We have travelled from one end of the heavens to the other and there is nowhere we can live.
Your purpose is not in the heavens. From the beginning they were closed to you. Tubal deceived you, bringing you here.
What shall we do?
In the end it will be revealed to you, when the time of Tubal is done.
Then I will know?
Then you will know.
I – MISSION PLAN
1. We were four months out when they told us.
It’s funny how you remember exactly where you were and what you were doing when really bad news arrives. I had left the crew in the Wardroom and was sitting in my recliner in the Rec room eating a plate of rehydrated asparagus. Domingo and Deiter had started arguing about religion again and after telling everyone that watching cartoons was likely to be more constructive I bailed out. It wasn’t like I was trying to make a point as mission commander or anything. Cloe and Tessa enjoyed the debates but I just wasn’t comfortable discussing the topic. After four months in a spaceship the size of a two storey apartment the secret of getting along with one’s fellow crewmembers is to not try too hard.
I had put Wall-E up on the screen but wasn’t paying much attention to it. About ten minutes into the movie a red dot flashed in the centre of the picture, accompanied by a musical dong dong that sounded through the ship, the signal for a message from Mission. I decided to play it before calling the crew. A lot of messages concerned only one crewmember who was a specialist in the subject matter.
I leaned forward with the remote and started the audiovisual message. Eugene Trinny’s face appeared on the screen. That made me sit up. The Director of NASA would not communicate with us unless he had something important to say. I noticed he was not smiling. A kind of cheerful bonhomie is de rigeur in earth-space communications unless something precise and technical is going on between Mission Control and the ship. Something was wrong.
“Hello everyone. I trust everything is fine with you. Seems from our end that Terra Nova is functioning normally.” The Director ran his fingers through his still-dark hair. “What I’m going to say may be difficult for you to take in. We’re still trying to take it in here.” He gestured to someone off-screen. An image appeared, a photograph of a small chunk of rock against a black background.
“1036 Ganymed. It’s the biggest of the Amor asteroids. It has an elliptical orbit with an aphelion well past Mars and a perihelion pretty close to Earth. Or it used to. We’ve been tracking it for the past two years since a planetesimal….next image...”—the chunk of rock was replaced by a starry sky with a red arrow pointing to a white dot near the centre—“since Deepstar IV detected a planetesimal coming into the solar system from the Kuiper Belt. It was probably hit by something else and deflected close to Neptune.
“Nobody paid much attention to it until its orbit was calculated. It was headed straight for Ganymed. At that point the information was given classified status until we had a better idea of the effect the planetesimal would have on the asteroid. Computer simulations predicted a change of orbit, with Earth within the hypothetical radius of the new orbital path. Right, back to the first image.” The chunk of rock reappeared.
“Impact between the planetesimal and Ganymed took place about a month after you left. We tracked Ganymed with all three Deepstar satellites until we had collected enough data to be certain. Ganymed will definitely collide with Earth fifteen months from now. About the time you’re due back.”
Everything froze for me except the image on the screen, a tiny, indistinct, innocuous pebble. Then it disappeared, replaced by the Director’s face.
“Let me give you the specs. Ganymed is about 31 kilometres long. It has a mass of 330 quadrillion tons. The experts tell me that’s pretty dense for an asteroid—about 3.5 tons per cubic metre, which is due to it having plenty of iron and magnesium silicates in its composition.
“The good news is that we have a plan for neutralising it. We can’t break it up but we’ll hit it with multiple nukes to deflect it. We have more than we need for the job so Earth will be fine. However you all have enough scientific and technical expertise to know there’s a degree of uncertainty in an undertaking of this nature, so we’ve devised a fall-back plan for you.” For the first time the hint of a smile appeared in his features.
“You’ll be getting new course settings. It won’t change your current path for the moment. You’ll still be going to Mars. If everything works out it would be a pity to abandon the whole mission just because of a scare. But we’re working on sending you a couple of additional supply ships. If necessary you’ll stay up there a bit longer than planned. To put it bluntly we’re turning the Terra Nova into a lifeboat.
“We don’t exactly know what the effects would be of a body this size hitting the earth. One has to factor in speed, mass, composition, angle of impact, all that. Our best models project that the Earth would remain habitable but would take a while to recover before you could return to it. The idea is to give you as much time as possible. Again, let me emphasize that this is just a precaution, a fall-back plan. Something that we don’t intend to use. Your primary mission should remain unchanged. We’ll fill you in as our information becomes clearer. Any questions you have we’ll be only too happy to answer.
“It was my recommendation when this came up not to hide anything from you. You can fulfil your secondary mission—in the remote possibility it becomes necessary—if you know exactly what’s going on. For now that’s all I have to say—except one thing. This information is strictly classified. No-one besides yourselves must know of the secondary mission. The last thing we need is any public impression that the situation is not entirely under control. I don’t have to emphasize how much we depend on your discretion. There’s a lot more at stake now. I’ll be available if you need to know anything further from me. Goodbye and good luck.” The screen went blank.
For a long time I sat still, not moving nor even thinking. Then I slowly stood up and walked quietly across to the door that led into the Wardroom where the crew were still at lunch. I stood out of sight beside the doorway and listened to the play between Dieter’s scepticism and Domingo’s uncertain earnestness.
“Good. So you say you can’t prove there is a God. Ja? Then why spoil your life for something that is a maybe?”
“I’m not spoiling my life. I’m here, on the first mission to Mars. If that’s a spoiled life then your life is spoiled too.”
“Ja ja ja. I mean, there is so much you can’t do, né? You walk down the street, you see a pretty girl, you want to get to know her better, but...the big man up there, he says no.”
Tessa’s voice butted in. “He doesn’t say no. I say no. He’d better not think of looking at anyone else while I’ve got a ring on my finger.”
“Wouldn’t dream of it, Tess, the ring cost a packet. Ow!”
“I’ve got him for life, so don’t try to corrupt him.”
“Oh ja, another thing you can’t do. Till death do you part. What a shame.”
“Don’t listen to him.” That was Cloe’s voice. “He doesn’t mean it. I am married to him for ten years. He is—how you say it—a stick-in-the-mud husband. He will never leave me, not if I beg him.”
A brief silence, then: “Ja, right. I keep what I know is good, but you will give up something for something else that you do not even know exists.”
“I said I can’t prove it, that doesn’t mean I don’t know...”
I entered the Wardroom. Cloe was the first to notice me.
“Who is it for?”
“For all of us.”
She frowned. My expression must have revealed something. “Is it bad news?”
“I think just come and see it.”
Bad news on a space mission usually means really bad news. The crew were silent as they filed into the Rec room. After a few moments everyone was seated in the semicircle of recliners arrayed around the large, metre-wide monitor that was the focal point of the Rec room. It was the one part of the ship that was designed to be comfortable, which meant you could stretch your feet out without bumping them against storage bags, cables, struts, restraining straps, wall equipment and anything else in the kaleidoscope of compact visual confusion that was the interior of the Terra Nova. When everyone was in place I replayed the message.
After it ended no-one spoke for a full minute. I could see the fear in my crew’s faces. Pull yourself together Jason. Get them back to some kind of normality. I stood up. “All right, we’ve heard the Director. For the present nothing changes for us. We carry on as usual and work on the assumption that Earth will deal with this situation. All agreed?”
Tessa nodded, trusting as usual. Cloe’s expression was impassive as if digesting a technical report. Domingo looked at me and gave a thumbs up. Dieter continued staring ahead, preoccupied.
“Dieter?”
He glanced at me. “Ja, Jason. Carry on as usual.” His eyes drifted away again. I wanted to speak to him but decided against it. Right now we all needed time to adjust. Too soon to talk about it, especially as the information was so sparse. That gave me an idea.
“Any questions you have about this write down or record. When everyone’s given me what they have I’ll send it to Earth in a single transmission. When we get more information we’ll have a better idea of what to expect. We might even come up with some ideas ourselves.”
“What can we have to say about it?” Domingo interjected. “You’re a general-purpose astronaut. Cloe is a physicist and geologist. Tessa is a biologist. I’m just the damned pilot. Only one who has some kind of expertise in this is Dieter. But engineering doesn’t cover all of it.”
“Too big,” Dieter murmured.
“What’s that?”
“It is too big. Nuclear warheads will do nothing to it.”
For the first time I felt something: a kind of freezing sickness in my stomach and throat. Not because of what Dieter said but because up until then I had refused to think about it, letting Trinny’s assurances cocoon me. But if Trinny was so sure Earth could deflect the asteroid then why the lifeboat plan? The silence lengthened. Dammit, back to normality.
“We don’t know that. And they don’t have to destroy it, just knock it off course.”
Dieter’s eyes rose up to me. “An asteroid thirty kilometres in diameter?”
Tessa spoke up: “If they use the velocity to increase the explosive effect...”
Dieter shook his head in irritation. “Velocity does not matter. A nuclear bomb emits radiation only. No shock waves. And radiation travels at the speed of light no matter how fast or slowly the bombs move.”
Domingo turned to him. “If they can get them to it early enough that should do the trick. The asteroid just needs a slight shift. If it’s beyond the orbit of Mars, say, the deflection only has to be fractional.” The crew was gradually coming out of their shock.
Dieter tapped a finger on his armrest. “How soon can they fit warheads into long range launchers? Have you thought of that? The conversion? That is weeks, months of work. And what about the flight path? A straight trajectory out will need a big amount of fuel. That means a smaller payload. There is no time to take an indirect path around Venus to save fuel like we did. But where is this asteroid?”
“That’s your first question,” I said, “start making a list.” I paused and smiled. “And don’t think we can’t bring anything to the party. We all have a lot of knowledge in fields outside our mission competence.”
“Yeah I know,” said Domingo. “If Sumerian culture has something useful then you’re the man to ask.”
“You hacked my tablet?”
“Nah. Just glanced over your shoulder once or twice.”
I shrugged. “My point stands. Problem-solving isn’t about having a PhD. It’s about having enough facts to be able to think outside the box and come up with a solution. Let’s see what we can do.”
By the time the impromptu meeting broke up we were nearly back to normal, well, as normal as could be expected given the circumstances. Our initial fear was gone, or rather it had mutated into something more subtle, something I did not immediately put my finger on. It was not the simple fact of the news, nor the possible effect it would have on our original mission. It was something deeper, a strange feeling of isolation, of no longer being carried along by a vast carefully-rehearsed adventure, a heavily-documented exploratory foray in which everything had been planned to the last detail, with virtually nothing left to personal initiative. We were to be mankind’s first manned outreach to a neighbouring planet, and everything we did we did with that realisation. Our movements to be filmed, our words recorded, our feelings—well, the feelings we deemed proper to air in public—to be analysed, our return to be fêted.
And now, quietly and unobtrusively, like the dipping of the sun below the horizon, it was gone. We were in a steel tube, tens of millions of kilometres away from a home that lay in the shadow of obliteration. On every level of human motivation, except the basic instinct for survival, our journey had become meaningless. And pure survival is bad for the human psyche.
The only private place in Terra Nova is the bunkroom. Each crewmember had one, a reluctant concession by the ship’s designers who recognized that every astronaut’s desire for private space would become too important to ignore on a two-year mission. Marital status made no difference.
Hygiene is one aspect of space travel that receives little publicity. The simple fact is that there is not enough water on a space ship—even one the size of Terra Nova—to keep oneself properly clean. A shower, though possible, is a rare treat. Most of the time a spacer is limited to sponging himself down with a moist pad. Brushing of teeth was done with toothpaste and very little rinsing water.
In consequence experienced spacers tend to keep a respectable distance from each other. Things are not so bad in the open areas of the ship where fans keep the air in constant circulation, but in the closed confines of a bunkroom the most solid of marriage bonds would be tested to the limits. So, one bunkroom each.
The bunks themselves were two-tiered, on either side of which were a stateroom with a fold-down desk and chair, with brackets on the walls for personal items. The walls, like all non-walking surfaces of the ship, were padded to prevent injuries when moving around during periods of weightlessness.
Each bunk formed a separate room, and one was not directly accessible from the other. It was a compact, practical arrangement and I made full use of it. One thing you have plenty of during a deep space mission is time. Astronauts on the ISS2 were kept busy with dozens of scientific experiments that should have been done by specialists and could have been done better by automated instruments. Space travel is all about politics. There is really no good reason for keeping humans in low Earth orbit for months at a stretch, other than to show that space is not a closed frontier and the taxpayer can carry on being optimistic about the future. Governments pay billions for that optimism.
On the Terra Nova, however, we did not have a hundred redundant tasks to perform. Mars was reason enough for our eleven month journey. In the narrow confines of a spaceship a regimen is necessary to maintain physical and mental equilibrium, but that still left several hours a day on hand. I used mine for reading. My tablet held about eight thousand books, with any number more accessible from the ship’s onboard library or by request from Earth. Right now, though, I preferred to lie on my bunk and do some thinking.
My big weakness is that I’m a bad psychologist. Psychological intuition is not a necessary trait for a commander. My job was to keep intact the invisible thread of mild authority that was wrapped around the crew to hold them to their purpose, and make all the difficult decisions should an emergency arise. I was not expected to act as their shrink. That had been done years earlier by therapists who ensured that anyone in the slightest need of therapy was excluded from the mission.
But this was a new scenario, not envisaged by the selection programme, and I would have to try and weigh up its effect on each of us.
Tessa did not worry me. With disconcertingly dark eyes that belied her boyish looks, she was the true idealist of our group, capable of seeing space travel as a grand and noble endeavour. It was something that still surprised me even after four years of knowing her. She was not a profound thinker and built her peace of mind on her work and on Domingo. So long as both were there she would be fine. It was a pleasant thought as she had a sunny and social disposition that went a long way towards bonding our group together.
Cloe, too, did not cause me concern. A small woman, pretty in the Languedoc French way, whose tight, spare frame was the perfect home for a temperament that can best be described as professional, she was a steady and competent, working well as part of a team, even though she had a quieter temperament than Tessa. Under that placidity there were depths, good depths, capable of rising to the occasion when necessary. She would cope.
So would Domingo. His was the most easygoing personality on the ship, possessed of an optimistic outlook that held, I felt, a capacity for courage if the need arose. He was a Hispanic with a distinctive shock of dishevelled black hair and a Catholic upbringing to which he still adhered though some of his beliefs were perhaps a little hazy. But he was solid.
Dieter was the most competent crewmember on the mission, whose stocky build and handsome face housed a quick, sharp, problem-solving mind. In simulated emergency situations he performed best and invariably found the correct solutions first. But how would he cope when there was no solution, no neat answer that left us and the ship intact? This I did not know. He was agnostic like Cloe, but with a pragmatist outlook. How far did his pragmatism go? I shook my head. It didn’t matter. We were all in it together. Whatever happened, we would have to cover one another’s backs to survive. I could depend on Dieter.
That left one last crewmember—me. We were reasonably certain of surviving the next fifteen months. There was a good possibility we would survive a year or more after that if supply ships were indeed sent to us. After that we were sure of nothing. Neither of being able to land on a planet devastated by a thirty kilometre-wide asteroid, nor of being able to live on that planet even if we managed to make it to the ground. What would we find? Seas of molten lava or a perpetual arctic winter? How anarchical would human society be on our return?
It had been there from the moment of Trinny’s announcement, but I could only fully acknowledge it now: my background fear wasn’t going away. Our sense of security comes from the perception that not only the present but also the future is safe. That was now gone and I had no idea how its loss would affect me in the months to come. I would have to watch myself as much as the others.
2. Mars was seven months away and during that time I thought about it only occasionally. By the time our first transmission was ready we had over three hundred questions, most of them concerned with the path, mass and speed of the approaching asteroid. The answers absorbed pretty much all our attention. The trivial question of whether we would complete our original purpose and make a landing on Mars was shrugged off as something we would think about only on actual arrival.
We already knew that the asteroid’s trajectory was close to our return path from Mars to Earth, but now we learnt just how close. If we followed the original mission timetable we would almost graze it on the last leg of its journey towards the Earth. NASA’s plan was for us to stay in Martian orbit for another two years until the line-up between Earth and Mars was again suitable for a return journey.
One plan was considered and quickly abandoned: to complete our return journey as per the original schedule and go into orbit around the moon until conditions on Earth were stable enough for a re-entry. It was deemed too risky. Debris from the asteroid impact would reach as far as the moon and further. The Terra Nova stood a good chance of being pulverised whilst in lunar orbit.
The supply ships had been readied and would soon be launched. Terra Nova had been designed to be as self-sustaining as possible. Water was carefully conserved and recycled. Oxygen was manufactured from our carbon dioxide. Energy was not a problem: our solar panels would keep the life support systems going indefinitely, and the ship’s nuclear thermal rocket had enough hydrogen for the new and slightly longer return trip. The only non-renewable commodity we depended on was food, and the next broadcast from Mission Control outlined the nature and severity of the food rationing regime we would now have to follow. We would be hungry, and we would get thinner, but our stocks and the fresh supplies sent to us would be enough for an extra two years. We would survive.
In the case of Earth things were less clear. Any attempt to destroy the asteroid was ruled out early on. It was just too big, and even if one could bury nuclear charges deep under its surface and detonate them, as some theorists suggested, the resulting fragments, impacting over a larger area, would cause even more damage than that inflicted by the intact asteroid. Deflection was the only option and here the maths became blurry. Ganymed was set to hit the Earth square on, almost in the middle of the bull’s eye, hence a considerable force would be required to nudge it far enough for a miss.
Nukes launched from Earth would not reach Ganymed much before it crossed Mars’ orbit. It would be necessary to slow the asteroid down by at least 30cm/s. 30cm/s doesn’t seem much, however for an object as huge as Ganymed that would require a nuclear punch equivalent to 80 000 megatons of TNT. The largest bomb ever built was the Tsar Bomba, detonated by the USSR in 1961. Its theoretical maximum yield of 100 megatons was reduced to 50 megatons so as not to destroy the plane that dropped it.
The largest current bomb was the 10 megaton Chinese Quántóu, built a few years earlier as relations frosted between China and Russia, but there were only a handful of them. However as the threat of Ganymed became evident the nuclear powers were forced to co-operate and take the red tape off their classified files. Russia had built bombs equivalent to the Tsar, lots of them, and so had China. Their military policy, hitherto secret, had been a reversion to the 20th century Cold War strategy of vaporising your enemy, relying on countermeasures to stop him vaporising you. About 600 Tsar-grade bombs could be readied at short notice, along with hundreds of smaller yield ones, enough when combined to give the asteroid the necessary push.
The next problem was getting them to Ganymed. A Tsar bomb weighed 27 tons, well beyond the capacity of a Eurostar Heavy which could transport a load of no more than 13.6 tons to Mars. I thought wistfully of the Starship and its 100-ton carrying capacity, long since buried with a bankrupted SpaceX. There was however another way of getting the massive bombs into orbit—Skylon spaceplanes. A Skylon 4 could lift a load of 30 tons into low Earth orbit. More importantly, it could land and do it again in a couple of days. It could lift not only the bombs but also the boosters and fuel necessary to get them to Ganymed.
There were about two dozen Skylon 4s in service. Working round the clock, they could get enough atomic power into orbit and on its way in time to deflect Ganymed. That is, there was a good chance they could. Custom-made boosters along with their guidance and detonation mechanisms would have to be designed and built in a hurry, with little or no time for testing. To offset the probability of failure of at least some of the nukes, Earth would have to send as many as possible.
In the end, the plan was to dispatch nuclear warheads successively to the asteroid as soon as they were ready. The Ganymed team, as the original discoverers of the planetesimal that hit the asteroid were now designated, concluded that the combined effect should be enough to move it clear of the Earth, but they could not be sure. 94% success probability was their most hopeful estimate. We did not realise just then what that meant.
“Why only ninety-four percent?” asked Domingo after the AV transmission was ended. “Isn’t it just a question of calculating the explosive pressure of an atomic bomb versus the inertia of the asteroid. Heck, I can do that.”
“I have already done it,” said Dieter. “Theoretically we have more than enough bombs. We need the equivalent of eight hundred bombs of one hundred megatons each. But most of them must get to the asteroid before it intersects Mars’ orbit, which means they must launch them soon. That is where it becomes uncertain. When can they get the boosters ready?”
“And there is another problem,” said Cloe.
Dieter nodded. “Ja. Its composition. We don’t know how densely bonded the material of Ganymed is. If it is a loose rubble pile then there is a chance the bombs will make it disintegrate rather than deflect it. The fragments will scatter, some will reach the Earth. This could cause more damage than if the asteroid hits the Earth intact.
“That means a standoff explosion. The bombs must detonate at a distance from the asteroid—enough so the radiation saturates its surface evenly on the one side. The heat will cause the regolith to expand explosively and the reactive force will propel the asteroid in the opposite direction. The further away the blast the more uniform and widespread the pressure, but also the effect is weaker. It is...how you say...a trade-off.”
“What about several bombs near the surface detonating at the same time?” Domingo suggested.
Dieter shook his lead. “That is difficult. The warheads must be in exactly the right place and detonate absolutely at the same time. Otherwise one that explodes first may knock out the timers of the others. They may not work.”
“NASA’s plan makes sense,” I said. “Successive warheads detonating one after the other with just enough time between them to prevent each from being damaged by the one before it.”
Dieter drummed his fingers on his recliner’s armrest. “It is a pity they cannot space them further apart.”
“Why?” asked Cloe.
“To give time to calculate the effects of each blast before they commit the next warhead.” His voice dropped as if speaking to himself. “So much can go wrong.”
“Is he always this pessimistic?” asked Tessa.
“It’s his job,” Domingo replied. “He has to look for holes in doughnuts and fill them up.”
Tessa shrugged. “A doughnut that’s ninety-four percent doughnut. I can live with that.”
Dieter smiled. “I am not so fond of doughnuts.”
“Yeah,” grinned Domingo. “He’s into Berliners.”
“What’s a Berliner?”
“A German doughnut without a hole.”
Artificial gravity—imperative for a crew that spent more than a year and a half in space—was achieved by the simple expedient of tumbling the long, rod-like Terra Nova end over end, with the angle of rotation set at 90 degrees to its forward movement to permit the communication dish, fixed in the middle of the ship, to always point towards Earth. The living quarters, at one extremity of the ship, felt the full effects of centrifugal inertia, creating a gravity at 60% of Earth’s, sufficient to offset the worst problems of prolonged weightlessness.
When watching the classic space movies of the last half century I was always amused by the scenes of vast, sleek ships sliding smoothly forward through space. The truth was less stylish. A manned deep space vessel was more like a huge tomahawk thrown wrong. Space travel is not artistic. A ship, however, cannot make flight adjustments whilst spinning upon itself. As we entered the second week of November 2047 the red planet became a bright crimson star visible from the Wardroom’s side window. It was time to decide what to do about it.
Two months before we left Earth, three unmanned ships, the Shirase, Atlantis and Shepard, had been assembled in Earth orbit and sent ahead of us to Mars. Shepard carried the Mars Lander, to be used to reach the Martian surface and get back into space again. Atlantis held the Mars Surface Habitat, or Hab, the living quarters for our projected two-month stay on the planet. Shirase was a power plant and supply ship that also transported the rovers we would use to travel over the Martian desert. With the exception of the supplies on Shirase, they could not be cannibalised for the Terra Nova. We did not have the tools and, more importantly, the know-how. They would have to be used as originally designed or abandoned.
“Then we abandon them,” said Dieter. “Why the risk of a landing when there is no point? Who cares about our mission now?”
We were all seated round the table in the middle of the Wardroom having breakfast. Like everywhere else on the Terra Nova, the Wardroom was compact. From either of the two long sides of the table you could push your chair out slightly, lean back and rest against the rectangular storage bags that formed the wall. NASA had not yet made up its mind on the subject of a Marsfall. Adding any further risk to the lives of a crew that already faced far greater risks than originally envisaged had to be weighed against the immense fiasco of an aborted mission in the likely event of Earth coming through safe and sound. I popped another dried fruit in my mouth and did what a good commander does in these circumstances. I listened.
“There is a point,” said Cloe. “The risk of a landing, it is not much greater than staying up here. Why come all this way and not finish what we came to do? What difference can it make?”
Dieter’s eyes flickered across to her. “It can make a big difference. Atmospheric entry is always dangerous, especially on Mars, you know this. An atmosphere thick enough to need a heat shield but too thin to slow us down so we can parachute in for a landing. We need a shield, a hypercone, a parachute, and retro-rockets, all timed exactly”—he put his thumb and forefinger together—“split second. It is complicated, balanced on a razor. If anything goes wrong we are finished.”
“But we came for this. We trained for it. We know the risks.”
“I know them too. I am not worried about the risks in themselves. They were always a part of the mission. You live with them, you work with them when you must.” He leaned back in his chair. “Our priorities are different now. As I see it our mission has changed.” He brought his finger down on the table. “There is a six percent chance that Earth will be hit, ja? and it will become unapproachable. We will have to spend two years in space that were not in the original planning. We cannot afford to take more risks than necessary.”
Domingo, like me, had been listening as he worked through his ration of scrambled egg. “That isn’t what Mission said,” he interjected. “We have to do both jobs. They haven’t changed the orders yet.”
“We can do both,” said Tessa. “Mars landings have been done often enough. It’s not as if we’re new at it. None have gone wrong for the past twenty years.”
“What’s the problem anyway?” said Domingo. “The biggest single risk on the mission is the Mars landing. Spending another two years in space is no big deal. We were all cool about landing before. Why not now?”
Dieter leaned forward. “The success rate is still only 45 percent, and that is for unmanned landers. This is the first manned landing. But there is something else you have not considered.” He glanced at me.
“What’s that?”
“What will happen to the Earth after impact?”
I frowned. “What do you mean?”
“I mean who will be alive afterwards?”
“We know there would be horrific casualties, but a large portion of humanity would survive.”
“Are you certain of that?”
“Why shouldn’t I be?”
“Because that is a projection. A hypothesis. The effect of an asteroid thirty kilometres wide hitting Earth has never been analysed in depth. We do not know for certain what will happen. The impact winter could kill all life on the surface. If the ejecta in the atmosphere is thick enough it could drop temperatures to 100 below zero, 150 below zero, more. Who knows? That can last a year, perhaps longer. When we return we may be the only humans alive.”
Dieter paused to gauge the effect of his words. He wasn’t disappointed. A heavy silence hung in the room.
“Trinny called the Terra Nova a lifeboat. I think there is a good chance it may become an ark.” He spread his hands. “We may be all that is left of the human race.”
Tessa shrugged “Then that’s too bad for the human race.” She looked around at our surprised faces and turned red. “I mean...if we’re all that’s left of the gene pool it’s going to be kinda rough on our descendants.”
Domingo grinned. “I think you got fabulous genes.” He glanced at Dieter with an odd expression that I could almost have taken for hostility.
“In any case this is all speculation,” I said.
“Ja, I am speculating. Trinny is speculating too. We do not know for certain what will happen. If we do not know we must assume the worst. Our duty, now, is to survive.”
The problem was that I could not fault his logic. A Mars landing was a secondary priority, to be balanced against our first which was simply to stay alive. But I was tired of mental cowering. In this time of peril for humanity I wanted to take chances, defy the fates, do the job we were made for.
I finally spoke up. “Domingo’s right. It depends on Mission. They call the shots for a big decision like this.”
The irritation showed in Dieter’s voice. “Well, when do they make up their minds?”
“Soon enough. For now we keep on schedule. We take off the centrifugal spin and do an orbital insertion burn in twenty-eight days’ time. Whatever happens we’ll be hanging around Mars for a while.” When in doubt do nothing. A piece of advice from my old air force commander that had stood me in good stead more than once. It was the right decision, but as I jogged on the treadmill an hour later in the packed confines of the upper equipment bay it bothered me that I had had to make it. The subject of a landing should have been settled weeks ago. NASA could have determined right away whether it was worth the risk or not. Why the delay? Seen in the cool light of a Houston boardroom Dieter’s reasoning was watertight, and for the last month I had been expecting an order to abort the mission. I raised the subject once in an eyes-only transmission for Eugene Trinny. The reply was a voice message and I listened to it with earphones.
“Trinny here. I know you’ve been wondering about why we don’t give a definitive green light on Mars. You’ll get our decision in good time, don’t worry. We’re still working out whether it’s worthwhile for you to go down or not. Sorry I can’t give you more information at this point, but we’ll keep you posted. Let me know how the crew are coping. Trinny out.”
Brief and clinical. What was he not telling me?
It was Dieter who noticed our problem. The three unmanned ships that had gone ahead of us had performed an aerocapture manoeuvre to reduce their speed, passing 50 km above the surface and letting the atmosphere drag slow them enough to drop into orbit around Mars. For the Terra Nova this had been deemed too dangerous. During aerocapture the surface of a spacecraft heats up drastically, making a heat shield necessary, whilst the vessel’s structure is put under tremendous strain by the irregular buffeting of the air. The Terra Nova was just too big and fragile for that. We were to settle into a low orbit of about 400km above the surface by a single burn, using up a large percentage of our fuel but obviating the uncertainties of a low pass through the atmosphere.
The point though is that things had changed. We were no longer in a hurry, and we needed to be misers with every resource we had. We were still three weeks away from orbital insertion burn. I was lying on my bunk taking a little shuteye when a brief knock at my stateroom doorway stirred me to consciousness. I opened my eyes. It was Dieter.
“I wake you up?”
“Just dozing. What’s the problem?”
“It makes no sense.”
“What doesn’t?”
“The return trajectory. If we do not go back in three months as planned the only chance we will have is two years later.”
“We know that. So?”
“We cannot wait two years.”
I looked at him. “Why not?”
“The thermal fuel rods. Their half-life is too short. They were designed for a two-year mission. If you add another two years on top of that they will have degraded so much they will not supply enough heat for the hydrogen. We will be underpowered.”
The Terra Nova’s main drive was a nuclear thermal rocket. Liquid hydrogen is run through a drive chamber containing plutonium 238 rods, which heat it to about 2800 degrees centigrade. The superheated hydrogen expands violently and is ejected through a nozzle, supplying the thrust. Since there is no need for oxygen to get the hydrogen to combust, the fuel load is half that of a conventional rocket. Plutonium is used in preference to Uranium as it won’t melt in the high temperatures and requires minimal shielding for the crew, but its half-life is only about 88 years.
“That’s four years out of eighty-eight.” I said. “Will it make that much difference?”
“Ja, it will. The lineup in two years’ time is not ideal. We need the motor at full capacity to be sure of making it. We will not once you factor in the decay.”
I gazed up at the ceiling. NASA would have figured this out long before we did. What was going on?
“OK,” I said, getting up. “Council of war.”
The natural place for crew discussions is the Wardroom. Once we were all seated around the Wardroom table I let Dieter give the news.
“We can dump everything superfluous,” said Domingo. “Samples, scientific equipment, anything like that. That should be enough...”
Dieter cut in. “Not enough. We lose very little weight that way. There will be a big shortfall of power. We will need to remove the living quarters and the crew to make enough of a difference.”
Cloe looked over at me. “Mission—does it know about this?”
“They haven’t mentioned it” I replied. “There’s a possibility they overlooked it.” Cloe glanced at Dieter then looked away. “We’ll have to let them know now,” I continued. “They may have a contingency plan.”
Domingo gave a snort. “What plan, short of sending us strap-on boosters?”
I shrugged. “It’s possible they have just that in mind.”
“Is there anything else we can do?” asked Tessa. “The supply ships have engines. Can’t we tie them to the Terra Nova and use them for the additional thrust?”
“We do not have the tools,” said Dieter. “How do I weld in space? No arc welder. And Terra Nova is not designed for that kind of structural stress. It is impossible to say what will happen. I cannot do it.”
“I thought you were the fixit man.” said Domingo.
“That does not make me a magician.”
“No way of doing a fuel transfer?”
Dieter stared at him. “Liquid hydrogen? Are you mad? The pump, the transfer pipes, where do they come from?”
“Easy man, just checking the options.”
I put my hands on the table. “It looks like NASA will have to find the solution for us.”
“There is a solution,” said Dieter.
“And what’s that?” I asked.
“We aerobrake.”
I opened my mouth to reply then paused. A relatively short burn would put the Terra Nova into a steep elliptical orbit around Mars. Aerobraking was a way of turning that into a near-circular orbit. It was safer than aerocapture and did not need a heat shield, but it was time consuming.
“We drop to a hundred kilometres above the surface,” Dieter continued, “That puts us in the upper ionosphere. Enough to brake us a little but we do not get too hot.”
“How hot?” asked Domingo.
“One hundred and seventy degrees centigrade.”
Tessa shook her head. “That’s still hot.”
“The ship can take it,” said Dieter.
I drummed my fingers. “The solar panels?”
“We fold them.”
“OK,” said Domingo. “How long will it take?”
Dieter pushed a pad he had brought with him to the centre of the table and took a pen from his pocket.
“We do a burn just long enough to be captured by Mars...a long elliptical orbit like this, ja? After a day and a half we enter the ionosphere for a little then back into space. 36 hours later we complete the orbit and pass through it again, but now the orbit is a little shorter - so. Eventually we slow down to a circular orbit like this.”
“How long?” Domingo asked.
“Six months. We save a lot of hydrogen. When we return to Earth the hydrogen will not be heated so much but there will be more of it. We will have more overall thrust. Enough for a return trip in two years. I have done the calculations.”
“We don’t have six months’ extra supplies,” I said.
“We will have them. We have eight months’ provisions. If we aerobrake we will still have two months’ left by the time the supply ships arrive. And we will have twice as much fuel.”
“What about the mission?”
“We can still land on the surface once we have matched our orbit to Atlantis. We just put the timetable forward six months. We are here for two years anyway.”
“Yeah, makes sense,” conceded Domingo.
“Ja, it made sense to me a week ago.”
“Why’d you only bring it up now?” I asked.
“I needed to make sure first—I ran simulations to see what the margins are.”
I looked around. “Anyone got any objections?”
Domingo shrugged. “Hell of a piloting job. We’ll have to take shifts.”
Tessa smiled. “It’ll be fun.”
Only Cloe was silent. So far she hadn’t spoken or done anything except run her finger over the table surface.
“Cloe?”
She looked up. “You must confirm this with Mission.”
“Of course.”
“I think you must tell them soon.”
“Sure, Cloe. I’ll transmit after this meeting. We need to start the calculations right away.”
She nodded. “We need their clearance. We also need to know what our timeframe is, when the supply ships reach Mars, their orbital path, their ease of access, all that.”
“Goes without saying.” Tessa and Domingo pushed their chairs back. The meeting was breaking up. Only Dieter seemed preoccupied. Cloe got to her feet and gave him a glance before quitting the table. I noted all this without realising its significance until later. The trouble when dealing with people in a hands-on fashion, especially in an abnormal situation, is that it distracts one from taking the long view and seeing the obvious. I would have time to regret that later.
Eyes only. Commander Jason Montague to Director Eugene Trinny Please advise on a suggested change of flight plan from a full orbital insertion burn to a partial burn resulting in an elliptical orbit, with multiple atmospheric passes to aerobrake into circular orbit. The resultant saving on hydrogen will compensate for the degradation of the plutonium fuel rods in two years’ time when a return journey from Mars to Earth becomes possible. Advise on arrival time of supply ships with full details of orbital path and height and all additional relevant information. Please reply immediate, to permit calculations for altered burn time and orientation.
Eyes only Director Eugene Trinny to Commander Jason Montague Negative on request for change from orbital insertion burn to partial burn with aerobraking. Proceed as per normal schedule with full orbital insertion burn into circular orbit. We are aware of plutonium degradation problem and will address it at the appropriate time. Details re supply ships will be communicated nearer arrival time. Still six months away, what’s the hurry? Advise crew that a landing on Mars will proceed as per original schedule. Necessary at this point to keep morale up on Earth. Seeing NASA doing business as usual will help convince everyone we have the Ganymed problem licked. Good luck. Director Eugene Trinny
I read the reply on my tablet several times over in the privacy of my bunkroom. It was a strange mix of informal banter and bureaucratic opacity. The more I tried reading between the lines the more puzzling it became. My orders were clear but they made no sense. There was no answer to our fuel problem short of strapping on boosters as Domingo had sarcastically suggested, and I could not imagine how they could be custom designed, built and sent to us in time. No, Dieter’s solution was the only viable one if we were to extend our stay in space. I switched on the holographic keyboard and typed my reply:
Eyes only. Commander Jason Montague to Director Eugene Trinny Please advise on nature of solution to plutonium decay problem. Dieter adamant he cannot refuel the hydrogen tanks. Only viable suggestion is supplementary boosters. Confirm if this is possible.
Eyes only Director Eugene Trinny to Commander Jason Montague Confirm supplementary boosters will be sent. Construction nearly complete. Will advise on practical details after Mars landing. Big moment coming. Make sure your first words on Mars are good.
I no longer had a sense of puzzlement. It was gone, replaced by a growing sense of unease. I read and reread the words until I knew them by heart, then switched off the tablet. Inserting it into its wall jacket I lay back and put my hands behind my head, deep in thought.
The bond of trust between people is built on an absolute reliance on others when something serious is at stake. It is in trivial matters that we let each other down and still get along. NASA is a particularly close-knit community, made up of competent professionals whose job is to keep people alive in space. Trust is a given. As commander my particular responsibility was my crew’s survival. It was a responsibility that was accepted and passed up. I trusted NASA absolutely. And now...
I needed some fresh air, which meant I needed to get out, at least out of this tiny and constrictive cubicle of a room. I made for the floor hatch that opened on wall rungs leading down to the level below. I wanted to look out the porthole in the Wardroom at least, if I could not go for the good, long walk that was mandatory back on Earth for moments like this. On arrival I found the Wardroom occupied. Cloe was busy preparing our next meal at the galley. I wandered over to the round porthole above to the Wardroom table and looked out. With the glare of the room lights there wasn’t much to see, just a couple of stars. I turned around. There was no-else on that level.
“Where are the others?”
Cloe’s back was turned to me. “Dieter and Domingo are checking the airlock on the PriFly deck. Tessa is in the upper equipment bay.”
“I need to talk to you,” I said.
“Go ahead.”
I pulled out the nearest chair and sat down. “Why did you ask me about a green light from Mission before we try aerobraking?”
“We need it before we can do anything.”
“I know that. You know it. We all know it. Point is why did you bring it up?”
She paused in the act of emptying a full sachet of water into an aluminium pot.
“What do you think their answer was?” I asked.
“No.”
“And how did you know that?”
She resumed emptying the sachet. “Because this lifeboat story is rubbish. They have no solution to the fuel problem but it is no matter. We do not go back in two years’ time. We do not get any supply ships.”
“How do you know?”
She sealed off the sachet tube and placed it on the galley board. Then she turned around and looked at me. “Merde, Jason, sometimes you really are stupid. You can’t work it out?”
“Maybe I need some help here.”
“The asteroid. The moment they realised they maybe did not have enough bombs we became second priority. The supply launchers are taking bombs to the asteroid.”
Dammit but she was right.
“Then why did Trinny give us the lifeboat scenario in the first place?”
“No idea. Maybe they thought they could not hide the impact story from us so they have to give us something to keep us going. We can sometimes pick up signals from other sources besides Mission. Maybe in the beginning they thought they could spare us a launcher. Who can know? The important thing is we do not get any supplies. We go back in three months and hope the asteroid misses or we stay here and die.”
I said nothing for a full minute, chin on fist. Then I looked up at her.
“All right. I’m not happy Mission hid the truth from us but I have to accept they did it for a good reason. I don’t know…we can’t be sure the effect it would have on the crew.”
“Jason, we can cope.”
“You can maybe but can you be sure about the others?”
“I still think you should tell them.”
“I tell them and it’s tantamount to a vote of no-confidence in NASA, and we can’t function without Mission. Cloe I don’t have a choice. I can’t have a paranoid crew. Have you told anyone?”
She paused a moment. “No.”
“Then don’t. I want you to keep this between ourselves.”