Sunfall

by Jim Al-Khalili

  Even though there was no reason why she should be held personally responsible for saving the world, she still felt frustrated by her helplessness. But all she could do was what was asked of her, to provide information about potential CMEs, which she fed back to the UN task group working on the magnetic pulse devices.

  She crawled out of bed and plodded to the bathroom. The photovoltaic glass of her large bedroom windows had already reacted to her movements and changed from opaque to clear, allowing the early-morning sun to stream in, and she guessed it was already about six-thirty. ‘Coffee on. Latest solar update,’ she croaked. Reassuringly, her home AI had no problem recognizing her voice and responded with a breezy Good morning, Sarah, and she heard the reassuring sound of the coffee machine clicking on in the kitchen. The cats wouldn’t even let her sit on the toilet in peace and were now both weaving in and out of her legs. Serves me right, being away for so long. They’ve got used to being fed at this ungodly hour by Mrs Azevedo. That reminded her: she made a note to check that her upgraded house bot was ready for collection, although she had to admit she’d been enjoying getting back to her old household chores, away from the media spotlight and polluted UN politics.

  She tapped the big bathroom mirror and its interactive screen burst to life, showing her several images of the latest solar activity. The European Space Agency’s Solar Orbiter satellite, the closest man-made object to the Sun, was revealing an even higher flare activity than yesterday, which meant an increased risk of CMEs. Even more worrying was the fact that several CMEs over the past couple of days had been ejected from a region close to the Sun’s central disc and were being sprayed out in the plane of the inner planets’ orbits, although so far none towards Earth. She had stressed in her report to Hogan that few CMEs ever scored a direct hit on Earth. And the seriously disruptive and dangerous ones occurred on average once a century.

  She tapped off the interactive screen on the mirror and the technical display was replaced by her half-awake and dishevelled reflection staring back at her. She turned away and headed for the shower. It was going to be another warm and sticky day and she enjoyed the invigorating coldness of the water. Then, dressing in an old pair of jeans and T-shirt – it was a relief to be back in her normal scruffy clothes again – she headed into the kitchen to grab a coffee. She’d pick up breakfast when she got to the Institute.

  Five minutes later she was ready to leave. The traffic shouldn’t be too bad this time of the morning, especially since she was able to weave around the cars on her bike. Besides, the roads were significantly quieter these days. The Rio riots had been particularly violent, with vehicles set on fire and shops ransacked. So, many people were still afraid to go out. She picked up her crash helmet and two lithium-air batteries from the induction pad they had been charging on. ‘Leaving apartment. Back this evening,’ she said hastily, and her AI system responded with a warm, Thank you, Sarah. Enjoy your day. She hurried down the two flights of stairs, and then thumb-activated the door down to the small basement carpark. It was seven-fifteen.

  In the basement, she walked over to the dimly lit far corner where she kept her motorbike. The 100bhp Yamaha was her pride and joy and probably the thing she had missed the most while in the States.

  Just then she heard a familiar voice behind her. ‘Hi, Sarah, when did you get back?’

  She turned to see Luca Aumann, the Austrian journalist from the ground-floor apartment, who was with his young daughter. ‘Oh, morning … Luca. Yes, I got back a couple of days ago.’ She smiled at the girl, whose name came to her just in time. ‘Hello, Laura. Ooh, I like your hair.’

  Laura smiled back shyly and held her blonde pigtails one in each hand. ‘Papa helped me do them,’ she said in a soft voice. Sarah recalled that the girl spent half her time with her father and the other half presumably with her mother, somewhere.

  She turned back to meet Luca’s eyes and was instantly lost for words. Luca Aumann always made her feel like an awkward teenager and she was suddenly conscious of how scruffy she must appear to him in his expensive-looking jacket and open-neck shirt. How did he stay so cool in this humidity?

  She suddenly realized she had been staring at him without saying anything and felt her cheeks begin to flush. But Luca put an end to her discomfort. ‘Well, it’s good to see you again. Laura and I are off to the park to feed the ducks before school, aren’t we, Laura?’ The girl nodded and showed Sarah the paper bag she was holding. ‘Anyway, now that you’re back, Sarah, you should come down and have dinner with us one evening.’

  ‘That’d be lovely, thank you. Say hello to the ducks for me, Laura.’ Sarah gave the little girl a brief wave before turning to her motorbike. She heard their car door close as she clicked the batteries into position. She put on her helmet, swung her leg over and fired up the engine, relieved that it started on first go. She sat for a moment enjoying the artificially generated rumble of a fossil-fuel internal combustion engine. Reversing quickly, she headed up the ramp, out onto the road and into the morning traffic.

  Interlude

  Wednesday, 13 March – STEREO2 spacecraft

  At 10:28 Coordinate Universal Time – 07:28 in Rio de Janeiro – the two Solar Terrestrial Relations Observatory spacecraft moving in separated heliocentric orbits, one far ahead of the Earth and the other lagging behind, recorded the approach of a large coronal ejection which, a few minutes earlier, had been expelled by the Sun and then immediately picked up speed as it travelled through space. Their combined data placed the CME on a trajectory that would almost perfectly rendezvous with Earth.

  At about the same time that the two spacecraft first detected the ejection, which was just over eight minutes after it had actually left the Sun’s surface, high-energy photons, both ultraviolet and X-ray, hit the Earth’s upper atmosphere, ionizing its gases. In itself, this caused no harm to the biosphere, but the levels of ionization were so severe that over half the world’s radio communications were temporarily wiped out, disrupting the information flow from many satellites. And with much of the global internet connectivity now using dual laser–radio technology, with data being sent and received between thousands of drones that filled the sky at an altitude of 20 km, the disruption to radio signals was enough to shut down large parts of the internet too.

  This meant that when the warning signals sent by both STEREO2 spacecraft that a CME was on its way arrived at the near-Earth satellites thirty seconds later, they went no further. So, no one knew that just eleven minutes after that, the CME’s vanguard of high-energy particles – protons moving at close to the speed of light – would hit the Earth. Many of these protons would collide with molecules of air in the upper atmosphere, causing a shower of new particles, such as muons, to rain down to the surface. But with Earth’s depleted magnetic field unable to deflect them, many of the original protons from the Sun would themselves also make their way to the ground. They would be deadly.

  For many years, several strategies had been in place to cope with a CME-induced geomagnetic storm. These had been reviewed and revised in the light of the Earth’s weakening magnetic field. The Hogan committee had then recommended further strategies following the Air India disaster, including a shut-down of all non-essential communications and switching from large electricity grids to local generators. Cloud communications and data transfer would also switch from a combination of laser and radio transmission to laser only, since drone–drone and drone–Earth radio signals would be dramatically compromised by any large geomagnetic disturbance. None of this was implemented, since no one knew this particular coronal mass ejection was coming. Until it was too late.

  29

  Wednesday, 13 March – Rio de Janeiro

  Joining the orderly AI-controlled morning traffic, Sarah enjoyed the freedom of being, almost, in complete control of the bike. She turned off her AR feed as she focused on the road – the chances of the Sun misbehaving during her half-hour journey seemed slim. As in most big cities, Rio de Janeiro’s entire transportation
system was run by an AI Mind that linked together and coordinated all the autonomous traffic on its roads, as well as all the traffic lights, which were needed for those vehicles still under the control of their human drivers. And the Mind would not allow her to exceed the speed limit or jump any lights even if she had wanted to: it would take over her bike’s computer, commanding it to activate the brakes and slow down.

  The traffic was light as she sped north up Rua de Santana, passing the abandoned and burnt-out vehicles on the side of the road – a reminder of the civil unrest the city had endured over the past few weeks. But she would soon hit the commuter rush hour when she reached Avenida Presidente Vargas, which ran into the city from the west. As she reached the intersection she dropped the revs on the bike’s throttle in anticipation of the Mind taking over control of her brakes. She still found this mix of manual and remote control of her bike disconcerting and preferred open country roads away from AI control, where she could manually apply her own brakes if and when necessary.

  The first sign that something was wrong was when her brakes failed to activate automatically as she approached the busy intersection that got her onto the freeway. Strange. She was always stopped here by the Mind, even if for just a few seconds. Dropping down to a lower gear, she edged forward carefully. There was heavy traffic on the four lanes of the eastbound side of the road, which she had to cross, and it was completely stationary. It had been a long time since she had witnessed such an old-fashioned traffic jam – it just wasn’t the sort of thing that happened in large cities any more. It occurred to her that, not so many years ago, this sort of scene would have been accompanied by a cacophony of revving internal combustion engines and car horns honking impatiently while drivers leaned out of their windows to shout at each other. This morning, everything was eerily quiet. People had quickly got used to relying on their cars’ computers to do all the driving while they sat in comfort within their air-conditioned environment.

  Weaving her way carefully around the stationary cars blocking her path, she noted the bemused looks on the faces of the passengers, suggesting that whatever had stopped the traffic had only happened recently. None of the cars on the westbound side were moving either, so it had to be a problem with the city’s AI. But the Minds that ran the very largest megacities around the world simply didn’t go down. Ever. She felt a creeping unease. Pulling over, she dismounted and blinked on her AR. The feed was dead.

  No reason to freak out just yet, girl – just because the entire net is down!

  She steadied her breathing. Logic before panic. After all, she’d spent the last few days worrying about the Sun’s abnormal activity, but that did not mean that this internet blackout was in any way related.

  OK, think. If a solar blast really has knocked out radio-wave connectivity, then maybe I can still use my wristpad. Like her computer back in the apartment, it had a direct lasercom link to the STEREO2 spacecraft, which meant it didn’t have to route through any Earth-orbit commsat. She quickly established a link and scanned recent solar activity.

  Fuck.

  She examined the data streaming across her vision and gasped. The incoming CME was a monster. Its size, speed and energy density were off the charts. Could it be a mistake? No, the stats would have been cross-correlated between the STEREO2 spacecraft. Her heart was now pounding as she did a quick mental calculation, trying to suppress her growing panic. The spacecraft had first detected the CME and begun sending their alert to Earth a few minutes ago, which would also have been when the electromagnetic pulse that must have brought down the net had hit.

  Oh, shit … this is really, really bad. It means we’ve got at best ten to fifteen minutes before the proton blast. She knew that others at her institute and elsewhere who had direct links to STEREO2 would also be aware of the incoming CME, but they’d have little time to do much.

  Under normal conditions, with a healthy magnetosphere, the proton shower that preceded the arrival of a CME would not be cause for concern. But in its weakened state, the field would not provide an adequate shield. She estimated that it could potentially be worse than the radiation fallout from a thermonuclear blast. And that was before the main ejection hit the Earth in a day or two. Worst of all, with the net down there was no way to warn people. It was the stuff of nightmares.

  She surveyed her surroundings on the highway. Everywhere, people were getting out of their cars. They have no idea what’s about to happen. And they can’t stay here, exposed. Even in their cars they’ll be like sitting ducks. It would be like hiding inside a cardboard box on a firing range.

  She ran to the nearest group of half a dozen well-dressed businessmen and -women and, instead of speaking in English and relying on their universal translators, she started to explain as best she could in her broken Portuguese that she was a scientist and she knew what had caused the blackout. Things were about to get very bad and they needed to find shelter – anywhere that could give them protection from the radiation from the sky.

  They just stared at her as though she were mad. She switched to English in the hope that some of them would understand, either directly or through their UTs, and could pass on what she was saying.

  ‘Please. I work at the Solar Science Institute. We’re about to be hit by dangerous radiation from the Sun and we only have a few minutes. Everyone needs to get off the road.’

  One young man turned to the woman next to him and muttered something that caused her to raise one hand to her mouth and conceal her laughter. An overweight middle-aged man who was already starting to sweat in the warm morning sun spat an impatient insult at Sarah in Portuguese, which she understood perfectly well and chose to ignore. She knew how she must sound; these days the world was full of doom-mongers preaching that the end of the world was nigh, some more wildly than others. But these people had to listen. She grabbed a well-dressed middle-aged woman firmly by the shoulders and spoke as clearly as she could. ‘Listen to me. The internet blackout is because of the Sun. And it’s going to get worse … and if you’re exposed to it you could die. Please … please. Everyone needs to find some shelter. Now.’

  She realized she was ranting, and the look on the woman’s face confirmed how crazy she must sound.

  She felt a hand on her own shoulder pulling her away and she let go of the woman. She stumbled backwards, losing her balance, and fell heavily, grazing her hands as she reached down to break her fall.

  More people had gathered to check what the commotion was. A few, who had heard part of what she’d said, were now in animated conversation. A mother pulled her two young children from a car and, holding their hands firmly, began pushing her way through the crowd to the side of the road. Sarah sat, dazed, on the ground as a circle gathered around her and stared, while others lost interest and returned to their air-conditioned cars. A few people were looking up at the sky, shielding their eyes from the sun’s glare.

  She was helped to her feet by an embarrassed-looking young couple. Feeling both humiliated and enraged in equal measure, she began to explain to them, ‘Please, you have to listen—’, but they smiled awkwardly and retreated back down the road.

  Time was running out. What more was she supposed to do?

  Instead, a primal survival instinct kicked in, snuffing out any feelings of moral obligation. Well, fuck you then. Stay out and enjoy your suntan. She picked up her helmet and ran back to her bike. She knew where she needed to get to.

  She swung her leg over the bike, hit ignition and revved the engine, ignoring the soreness in her right hand from her stumble. She turned the bike around and looked frantically for a route to get across the multiple lanes of traffic. She needed to head back the way she’d come, back to the Santa Barbara tunnel, but by now traffic was backed up in both directions along Rua de Santana, which had been so comparatively empty a few minutes ago.

  People were standing around in the road ahead of her but, realizing that she had no intention of slowing down as she sped between the stationary cars, they scattered
as she bore down on them. She left a tirade of obscenities in her wake. Tough. No time for pleasantries.

  Suddenly, a car door swung open in front of her without warning and she had to slam on her brakes and swerve, still clipping the door sharply with her back wheel. The young occupant of the car jumped out and looked for a second like he was going to pull her from her bike. She ignored him and weaved her way onwards.

  Up ahead of her several cars had tried, unsuccessfully, to turn around, causing utter chaos. Already voices were being raised and the first punches thrown. How quickly the rule of law broke down – how volatile the public mood was at the moment. The road looked completely blocked. She let out a scream of frustration.

  With less than ten minutes before she needed to get to safety she knew she had to get off the highway. The narrow winding lanes of the Santa Teresa district were above her and she gunned the bike onto the pavement, up a steep grass slope and across flower beds. Suddenly, she was on a quiet residential road.

  As the crow flies, the tunnel was less than a kilometre away, but would she have enough time to make it along the twisting steep roads on the Santa Teresa hill? She had to try. Revving the engine with renewed purpose, she sped off.

  Twice her bike skidded as she wrestled to keep it on the winding road. Adrenalin was now surging through her, the single-minded determination to reach the tunnel blocking out all other emotions. She braked hard approaching another sharp U-bend, then gunned the throttle again with a twist of her right wrist even before she had straightened up. Too late to react, she saw a group of young boys playing football in the middle of the road. She slammed on her brakes again. Too hard. The tyres screeched as the bike swerved one way then the other. There was nothing she could as she lost her balance, still travelling at speed, and fell onto the road with the bike on top of her.