducting cable wound in a spiral around the diamond tether core. They shot though the Deimos transfer station at the 940-kilometer point. A capsule released at that point would fly out to the inner tether hanging down three thousand kilometers from Deimos without having to use any fuel. They continued on to the launch station at the end, some one hundred thousand kilometers distant, passing Deimos' orbit at the fourteen thousand kilometer point.

  "Since the orbital inclinations of the two moons are almost a degree different, Deimos only gets near the tether a few times each mear," the capsule pilot said. "Then we twang the first vibrational mode of the tether just enough to avoid hitting it."

  Six hours later they were standing in the half-gee centrifugal acceleration of the end station. The strange ship of Project Fireball hung waiting at the bottom of the station.

  "It'll be like living in a telephone booth for a month," Gus said grimly as he climbed down through the graphite tanks full of water and into the small central compartment.

  "The smaller it is, the less likely it is to be noticed," said the engineer helping him with his equipment. "I made sure the central computer memory has plenty of books in it, plus all the information I could dredge up on Cyprus. Good luck, Gus."

  "I'll need it," Gus said, closing the hatch.

  Shortly thereafter, the swing of Phobos in its orbit was at right angles with the far-distant Earth. Grapples released and Gus shot off toward the inner solar system at twenty
-three kilometers a second, higher than escape velocity from the solar system. If he missed Earth, he would never come back.

  Now that the capsule was in free fall, specially designed nozzles released the stored water in a controlled spray that covered everything in tens of meters of dirty, frothy ice. Soon, another insignificant comet was on its way to a blazing death as a momentary fireball in the upper atmosphere of Earth.

  CHAPTER 20

  The Left Hand Of God

  THE BRIGHT streak of a falling fireball burned itself out in the upper reaches of the moonless sky. The radar warning net that surrounded the Island of God took note of the blazing column of plasma, trailed it for a while, since its trajectory was a little unusual, then dropped it from notice as the fireball seemed to break into pieces that were too small to reflect radar well.

  The still-glowing pieces of the heat shield broke up around him, and Gus had a momentary sense of fear as the cocooning couch that had been surrounding him also began to come apart. The insulating, foamlike layer covering his spacesuit not only kept the heat out, but absorbed practically everything electromagnetic in the radar bands. Gus looked down at the uprushing Earth. Through his darkened visor he could see his glowing feet creating a shock wave of phosphorescence in the rarified air. Beyond them were patches of light from the cities below.

  The glow around his feet faded away as the diamond-glass cable tethered to the massive "comet head" thousands of kilometers above pulled on his harness and slowed him down. The visor on his helmet adjusted automatically to the light level, and he could now make out the illuminated main road that ran around the island ahead. Minutes passed and Cyprus loomed large ahead of him, with Turkey off to the right. He pulled down the infrared visor and the scene turned from blackness to phosphorescent light, as if he had turned on an artificial green moon. He was falling more slowly now, as the slowly tilting cable brought him down closer to the surface. The timing had been good. He was going to land in the water just offshore of Limassol. The automatic ultrasonic altitude indicator came on, and he felt the motor in his harness hum as it reeled cable in. His feet were now just inches above the rippling waves. He skimmed across the water toward the shore, the cable reel singing as it sucked in cable to keep him above the surface. He found the blinking blue light that marked the end of a long unloading pier that stuck out into the water.