Clade

by James Bradley

  The sequence repeats itself twice more during the following minutes, three bursts of just over thirty seconds each, separated by roughly three seconds of silence; then, after the third sequence, it falls quiet.

  Jin and Noah sit without speaking, alert in case it begins again. Only when it is finally clear that whatever it was has stopped does Jin break the silence.

  ‘That was what it sounded like, wasn’t it?’

  Frightened that putting it into words will somehow dissipate what he has just heard, Noah struggles to form an answer. But eventually he nods. ‘I don’t know,’ he says. ‘Perhaps. I think so.’

  Over the hours that follow they perform the tests necessary to eliminate false positives, repeating each of them twice, then a third time. With so much junk in orbit it is important to be certain that they have not merely picked up some malfunctioning piece of military hardware, or a terrestrial signal reflected back at them by a satellite. But each time the results are the same: the source of the transmission was not terrestrial or from an object in orbit. Instead its motion was consistent with the rotation of the Milky Way, meaning it emanated from somewhere outside the solar system.

  As the transmission source begins to move towards the horizon, Jin seats himself next to Noah.

  ‘We need to talk to the observatory at Karoo,’ he says. ‘If it recurs they’ll be able to pick it up, confirm our results.’

  Although Jin knows Naledi, the supervisor of the South Africa facility, better than Noah, they decide Noah should make the request. Calling up Karoo’s details, he pings her to ask the observatory to scan the relevant patch of sky. Naledi pings them back almost immediately.

  Need more information.

  Anomalous intermittent radio source detected in Sagittarius, Noah replies. Exhibiting sidereal motion.

  Pulsar? Potential supernova?

  Not pulsar.

  Then what?

  Unclear. Coherent and repeating at 1420 MHz.

  A moment later her face appears on the screen in front of Noah. ‘Repeating how?’ she asks without preliminaries.

  ‘Three bursts 32.7 seconds in duration and 3.27 seconds apart. The entire sequence seems to have been repeated three times, with a gap between each sequence of 32.7 seconds.’

  ‘You should have heard it,’ says Jin, leaning in. ‘Clear as day.’

  Naledi looks away, absorbed in some mental calculation. Then she nods. ‘Send me the data; we’ll see what we can do. And Noah?’

  ‘Yes?’

  ‘I’ll make sure we keep this to ourselves.’

  Just before dawn, as the source of the signal passes below the horizon, Noah walks outside. It is cold, the desert air dry. To the east the approaching morning is pale pink, the sky above almost colourless. He knows – they all know – the significance of the signal’s frequency, which sits in the band known as the hydrogen line, the clear spot in the electromagnetic spectrum at which a signal would suffer the least interference. Turning to the west he tries to pinpoint where the source of the signal must be by now, aware it will be in range of Karoo in an hour or two. Looking down he realises his legs are shaking, that he is frightened not just because they might not find the signal again, or it might be dismissed as an anomaly, but because it might really be what it seems to be.

  8

  Noah first conceived the project a year after he started postdoctoral work. He had been involved in a program dedicated to sifting data from the old space telescopes for evidence of methane and other fingerprints of life, when he began to sketch out a proposal to use the array to search for signals from alien cultures.

  It was not a new idea. For much of the second half of the twentieth century scientists around the world had cooperated on programs designed to scan the skies for alien transmissions, many of them believing it would be only a matter of time before evidence of other life and civilisations was found. But as the decades passed without results, that conviction began to wane. In the early years of the twenty-first century there was a brief renewal of interest, spurred by the suggestion that life might lurk in the oceans of the moons of Saturn and Jupiter, and by the discovery of planets around other stars.

  But that interest didn’t last. Faced with the escalating environmental crisis and impoverished by debt and economic stagnation, governments began to cut back on investment in astronomy, diverting their resources to research into alternative energies and mitigation strategies. Amongst the first programs to be cut were those related to the hunt for alien intelligence. There was little reason to keep them: more than sixty years of searching had found no evidence at all, nothing, in fact, except silence.

  Exactly why those searches failed was impossible to know. Perhaps life was rare, intelligence even more so. Perhaps humans arrived too late or too early and the heyday of galactic civilisation had already passed, or lay billions of years in the future. Perhaps the assumption that others would use radio to communicate had been mistaken, perhaps the search should have concentrated on laser signals, or neutrinos. Or perhaps it was simply that there was nobody out there to find.

  The project Noah designed was an attempt to step past these failures and begin again. The first searches for signals had concentrated on scanning the entire sky in tiny sections, focusing on each part for a few seconds before moving on. The problem with this approach was that if the radio source was a beacon that sent a signal once an hour or once a day or once a year, it was highly unlikely to be detected. So in its place Noah proposed to direct a search into the galactic plane, where the stars are densest, and then to search each sector for as long as possible, using the computational power of the array’s system to sift the data for anomalies.

  His superiors regarded the project as quixotic and a waste of resources. And for the past four years his efforts have yielded nothing: no signals, no suggestion there is anything out there except emptiness. Until now.

  9

  As a child he was always afraid. Sound was too close, too huge. Things moved too fast. People came and went, looming into view and disappearing, their movements erratic, unpredictable, their voices a clamour of undifferentiated noise.

  In his mind that time seems to stretch on and on. He has read enough about the science of memory, the way it encodes in the brain, to know he should have forgotten, but he hasn’t; instead it remains vivid, unsettlingly near at hand.

  He remembers the first time he stopped being frightened. He was with his therapist, Rayna – he recalls the office, the hum of the air-conditioning, the line of puzzles on the table. She had placed him in a plastic chair at the table and then sat opposite him. He was afraid – as he always was – but Rayna didn’t try to touch him or talk to him.

  Eventually he felt himself relax into the sense of calm Rayna and the office projected. Finally she took a breath and introduced herself. Usually when people spoke it was like cymbals clashing, but her voice was gentle, soothing.

  ‘I don’t need you to talk to me, Noah,’ she said. ‘I’m okay if we just sit here.’

  She was looking past him, her attention focused somewhere just beyond him. And though he didn’t understand it quite then, in that moment something unknotted inside him.

  10

  As Noah and Jin wait for Sagittarius to rise the following evening a hush falls over the control room. They have done their best to keep the circle of those who know about the signal small, but inevitably word has leaked out and several other technicians have gathered to wait with them.

  Noah is tense, hyper-alert. He has not slept, does not think he could if he tried. During the afternoon he had gone back through the data, but after analysing and reanalysing the readings he is next to certain the signal emanated from a star five hundred light years away known only as SKA-2165. M-class, seven known exoplanets, two in the habitable zone.

  Yet despite its strength and clarity the night before the signal has not been detected elsewhere. Late in the morning Naledi pinged them to say they had found no trace of it, and suggested they contac
t the Atacama array in Chile.

  Noah was reluctant, uncomfortable with the idea of letting more of the astronomic community learn of the signal before they had more conclusive evidence. But at Jin’s urging he acceded. The leader of the Chilean team was more sceptical than Naledi, and perhaps with good reason, for despite agreeing to concentrate on SKA-2165 they had detected nothing.

  As Noah has reminded Jin a number of times, the failure of Karoo and Atacama to detect the signal is not necessarily significant. Noah’s program was designed on the assumption that the power demands of broadcasting an omnidirectional signal are prohibitive, meaning any transmissions are more likely to be produced by beacons, either sweeping a single beam like a lighthouse or sending a rotating sequence of short signals to a series of specific targets. In both cases it was possible for hours or days or even longer to pass between each signal. This would explain why the signal had not been detected before now: nobody had looked at the right moment. But it also meant that waiting for it to recur might be a long process.

  There is another possibility. If the signal really is a beacon it seems logical to Noah that it is designed to draw their attention, and that if they look more closely they will find another signal emanating from the same source, perhaps a longer signal with more information. And so while they wait for the signal to recur they will also look for that.

  11

  After that day with Rayna things were different. He wasn’t just less frightened, he felt connected somehow, less lonely. It didn’t happen all at once, of course, but he remembers a moment on the train, the colour of the light on a map of destinations, and somewhere in its warmth a sense of peace.

  His mother did the best she could. Although there were no longer programs to help parents with children who needed therapy, she managed to find somebody locally who helped develop a set of exercises for him. Looking back he can see they were designed to help him with language by moulding his perceptual processes, to help him hear the way others did, but at the time he mostly enjoyed the calm he felt when he sat with Summer and worked through them. Although he loved her he was also afraid of her, of her frustration, but when they did the exercises she was always patient, always gentle.

  He knows enough now about the science to understand the differences between his brain and those of most people. Where they think in language he thinks in image and symbol, where they think in social time he thinks in space and patterns. Yet he still finds it difficult to grasp the ease with which others seem to accommodate language, the way it supports them, sustains them: for him it has always been clumsy, artificial even.

  By the time he was ready to start school he had some words, although not enough. And school terrified him, especially at first. The other children weren’t cruel, but they were loud, baffling, unsettlingly erratic. Some days he barely spoke, just sat drawing diagrams or staring out the window. He had discovered astronomy by then, and when things became too much he would retreat, losing himself in calculations of the orbits of the planets, or by imagining he was out there, in the silence of the void. He can still remember the shape of the window in his first- and second-form classrooms, and the way the sky moved against the roofs in the streets on the walk home from school.

  Yet he was still afraid so much of the time. Sometimes he would forget he was meant to stay home, and head out into the fields or down to the sheds to watch adults working. It was fascinating to him, the way they concentrated on their task. For a while after they moved to the country there was a man called Sean who built boats in his barn, beautiful craft that echoed the shape of the boats that had been used in the area thousands of years before. Noah watched the way the wood formed itself under his hands, the emergence of order. It was the plane he loved best, not the electric one but the handheld one, the way it moved with the grain, the wood curving up from its blade in long shavings. He found most smells overwhelming, disgusting, but the scent of the wood, its hot whiff of burning, was magical.

  12

  As the night wears on they grow restive, distracted by their failure to detect either the signal or some other transmission on another frequency. Worried that they have made a mistake, or the equipment is faulty in some way, Jin checks the systems over and over again, but finds nothing wrong.

  Although Noah tries to disguise his anxiety he becomes steadily more agitated, the possibility that the result will not be repeatable, that it will turn out to have been nothing more than an anomaly, almost unbearable.

  And so he tells himself it is just a matter of looking, that they will find it again no matter what. The array is one of the most sensitive deep-space observation facilities on Earth, capable of picking up whispers from across the universe, its system powerful enough to sort through the extraordinary density of that information, to comb it for the tiniest details.

  Sometimes he finds it dizzying, the thought of all that computer power, the depth to which they can probe. From here it has been possible to observe hundreds of billions of galaxies, to not just plot their positions but map their structure and movement, the shift and flow of galactic clusters and superclusters through the fabric of the universe.

  13

  In the days after Adam’s call Noah walls himself off, refusing Adam and Ellie’s repeated attempts to contact him. He knows they are concerned about him, are worried about his reaction, but he is not willing to discuss it.

  The truth is they are unable to understand. He doesn’t just not want to see her, he can’t see her, can’t bear being reminded of what happened. He’s angry, he knows that, but he is also afraid, not just that she might hurt him again but that he might let her, that he might not be able to prevent himself from forgiving her. And so he throws himself into work, concentrating on the preparations for his coming trip to the array. Eventually Lijuan calls him, and after a short conversation tells him Adam is there with her, that he wants to speak to him.

  He almost hangs up but before he can, Adam comes on the line.

  ‘Noah,’ he says. ‘We’ve been trying to contact you. Are you okay? I understand if you’re angry or frightened, but you need to see her.’

  Noah stares ahead, willing the conversation to be over. ‘No I don’t.’

  ‘Not for her sake, Noah, for yours. Before it’s too late.’

  His tone of voice makes Noah hesitate. ‘What do you mean?’

  Adam says, ‘She’s sick, Noah. Very sick.’

  14

  Near dawn, when the star sets, they ask the system to collate the data and share it with them, but no matter how many times they review it there is no sign of either a repeat signal or a second transmission. Despite his determination to stay calm Noah is perturbed, alarmed that the discovery is slipping away from him. It makes no sense: why send these squirts of random noise? Why not send something that can be recognised, audio or numbers, some kind of binary code? Why broadcast noise into space?

  15

  Although Adam and Ellie offer to accompany him he is determined to visit her on his own, picking a time he knows he will be undisturbed by other concerns. When the day arrives he walks the short distance from the train station to the hospital, rides the elevator up to her room. Outside her door he stops, almost turns and runs away, but then he steels himself and steps inside.

  He does not recognise her at first. She is lying in the bed nearest the window, her once-blonde hair now grey, her face drawn. As he approaches she turns towards him.

  ‘Noah,’ she says.

  He doesn’t answer, cannot speak.

  She pushes herself upright, her face tightening in pain. ‘You came. I wasn’t sure you would.’

  When he still doesn’t reply she gestures at the seat beside her bed. ‘Please,’ she says, ‘sit down.’

  He is trembling, unwilling to let her see his distress.

  ‘Did your grandfather tell you to come?’ Her face shows she knows the answer to that without him telling her. ‘So you know . . .?’

  Noah nods and she looks away for a minute. ‘He
said you’re going away soon.’

  ‘To Western Australia,’ he says in a strangled voice. ‘I have time on the array out there each year.’

  ‘He says you’re looking for alien life.’

  ‘Not life. I’m looking for signs of intelligence.’

  ‘You think it’s there?’

  ‘Perhaps.’

  Her face softens. ‘When you were a boy you were so fascinated by the stars. We had a telescope, do you remember? You were amazing. You learned the names of the constellations and the planets. Sometimes you would recite them.’ She smiles, then catches herself. ‘I’m sorry, it’s not fair of me to talk like that.’

  ‘It’s okay,’ he says, less stiffly.

  For a long moment the two of them are quiet. Finally Summer asks, ‘Are you happy? In your work? In your life?’

  Uncertain of how to answer, he hesitates. ‘I suppose,’ he says at last. The feeling welling in his throat is choking him.

  She closes her eyes. ‘I’m glad,’ she says. ‘You know, I don’t expect you to forgive me. It was wrong. I know that now, I knew it then. I told myself I was doing it for you, that it was better for you not to be with me, but really it was because I didn’t know what to do, and I thought that by running away I could make everything stop, but I was wrong. I just made it all worse, so much worse.’ She stops. ‘I need you to know something, though. That it wasn’t because I didn’t love you – I did, so, so much. It’s just that I was afraid.’

  She turns on her side. ‘I have something,’ she says. ‘Something I want you to have. Here, get me my bag.’

  From her bedside cupboard he takes out her bag, which she opens with one hand. After a search she pulls forth a child’s plastic toy, offers it to him.

  Turning it over he recognises it as the Sixteenth Doctor, one of a collection he had as a child.