To Be Taught, if Fortunate
Page 12
I did not feel joy in this simplicity, as I did on Aecor. I don’t know what to call the feeling. ‘Emptiness’ sounds depressing, ‘stillness’ dull. I think that Votum is like the mirror in my cabin. It doesn’t presume anything, doesn’t force any decisions. It doesn’t angle itself toward me. It just lets me think. I respect it deeply for this.
After each walk, I’d return to the Merian coated with a fine layer of red dust, clinging to my suit like a second skin. I loved watching it dance around me in the airlock as the fans brushed it loose. The particles formed murmurations, which gently twisted toward the vents as they were shooed back outside. Every time, as I watched the dirt disappear, as the sterilising plasma wreathed me in swirls of airy purple, I stepped back into my craft feeling a little bit lighter than I had the time before. I know it was only my suit that was cleaned, but something nameless – something that had originated within me – was scattered to the wind along with the dust. Whatever it was, I did not need it back.
Chikondi burst into the cabin, waking both me and Elena. ‘Cubesats,’ he gasped. He started to say something else, but gave up, frantically gesturing at us. ‘Water,’ he managed.
We threw on clothes and ran.
Jack was in the data lab, furiously entering commands into the console. ‘It’s coming in now,’ he said.
‘What’s coming in?’ Elena said.
An image spread across the screen: Votum from above, a parched rockface with the occasional accent of airy cloud. I’d seen this patch we were looking at before, a series of canyons the team back home had nicknamed the Furrows. The telescopes in Earth’s orbit hadn’t been able to see what lay inside them, but we could. The grand majority of them were empty – geologic wrinkles, nothing more. But in one, way down deep in the shadows, there lay something promising. A reflective sliver. A filament a casual glance would miss entirely.
We held our breath.
An enormous smile spread across Jack’s face. ‘Told you,’ he whispered.
‘This looks like a good landing site,’ I said, pointing at a plateau near the canyons. ‘I know we just got the lab set up, but—’
Chikondi started gathering everything that wasn’t bolted down: styluses, water bottles, someone’s jacket. The message was received. We were packing up, and we were doing it now.
We launched, and landed.
We set up camp, again.
We left the Merian at dawn the next day, and hiked some four kilometres out.
We rappelled down the ancient walls into the shaded dark. The canyon wind whistled past, greeting us ghostily.
We walked for a time, our footsteps echoing in all directions. Had there been such echoes in this canyon before? I wondered. Was the air here accustomed to carrying sounds beyond those it created on its own?
We rounded a corner, and there it was: one thin river – a creek, really, if we’re being accurate. It was not in any particular hurry, and would barely have reached my knees if I’d stepped into it. Its surface glinted a mercurial grey in the light of our headlamps. Its meandering pace created a pleasant chatter along the stones it had worn smooth. The irony did not escape me – I’d ached for respite from the aquatic clamour on Opera, yet here, the sound of water was the most welcome thing imaginable.
There was something missing, though, and I could feel our collective mood dip just a touch as we individually registered it. The river had no plants, no moss, no encouraging stripes of scum. Nothing swam beneath its ripples or tiptoed toward the bank in search of a drink. Perhaps the number of living organisms on Votum numbered just four, I thought, and only temporary residents at that.
Chikondi opened his toolkit and knelt down beside the river. He retrieved a field microscope. He dipped it into the water.
We crowded patiently behind him.
The little viewscreen switched on, and the image projected was white, pure white, the same colour as the base of the sample chamber. Chikondi gently rocked the microscope, encouraging other bits of the sample to slide into view. We saw a lump of rock, a shred of silt. That was all right. Finding nothing was all right. There was still so much to learn, even in the absence of—
Out of the bottom left corner, a shape emerged. A jellied blob with tiny structures at its heart, drifting into frame.
We vibrated with noiseless excitement. It was a cell – just one. Simple and superb.
There was a pause, a subtle shudder. The cell split into two.
I can’t say that I cheered. I roared. I thundered.
‘There it goes!’ Jack cried.
‘Oh, my God,’ Elena said, grinning from ear to ear.
‘There it goes!’ Jack punched his fists at nothing, the energy within him demanding an exit.
Chikondi simply laughed. He laughed and laughed, filling the gap left by inadequate words.
Jack’s imaginary money was well placed on caves. We found one tucked into a canyon wall, a low-hanging doorway leading to another realm. We had to crawl on our knees to get through the front passageway, sometimes splashing through the flow, but beyond that, the water had carved a magnificent inner chamber. Lei’s River, as we named it, joins two subterranean waterways there, and at their nexus is a glassy pool, chest deep and uncannily serene. Dazzling twists of crystals hang overhead, festooning the ceiling and walls like antique lace. The air in there is warm, thanks to steam vents running beneath the rock, and thoroughly sequestered from the harsh sun’s reach. It is the perfect place for life to develop, and, less importantly, for us to work.
As the only macroscopic life forms on Votum (thus far, anyway), we had no compunctions about setting up a field lab within the cave itself. There are no critters to knock it over, no weather to damage it. Everything we brought was sterilised, of course. We tread lightly in this sanctuary. But it is also a place I’ve come to inhabit fully. For the moment, the cave is home. I think, to answer the question I asked myself on Opera, a home can only exist in a moment. Something both found and made. Always temporary, in the grand scheme of things, but vital all the same.
One day I looked up from my worktable, where I’d been labelling rock samples to take back to the Merian. Chikondi was sitting by the pool, like always, watching his tablet intently and humming along with his headphones. He was running some sort of test on the bacterial samples he’d collected; any attempt to ask him what he was up to was answered with a vague mumble that indicated he was in the middle of puzzling something out and would fill us in when the idea was fully formed. Elena and Jack were standing beside a glittering twist of crystal, deep in a congenial argument about something to do with salinity. I admit that I wasn’t paying attention to the particulars. I was too busy watching the three of them and myself, each firmly in our elements. The cave is a reflection of us, in its way. Rock, water, and life, all of which need tools to examine them. All of which mean nothing if no one is there to observe.
‘We can’t go back,’ I said.
Elena and Jack looked at me. Chikondi did as well, though it took my comment a half-second longer to register with him.
I knew what I’d said was ridiculous, but the urge to say it had been growing inside me for weeks, and the rest came spilling out after. ‘Lawki 5 made it back to Earth, at least. That means everybody else is long since back. And if the Moon’s been abandoned, and if there are no functioning satellites, that means nobody is launching anything. We’re not the last of the Lawki program out here. We’re … we’re the last. Of anyone.’
Nobody looked as if my words were revelatory. They’d all been thinking this, too. Jack sighed. ‘We don’t have the equipment to do a long-term study here. Or on Mirabilis, or wherever.’
Chikondi nodded regretfully. ‘And the longer we stay,’ he said in a measured tone, ‘the more disruptive we are. Our visits are limited for a reason. We can’t have an influence.’ This was OCA ethics, word for word.
‘I know,’ I said. ‘I don’t disagree with any of that. I never have.’
Elena looked me in the eye. �
�Then what are you saying?’
I took a deep breath. ‘The interstellar engine has enough fuel to get back to Earth. Fourteen light-years, with a bit of wiggle room.’ I paused, choosing my words, trying to speak slow. ‘Thing is, that would also get us to Tivael.’
My words hung in the still air of the cave. Everybody understood what I was saying. Tivael was one of OCA’s earliest candidates for the Lawki program, but given its distance from Earth – over thirty light-years, or sixty years in transit – it was ruled out due to the limits of technology and the logistics of time.
From Zhenyi, however, Tivael was only thirteen light-years away. And I knew, as we all did, that there are three habitable planets in orbit around it. Going by the atmospheric data, life’s a near certainty on each of them. In particular, there’s one with an awful lot of greenhouse gases in the mix. Could be volcanic activity. Could be the natural state of things.
Could be something else.
Jack paced. ‘We …’ He stopped and thought. Like me, he was treading carefully. ‘Okay.’ He stuck his thumbs behind his toolbelt. ‘You’re saying that if we’re the last astronauts – the last at all – then we should prolong our mission, so that this kind of work will continue in the interim while Earth gets back on its feet.’
‘Yes.’
He gave a single nod. ‘What’s your evidence that OCA is gone, and that they’re not planning to rebuild?’ The question was delivered objectively, professorially. He was challenging my suggestion, as he rightly should.
‘I have none.’
‘What’s your evidence that there are no other humans in space besides us, right now?’
‘I have none.’
‘And why Tivael?’
‘Because we can,’ I said. I gestured around. ‘Why here?’
Chikondi nodded at that, but his attention was split, one eye still on his tablet as data compiled.
Jack continued. ‘So, you’re saying that even though we have no idea what’s going on back home, and can only speculate as to the current state of Earth’s spaceflight capabilities, in order to further the … the spirit of the mission we were sent here for, we should break the mission parameters entirely.’
‘Yes.’
Elena joined in. She leaned against the wall, arms crossed. ‘Even though we’d never go back. We’d never see Earth again.’
‘Yes.’
She looked at me hard. ‘We might live longer than our time on those worlds would allow for.’
‘I know.’
‘And if we did simply live out our lives, we’d do it in the Merian, off-planet.’
‘I know.’
‘Life support wasn’t intended to last through a second mission. We could die before our work there is done.’
I returned the look. ‘So, you’re saying we’ll either die old and housebound, or relatively young, in some kind of accident or disaster.’ I let that sit. ‘Those are the same options we’d get on Earth.’
She gave the smallest of smirks.
Jack paced more ardently. ‘Okay, but we didn’t make the decision to come out here. Thousands of people all over the world made that call. Do we have the … the … fuck, I don’t know – the right to decide this?’
‘Those thousands of people wanted this work done,’ Elena said.
‘Yeah, but those thousands of people are mostly dead,’ Jack replied. ‘We can’t say we’re doing this work for Earth if the Earth that’s out there now didn’t give us their thumbs up. We’d be doing it for ourselves.’
‘Would we be doing this for ourselves?’ Elena asked. ‘I’m fine dying out here, in concept, but I am looking forward to going back. I didn’t sign up for a one-way trip. None of us did. I’m not saying yes to this at all, I’m exploring the—’
‘Yes!’ cried Chikondi. ‘Oh, my – oh, my God. Oh, my God.’ He gestured frantically at his tablet, his body about to explode. ‘Everybody, please, come look, come look.’
‘What is it?’ I said, as we drifted over.
Chikondi held his screen up to us, his test results complete. ‘Look, look, look,’ he said.
My eyes scanned over the dense table of numbers and letters. I didn’t see it at first.
Elena saw it. She covered her mouth with her hand in surprise, but her smile was so big it inched out past her fingers.
Jack saw it. ‘Holy shit,’ he said.
The connection clicked. I saw it, too. ‘Oh,’ I gasped. ‘Oh, they’re—’
Chikondi beamed at us, his face reverent. ‘Look what we found.’
For a brief time in my life, I was ambidextrous. I remember a craft project in preschool where we were tasked with cutting shapes out of thick, coloured paper. My right hand quickly tired, my fingers cramped and weary within the confines of the handle (I imagine, in hindsight, that I’d been at it for all of five minutes). But this was no problem. I merely swapped the scissors into my left hand, and continued along. I wish I could still perform this trick, but alas, a teacher made me pick a side when we began to learn to write the alphabet. I chose right, because most kids used their right, and this seemed the least bother. The left has never served me well again. I don’t blame it for holding a grudge.
Molecules have a ‘handedness’ as well. This is called chirality, and if you’ve never encountered this concept before, it’s one of those that can make you sit back and stare into the distance for a while. I’ll walk you through it as simply as I can.
Take a moment to look at your hands (assuming that you have two; if you do not, borrow someone else’s, for science). Stretch them out and splay your fingers. Both hands, naturally, are made up of the same parts: wrist, palm, fingers, knuckles, nails. Matching ingredient lists. The exact same equipment.
If I were to give you a right-handed glove, you would not be able to wear it on your left hand. It wouldn’t matter how you flipped or twisted your appendage around. You might be able to cram your fingers in there, but the fit would be terrible, and you wouldn’t be able to use the glove properly. Even though your left hand has the same physical parts as your right, it will never, ever be the same shape.
The same is true for molecules. If you take two identical mixes of atoms and arrange them so that they are mirror-image configurations of each other, the molecules you’ve created are no longer the same thing, and the differences in how they interact with the world can be as different as night and day. To use the most famous (and disastrous) example of this, consider thalidomide, a compound that was widely prescribed to treat morning sickness in the 1950s. While right-handed thalidomide does indeed ease those symptoms, its left-handed twin causes severe birth defects. Chirality is a detail not to be ignored.
As a rule, life on Earth uses left-handed amino acids and right-handed sugars. This is an age-old puzzle of biochemistry, one that bleeds out into many adjacent fields. One can safely assume that when life began, it utilised whatever organic compounds were directly in front of it. Now, right-handed amino acids and left-handed sugars can easily be created in a lab. Anytime you whip up a batch of these things, you can expect an even spread of handedness. So, why, then, does life on Earth have a bias? Why would it feed on one and not the other, if both should have been naturally available? Why would there be only left-handed amino acids and right-handed sugars in the spot where our single-celled ancestors woke up?
The most likely answer is meteorites. We know that space rocks carry organic compounds aplenty, and if one of these smacks into a planet, it serves as something akin to a seed bomb lobbed into a vacant lot. If such a rock landed on Earth, and if, by either chance or the intricacies of chemistry, it carried mostly left-handed amino acids, you can see how life that developed in that delivery site might get accustomed to such homogeneity and pass that template on to its offspring.
But what if, instead, a handed preference is merely an intrinsic quality of life? What if life just works that way, for reasons we’ve yet to untangle? For a long time, we had only a single test subject to work with – the
Earth – and any scientist will tell you it’s impossible to determine anything from a sample size of one.
As we branched out to other worlds, the species we found also exhibited rigid preferences one way or the other. Life on Aecor is Earth’s opposite: right-handed amino acids and left-handed sugars are the norm there. Life on Mirabilis prefers everything left-handed. The findings from Lawki 5 are in concert with this; everything they found leaned one way or the other. This confirmed the suspicion that life does not have to arise under the exact same conditions as life on Earth, but it doesn’t answer the underlying question: are meteorites responsible for chiral preferences in life, or is a chiral preference a requirement of life?
In the pool in the cave carved by Lei’s River, Chikondi sampled one hundred species of single-celled organisms. None of them possess a chiral preference. They freely use amino acids and sugars of both types. They are, in effect, ambidextrous. And when Elena tested the water and Jack tested the rock, their findings confirmed what Chikondi’s indicated: the chirality of amino acids on Votum exists in a balanced ratio.
This means that chiral preference is not a requirement of life.
This means that emergent life forms do use whatever is on hand.
This strongly suggests that life on Earth only arose thanks to ingredients that originated off-planet.