by Colin Harvey
Good, Karl said. But you didn't need my attention for that.
No, Loki said. Also… I fired several clusters of micro-probes into Isheimur's atmosphere, and I've got their readings of the CO2 levels. They're far, far higher than they should be. But the probes have also confirmed something else – that for some reason, probably due to geodynamic mechanics, the planet's magnetic field strength is diminishing very rapidly – leaving the planet open to devastating effects on the volatile gases. What should have been global warming has given way to global cooling. Unless we can find a way to stop it, the settlers will die.
I don't believe in coincidences that big, Karl said. Find the smoking gun. How long do the settlers have?
I estimate ten to thirty years, depending on the rate of cooling and precisely when it began. Loki flashed up an image of Bera as an old woman, huddled in vain against the cold.
Karl wondered again at the Aye ships' presence, and tried to block out the image of Bera dying. He turned back to the others. "Something's arisen, involving Isheimur." He asked Orn, "If Loki can find the frequencies, can you access the Oracle?"
"You want me to break into it?"
"Yes."
"Why?"
"We need information." Karl repeated what Loki had said.
Orn looked around, and sweeping the dust off a flat surface that probably acted as a resting place for beverages – it seemed to serve no other purpose – took a marker and scribbled numbers on the surface.
"Can we talk to our wives?" Orn said.
"If we can get access, then yes," Karl said.
Karl stared at the numbers. After a few seconds which probably equated to hours, perhaps days in cyberspace, Loki came back: I'm in. I'm looking for matches to magnetic fields, climate change, carbon dioxide. Ah, here–
When Karl emerged from his inner conversation, he became aware that the others were watching him anxiously. "What?"
"Even for you, that was a long, long trance," Bera said. "And while you were talking with your invisible friend, doors started opening and shutting, and lights going on and off."
"Don't worry about it," Karl said, thinking, Sort that damned datarealm out, Loki! "Strap yourselves in and get ready to tour the Mizar B inner system. We're going comet-hunting."
"Why?" Arnbjorn said.
"I'll tell you when we get there," Karl said with a huge grin, hand upraised to forestall their protests.
Once Loki had selected their target and everyone had strapped in, Loki ended the Winter Song's spin – to the settlers' consternation.
"Don't worry," Karl said as they grasped at chairs, consoles or anything else that was bolted down, "we'll be under way in a few moments. Once Orn's let go of that panel." The settler had clutched at something that looked secure, but turned out not to be attached, and floated horizontally, with his thrashing feet straight out behind him and his face twisted by terror. Somehow Karl kept his face straight.
"Shame," Bera said, flashing Karl a tremulous smile. "I quite enjoy weightlessness."
"Then we'll do it again," Karl whispered on his way to his chair.
Her smile widened, her eyes glowed, and she bit her lower lip before saying, "Good."
Diagnostics show that we can run for weeks on full power, so we'll have ample time, Loki said. We'll run out of air before that, even with this ship's archaic CO2 scrubbers recycling it. They're not the most efficient kit that I've ever encountered.
"Could we run it through the nanoforge?" Karl muttered.
I doubt it. I've seen more sophisticated tractors than that forge.
Before Karl could reply, a giant fist punched him in the back, and they were under way.
Loki took them up to three gravities for almost an hour, until Karl took pity on the others, particularly Ragnar who breathed like a haddock out of water. Karl told Loki: Drop us back down to one standard g for an hour.
There was a long pause before Loki said, I am encountering difficulties with this idiot semi-consciousness again. Then the gravity slowly, steadily dropped. Executed.
Karl grinned. "That was said with great emphasis."
Indeed.
After another hour, they dropped back to acceleration at Isheimuri gravity for almost twenty-four hours. Mostly they ate and slept in the chairs they sat in, then stretched and paced the kinks out of their backs, before visiting the facilities.
During a lull in the internecine strife with the datarealm, Karl led a scavenger hunt through the ship; Coeo found some interactive holo-discs in Kazakh that had dropped down behind a chair in the crew quarters. He interrogated them for hours on end, devouring Terran history, astronomy, anything that he could access. Arnbjorn and Orn played cards with a pack that they'd found in the back of a cupboard, while Ragnar sat and brooded, staring into space.
Bera hunted and gathered ragged remnants of fabrics, furnishings and equipment. "Are you nesting?" Karl joked.
She gazed at him with eyes that never blinked. "I'm planning for what happens when – if – we return to Isheimur. Remember our leaving Skorradalur?"
Karl nodded with a little smile. "I'll consider myself suitably rebuked for not thinking ahead."
"Quite right," Bera said, and then she slowly smiled. "You thinking at all is an improvement."
It was, Karl decided, the nicest smile he'd ever seen, but said nothing.
The rest of the time, Bera spent sleeping in the chair next to Karl, curled up in the crook of his arm. No matter how cramped, he rarely moved, for fear of disturbing her.
Loki said, We're just past the mid-way point, about thirtyseven million kilometres to destination. Do you want me to mirror the acceleration – Isheimuri, standard, then three standard for the last hour?
"No," Karl said. "Reverse thrust at Isheimuri standard for as long as possible. Let's keep it simple. It strikes me that the fewer changes we make, the less the Idiot fights us." Loki had christened the datarealm thus after one of its sporadic attempts to regain control.
That would seem to be the case, Loki said. Perhaps now that we're leaving Isheimur it believes we're returning to its original mission protocol. Our taking what would be the right course or simply reaching escape velocity has fooled it.
Or maybe, Karl thought, it's just biding its time.
During the deceleration, the others again probed Karl relentlessly about his plans. He remained closemouthed, partly because data was still pouring in, both from the first micro-probes that Loki had launched and from another subsequent batch.
So to distract as many of them as possible, Karl had Orn and Arnbjorn cut up the cockpit door that they'd blown in; he felt a little uneasy allowing them a lasersaw, but almost anything else aboard could be turned into a weapon, and his gamble had been vindicated. Given a practical task and when his world shrank to the nanoforge in the foundry, Orn forgot his fear, losing himself in reducing the door to forge-fodder. Given raw materials, the forge could produce pretty much anything not on the proscribed list, which precluded weapons and explosives. He even ceased pestering them for updates on communicating with the Oracle – Loki had had about seven seconds worth of access before the Oracle. Unable to reconcile his actual location with the Skorradalur co-ordinates embedded in Orn's access codes, he had slammed a metaphorical door on any further communication.
Bera used the forge to "cook", duplicating the samples of various meats and fruit that she'd carried aboard the ship. It seemed strange to Karl that the forge could manufacture complex micro-probes, but was incapable of producing lamb that didn't taste like rock-eater meat, and vice versa.
Karl also didn't want to answer the other's questions because until Loki had a chance to examine their destination in minute detail, he had become imbued with a superstitious dread that talking about the plan might jinx it somehow. He would have laughed at such prehistoric ideas back on Avalon, but Isheimur had changed him in many ways.
So when the others tried to get him to talk, Karl instead encouraged the settlers to talk to Coeo, and vice versa
. Isheimuri proved easier for Coeo to learn – for all that he had to remember to pitch his voice within certain narrow frequencies – than mutated Kazakh was for the settlers to pick up. Coeo's rudimentary Isheimuri soon improved markedly.
"Where did you think that the original Formers came from?" Arnbjorn asked.
"From hell," Coeo answered. "We thought the old stories passed down from mother to baby, that hell was beneath us, were wrong. We knew where we had come from – that our grandfathers had fallen from the sky and shaped the mud and the rain to make us. But when the sky opened and vomited forth your people, we thought that perhaps hell – as well as heaven – was above us." The adapted man paused. "Every day, every night, rocks rained down on us, screaming across the sky. Some of our people hid in caves, some beneath outcrops and overhangs. Most simply perished in the open, though. Then, when we tried to communicate, we were slaughtered. We were prevented from following our animals on their migrations."
Karl was privately sceptical that the comet-rains had been so concentrated in a short time, but kept silent. Arnbjorn and Ragnar said little during such revisions of their histories except once, when Arnbjorn said, "I'm sorry." After that, the tension eased a little.
As they neared their destination, it became harder and harder for Karl to fend off questions. "Yes, it's a comet," he admitted.
I've fired the last micro-probes at it, Loki said. Analysis indicates that it's ninety-seven point seven per cent water by mass, about as pure as we could reasonably have wished for. That should make our task easier. Then the download added, We're going to overshoot slightly.
"We need to strap in," Karl said, ignoring the continuing questions of the others.
"It's beautiful," Bera said. She leaned around, craning her neck to see out of the other windows. "Can we see the other worlds?" she said, and the wonder in her voice made Karl's heart turn over. He had Loki pull up a display on one of the monitors, and zoom in on Asagarth and its forty moons, the world itself halfhidden by the Bifrost asteroid belt.
"You never said it was so lovely," Bera whispered, her eyes misting up.
Karl shrugged. "I'm just too used to it most of the time, I guess."
When Loki applied the retros and they decelerated at three gees, it soon became apparent that Ragnar particularly would not stand up to two hours of triple gravity. "OK, we'll stay at two gees for as long as Ragnar can handle it."
Finally the Winter Song was travelling alongside the muddy ball of ice that was their destination, and Loki again spun the ship to generate a half standard gravity. It was, Karl guesstimated, no bigger than ten or fifteen kilometres across its main body, although its corona was streaming out for over two hundred and fifty kilometres, and a few wispy strands went even further – perhaps stretching for over four hundred kilometres.
The others looked at Karl expectantly. It was Arnbjorn who ended the silence. "So what's the plan, spaceman?" The title was accompanied by a smile.
Karl took a deep breath. "The Formers came about four hundred years ago, and left about two centuries ago." Karl had Loki replay the charts that the download had showed Karl. "CO2 has been building up much, much faster than the Formers planned. They may have decided to speed things up and reverse it when they came back – not intending to be gone so long; they may have thought that they could take a short-cut; or they may just have missed something." Karl suspected that there had been some kind of scam, or perhaps that Sigurdsson had hoped for someone to come along in the future with a solution, in the same way that terminal cases had been putting themselves into stasis for almost a millennia, waiting for a cure.
"But that's good, isn't it?" Arnbjorn said. "It'll warm the atmosphere, surely?"
"Some CO2 can be good, but not always," Karl said. "And something has happened that complicates matters enormously." He continued, "Loki has analysed trace composites in the Isheimuri atmosphere – from the exosphere, right down to the troposphere – that indicate that about a hundred and fifty years ago Isheimur passed through a vast molecular cloud." He gazed at Ragnar. "The vineyards that failed, that shouldn't have? The worsening weather, year on year, decade on decade?"
"Aye," Ragnar growled. "That was the dust cloud?"
"The first part was," Karl agreed. "The traces contain elements barely present in the Mizar quartet. Loki's sensors have just – barely – detected such a cloud way out toward Mizar B's Kuiper Belt. Anyway, the cloud is only part of the problem."
"I sense a 'but' coming," Arnbjorn said.
"Exactly," Karl said. "The 'but' is that the cloud didn't just block out some sunlight. Molecules in the cloud reacted with hydrogen in Mizar B's heliosphere – which extends way past Isheimur – and cascaded vast quantities of electrically charged cosmic rays into Isheimur's atmosphere, stripping away large parts of the ozone layer."
"Whatever the reason, it happened," Bera said, clearly growing bored with the lecture, or impatient for the conclusion.
"So much so," Karl said with a grin at his heckler, "that with some stripping away of the planet's ozone layer, the cloud is about to donate a nasty little leaving present."
"How so?" asked Orn.
If you'd let me speak, I'd bloody well tell you! Karl thought. He took a deep breath. "The magnetic field has just 'flipped' from warming to cooling, which will have catastrophic results."
"What can we do about it?" Ragnar asked.
"That's why we're here," Karl said. "We're going to steer the comet toward Isheimur, then, as we're approaching the planet, dump the ship's reactor into the comet, smashing it to fragments."
"You're what?"
"You'll kill everyone on the planet!"
"That's crazy!"
"How the fuck are we going to get home?"
Coeo was the only one not shouting, but he clearly understood from the others' reactions that there was something going on. Karl took another deep breath and translated into Kazakh.
Coeo seemed unimpressed. "Why should we care about the fake-furs?" he said. "We'll survive. We were made for the cold."
"Not for this cold," Karl said. "In this everyone dies – everyone and everything."
That is incorrect, Karl, Loki said. It's very likely that the adapted can survive.
But then he has no reason to help us, Karl sub-vocalised, and thought of Bera huddled, dying of cold.
"Then we must do it," Coeo said. "Though surely throwing down this icy spear will kill many, many people?"
"We'll keep deaths to a minimum," Karl said. "If we crash the core of the comet down onto the south polar ice-cap, we avoid everything but a few straggling rockeaters, as most of the adapted will have migrated northward."
"So this comet…?" Bera prompted. It was hardest of all to meet her gaze. The others had barged into his mission, but she'd accompanied him in good faith. Now that might be her death warrant, although if she survived, it would paradoxically be her salvation.
"We push it toward Isheimur, then dump the reactor and detonate it to break the comet up," Karl said, "and ride the biggest fragment all the way down, using emergency power to jump off when we hit the atmosphere."
"What?" Arnbjorn yelped.
"Are you scared?" Karl said, with a grin.
"No!"
"Then trust me – I have no desire to die, either," Karl said.
"What good does one comet do?" Orn said.
"It'll blast carbon dioxide and water vapour into the atmosphere," Karl said, "which will form a protective cloud and seed the ozone layer with water and debris, thereby raising the temperature and moisture. It's only a stop-gap, but it will buy another decade or two, while someone comes along, or until the magnetic field reverses again. Someone will come along to investigate," Karl said. "There's been enough chatter coming out of a supposedly deserted system to attract their attention." He hoped that he was right, but in all likelihood, he wouldn't be around to worry about it.
He explained it all to Coeo, who said, "But it will kill our people! They'll boil or suffocate!"
>
"No," Karl said. "It will only be temporary." Karl wished that he could be honest, could tell them about the harmonic tremors oscillating through Isheimur's lithosphere, but that would raise too many questions. "By breaking the comet up on the way down, we'll avoid the worst of the fall-out from one huge impact. Larger chunks will still fall to earth, but most will evaporate in the upper mesosphere, like handfuls of glittering dust thrown into the air."
"That's beautiful," Bera said. The others nodded.
Karl sub-vocalised, You have the flight trajectory? And you've calculated the point where we jettison the reactor?