Rainbow Mars

by Larry Niven

  “Yes.”

  “Range?”

  “How heavy is your probe module?”

  “Pilgrims mass one hundred fifty tonnes, rocket and all. Twenty-two meters long, twelve meters diameter. I can assemble them in three months if you want them.”

  “That’s tiny compared to Whale.”

  Gorky nodded. “I’ll work out how many modules we want. We’ll push the small X-cage back to before the Lowell observations—”

  “Willy, will you settle for –550 AE? Seventeen hundred years ago, around five hundred years before Lowell.”

  “Middle Ages. Why?”

  “It’s when Svetz picked up Snake. Before the American continents got into the history books. Nobody local will bother us if we operate over the open Pacific. The time machine wouldn’t have to be reset. That saves us a week, and funding too, Willy. You build your Pilgrims right, they’ll just sit on Mars with their cameras running, right through the Lowell and Mariner periods.”

  “All right. The large X-cage homes on the small one? Good. Once you’re in orbit you’re halfway to anywhere.”

  Organization was a skill Svetz had never tried to learn. It wasn’t enough that things happen. They must happen in the proper order. Rocket motors must appear before a hull could be closed. Fuel couldn’t just sit in a tank; compressors must be ready to produce it at the right time. Why was timing so difficult for the Institute for Temporal Research?

  Svetz sat in on endless discussions—

  “Now, here’s the tricky part,” Ra Chen told Willy Gorky. “We launch the first load, then pull the big cage back empty. We load your next module inside, and we can take our sweet time doing it. Days, weeks, a year if there’s a budget cut. Then we send it back to Miya and Svetz in the moment following the first launch. Launch again the same way. Or send it back to ten hours later, give them a sleep break.”

  “You can do that?”

  Ra Chen smiled a fat ruddy smile. “Time travel is wonderful, isn’t it?”

  * * *

  Three months stretched to four, and wouldn’t stretch further because the Secretary-General’s annoyance was becoming overt. And one morning they were ready.

  6

  The new extension cage was transparent nearly to invisibility. It was no smaller than the old extension cage, which had once held Svetz and an angry Horse. But Svetz and Miya were nestled in the bottom of a spherical shell, and that might have felt cramped—

  “Cozy,” Miya said. “Why isn’t one of us in the control chair?”

  Svetz smiled. “You’ll see when we get moving.”

  She nudged Svetz’s bag with her foot. “What did you bring?”

  “Food, medical, and the trade kit. You?” He waved at the upper curve, where bubble helmets and the pelts of two rubber men were splayed out on stickstrips. “I haven’t trained with pressure suits.”

  “If we have to go EVA, I’ll take you through it slow and thorough. Trust me.”

  They lay foot-to-head, waiting while the Center milled around them. Svetz had become very comfortable with Miya. Her head was pillowed on his foot. He felt his own long, wispy hair brushing her ankle. He’d considered suggesting greater intimacy, but—as often in his life—he was afraid of losing what he had.

  Through the open hatch he heard a murmur of techs and hum of the motors, and:

  Gorky: “There never were canals on Mars. Miya’s always been a bit flaky about canals.”

  Ra Chen: “Willy, you should have done this years ago! Pick up some Martians and you’ll never have a problem with the SecGen again. You’d have Martians voting your ticket in the UN! Futz, you’d want to know what they knew about terraforming, too! Mars wasn’t supposed to stay habitable that long, was it?”

  Gorky: “We should look at Saturn’s rings too. They’re recent.”

  Ra Chen: “How recent?”

  Gorky: “A few … hundred thousand years. Never mind. This is already costing too much! Antigravity, pfah!”

  Ra Chen: “Antigravity beamers came from Space Bureau. Don’t you always launch by antigravity?”

  Gorky: “Oh, no. It costs four hundred a kilogram to launch with rockets. It costs a thousand to lift the same kilogram with antigrav. When Svetz lifted Whale into the big extension cage, that must have killed around three thousand people.”

  Ra Chen: “You said that before. Killed how, Willy?”

  Gorky: “Lights brown out in an operating theater. Food half spoils but someone eats it anyway. Somebody can’t afford to repair his floater, but he has to get to work. A construction company buys cheaper supporting girders for a new arcology. The money runs out on building a nuclear fission plant, but the power has to come from somewhere, so they burn coal. Soot winds up in a hundred million lungs, and there’s more rads in it than they’d get from the fission plant.

  “When wealth goes down the death rate goes up, even if you don’t have a unique corpse to identify. Poverty kills. Most politicians have no idea what things cost. It’s a United Nations tradition. But Waldemar Eleven, he’s very aware of that. When a bureau diverts power and resources, people die. What he really wants, even more than that futzed portrait—”

  “What’s in the trade kit?” Miya asked Svetz.

  Svetz withdrew his attention from the talking Heads. “It turns heavy metals to gold. It’s easier to carry than gold. Look, you just enclose something in this superconducting net part and seal it—”

  “What’s making you so twitchy?”

  Svetz tried to relax. Tried to look relaxed. “I can’t see why all this took four months.”

  “You know, you can wait two years for a trip to Mars. Earth and Mars have to be placed right, and they don’t move at your convenience. If you miss your window, you wait.”

  Svetz said, “The last trip I made, they pulled me out of bed at just past midnight. By five I was on my way. Waldemar the Tenth wanted a spotted owl. He wanted it now.”

  “Did he get it?”

  “Miya, if the Industrial Age lists it as a protected species, we can’t find it, unless it’s a bison or a passenger pigeon. I was lucky to find any owl. It was somebody’s pet, and she had some spooky weapons, really high tech. Someone from our future, I think.”

  “I’d love to think we have a future.”

  The pale-skinned tech named Zat Forsman lowered the big curved door and sealed them in.

  Svetz said, “So we spray-painted spots on the owl—”

  Everything went blurry. There was a flow of colors and textures, but no detail came through the glass. Miya started to ask a question, then trailed off as gravity changed.

  They floated at the center of the sphere.

  “If you were in the chair, you’d be hanging head down,” Svetz said. “It’s reversed when you’re coming home.”

  “How long before we stop?”

  “Mmm? Two hours. You were at the briefing.”

  Miya asked, “Who were the first human beings to have sex while traveling in time?”

  “Nobody, I think. No, wait, there haven’t been any mixed couples. Nobody.”

  “Great!” Her hands moved into his clothing.

  Svetz had never had an offer that straightforward. He asked, “We’re going for a record?”

  “Hanny, dear, Captain Thale and I weren’t the first in free fall by a thousand years!”

  They hung their clothing on the inverted chair. Internal gravity pulled them together and held them. Miya fitted them together as if she’d done this before, and that left them at right angles in midair, hip to hip and laughing like loons.

  7

  “That was different.”

  “Isn’t this just like free fall?”

  “In free fall you just float.”

  “Oh.”

  “Are we being recorded?”

  “Hadn’t thought of it. We can ask,” said Svetz.

  The four months’ wait hadn’t been wasted. High-tech devices from Space Bureau had been adapted for the extension cages. They had a voic
e link now, but no video. Svetz pulled himself up to the control board, opened the talker and said, “Svetz here, in transit, nothing to report. Testing—”

  He heard Willy Gorky’s voice. “Good.”

  “Sir, are you video-recording us?”

  “Video and medical, but we’ll get the data later. The talker only carries audio. You have to tell us everything.”

  “Excellent!” Miya caroled, and switched off.

  “So. You’ve got your record.”

  “Look at me.”

  Svetz looked.

  “Four months and you never touched me.”

  “Sure I touched you—”

  “Never this. Never anything. Zeera keeps her distance from other men, so I wondered, but she doesn’t brush up against you either. I wondered if you had something esoteric going with Wrona—”

  “Hey.”

  “What kept you, Hanny? You could have had me in a bed.”

  “A bed? Ooo.”

  “Think of all the practice we missed.”

  “We did pretty well.”

  They were floating apart. Svetz said, “Grab something,” and grabbed at the chair. Miya grabbed Svetz, and then they were sliding down the glass curve of the cage in roaring darkness. Sudden sputtering light illuminated a wilderness of whirling cloud.

  Svetz crawled up into the chair and jabbed the talker. “We’re here,” he told listeners in the far future. “Nothing to see. We’re in a hurricane, typhoon, whatever.”

  Willy Gorky said, “That was quick.”

  Svetz heard strangled laughter and rapid explanations. He saw Miya’s lifted eyebrow and said, “Far as they’re concerned, we just left. I’m taking us up now.”

  They couldn’t feel the cage lifting. Texture in the darkness streamed past them, then the Moon blazed above a mountain of cloud, lightning flickering within.

  The storm dropped away. The sun flashed over a horizon now curved. Miya said, “Wow.”

  “Eight hundred klicks and no problems. Thousand. Twelve hundred,” Svetz said. “Don’t look at the sun, Miya!”

  “I know that!”

  The Earth was a blazing crescent. “Fifteen hundred klicks. How high do you want me?”

  Ra Chen’s voice: “Are they high enough?”

  Gorky: “No. Can you get at least to geosynchronous? That’s 35,700 klicks.”

  Svetz: “I’ll try.” He waited, watching the altimeter. Minutes passed.

  “I’m at 35,700. Stop here?”

  Ra Chen: “Just because you can get higher doesn’t mean the big X-cage can. Svetz, stop there. We’re sending the large extension cage.”

  A great glass sphere hovered beside them in the instant Ra Chen finished speaking. Miya flinched, then said, “What took so long?”

  “It’s here,” Svetz told his listeners. The first probe module nestled inside the big transparent shell. He tap-tapped, and the shell opened like a flower. “Look it over, Miya.”

  “It’s the Orbiter. We want it in a pole-to-pole orbit around Mars.” She reached past him and activated the launch.

  The probe lifted. In seconds it was gone from sight, but Svetz could see the large extension cage shuddering, the antigrav beamers turning to follow it.

  * * *

  “We’re pulling the large X-cage home,” Ra Chen said.

  “Good,” said Svetz, and the great mass was gone.

  Miya broke a small dark brick and handed half to Svetz. “Ration bar.” She bit into her half. She saw his distrust and said, “It’s dried dole yeast. I’ve got twenty flavors here.”

  He bit. “Not bad.”

  The link chimed. Gorky’s voice: “Miya? We’re go for the next load. Ready?”

  “Boss, how did you … never mind,” she said, and laughed.

  Willy Gorky laughed too. “Quick enough for you? Took us three weeks to assemble the Collector module and get it aboard. Shall we send it now? Or give you some nap time?”

  “Now,” she said, and the large extension cage hovered beside them with the Collector and fission rocket booster inside.

  * * *

  The Collector was a low-built tractor with a chemically fueled rocket in its belly, mechanical arms and a pressure storage bin. They launched it, then took a break before launching the third and fourth. Miya kept up a running commentary.

  The Orbiter would go pole-to-pole above Mars and relay messages from Pilgrim probes on the surface.

  When the Collector returned a cargo to orbit, the Orbiter would carry it back to archaic Earth and a waiting X-cage.

  The third probe held twelve toy-sized Pilgrims. Those would wander out in twelve directions from the martian equator. Their senses would watch and listen and taste the soil and the wind—“Hanny, I’m not getting enough thrust here. The Pilgrims mass too much.”

  “I can’t keep the large X-cage. Ra Chen, pull it back.”

  “We need”—the large extension cage vanished—“more thrust!” Her small fist whacked his shoulder.

  Svetz said, “Talk to her, Boss.”

  “Miya?” Ra Chen’s voice. “We’ll put the large cage through maintenance and send it right back.”

  “The Pilgrims will be gone in a—oh, here it is again.” She watched the great sphere’s antigravity beamers turn toward the third probe—carrying the Pilgrims, now far beyond sight—to boost it into course for Mars. “I could get used to this.”

  The Collector would need fuel for takeoff. The fourth probe, the Tanker, would land near the peak of Mons Olympus and use its nuclear power plant to convert martian atmosphere and six tonnes of liquid hydrogen into ninety-six tonnes of methane and liquid oxygen. Martians weren’t likely to bother it there—

  “Why not?”

  “Life on Mars—even Mars—probably evolved in water. Mons Olympus pokes right out of the atmosphere. Okay, Hanny, it’s on its way. Jump us.”

  * * *

  Earth and stars blurred like paint in water as the extension cage entered time. Gravity was outward, away from the sphere’s center, as they were pulled toward the present. Miya looked at him speculatively across the width of the extension cage.

  Svetz grinned. “No time.” He watched the inertial calendar for a few moments longer, then pushed the Interrupt. “We’ll have longer going home. Yes?”

  “Yes, my hopeful swain.”

  Swain?

  The hurricane was gone. From fifteen hundred klicks’ altitude the Earth’s broad crescent was otherwise unchanged.

  Miya took the controls. The antenna pattern painted across the surface of the X-cage shimmered as it called across three hundred and fifty million klicks to machines that had been crawling across Mars for three long years.

  “That’s done. Mars is about twenty minutes away at lightspeed. Forty minutes before we get a signal. Can you jump us?”

  “No. We’ll have to wait.”

  “Fine.”

  “We’re nowhere near that accurate, Miya. We can’t place a cage within a year unless it’s matching locus with another cage.”

  Forty minutes later … all Svetz saw was the shimmer in the antennae, and Miya’s hands moving. Miya called the Center. She got Gorky.

  “Chair, we have message bursts from all four probes.”

  “Bring them home.”

  “The probes are all waiting for new instructions.”

  “Miya, we’ll have to decide what to tell them first. Come home.”

  8

  The Norse mythological world tree, Yggdrasil is an evergreen ash tree which overshadows the whole universe.

  —“The Ash Tree,” from Mattiol’s Commentaires, Lyons, 1579

  The whole of the Bureau of History and nearly as many from Bureau of the Sky Domains were crowded into the viewing room. There weren’t enough seats. A crowd sat cross-legged ahead of the front row.

  The Orbiter view showed red Mars strung with threads of gray-green six to eight klicks in width. Spectra showed lines of chlorophyll and water. Gorky protested, “They’re too narrow. How coul
d any optical telescope have seen that? Those old astronomers must have been going on nothing but intuition!”

  “They got it right, though,” Miya said. “Shall we call the SecGen?”

  “Not yet.” Willy Gorky shifted to the refueling module, the Tanker. They watched the mountain’s vast crater come up (flash!) and past. The Tanker settled onto a wide ledge. The fission plant trundled out on an array of skeletal wheels, trailing cable, and stopped eighty meters away.

  Gorky studied the readings. “Full tanks. Now we know we can bring something home. Forsman, replay that flash.”

  Instruments on the Tanker module had looked into the crater during descent. A white flash washed out everything, and then the audience saw a skeletal structure of metal tubes and mirrors occupying part of the central crater. Spidery strutwork supported curved mirror surfaces hundreds of meters across.

  “Sculpture? Artificial, anyway,” Miya said. “You’ve got your aliens.”

  “Good.”

  “Boss, do you see that?”

  A floating flat something moved into view, distant enough to look tiny until Gorky zoomed. Then … an open flying vehicle with eight crew, possibly man-shaped, moving around the upper deck. “Pressure suits,” Gorky said. “No wonder at this altitude, but what holds it up? Lighter-than-air craft don’t fly without air.”

  They watched it glide over the crater rim.

  “I wonder if they saw the Tanker come down.”

  Ra Chen asked, “We want to talk to them anyway, don’t we?”

  “Bring a few home. Ambassadors to the United Nations!”

  “Kidnap?”

  “We know what happened to Mars. Anyone we can bring out is rescued! Can you rebuild a Vivarium cage to house Martians?”

  “Futz, yes. Just fiddle with the programs. It’s already set to make breathable atmosphere for pre-Industrial plants and animals.”

  “Excellent. What’s the opposite of genocide?”

  Ra Chen laughed. “Nobody’s ever needed one.”

  “Ra Chen, I’m wondering what we’d find if I sent a team to Mons Olympus in present time.”

  “Is it an active volcano? That could wipe out any traces … Willy, don’t do it. Knowing what’s there today would restrict our options in the past. What else have we got?”