Ring xs-4

by Stephen Baxter

  “I guess so. There’s no simple definition of where the Sun ends; there’s just a fall-off of density, steep at first, then becoming less dramatic once you’re outside the photosphere… Let me show you.”

  He touched his data slate, and the semisentient hull suppressed the photosphere’s glow. In its new false colors the Sunscape became suffused with deep crimsons and purples; the granules seethed like the clustering mouths of undersea volcanoes.

  “My word,” she murmured. “It’s like a landscape from a medieval hell.”

  “Look up,” Scholes said.

  She did so, and gasped.

  The chromosphere was a soft, featureless mist around the ship. And the corona the Sun’s outer atmosphere, extending many Solar diameters beyond the photosphere — was a cathedral of gas above them, easily visible now that the photosphere light was suppressed. There were ribbons, streamers of high density in that gas; it was like an immense, slow explosion all around them, expanding as if to fill space.

  “There’s so much structure,” she said. She stared upwards, her watery eyes wide and unblinking. Scholes felt disquieted by her intensity. He restored the transparency of the hull, so that the corona was overwhelmed once more.

  A sunspot — deep black at its heart, giving an impression of a wound in the Sun’s hide, of immense depth — unfolded beneath them, ponderously.

  “We seem to be traveling so slowly,” she said.

  He smiled. “We’re in free orbit around the Sun. We’re actually traveling at three hundred miles a second.”

  He saw her eyes widen.

  He said gently, “I know. It takes a little while to get used to the scale of the Sun. It’s not a planet. If the Earth were at the center of the Sun, the whole of the Moon’s orbit would be contained within the Sun’s bulk…”

  They were directly over the spot now; its central umbra was like a wound in the Sun’s glowing flesh, deep black, with the penumbra a wide, gray bruise around it. This was the largest of a small, interconnected family of spots, Scholes saw now; they looked like splashes of paint against the photosphere, and their penumbrae were linked by causeways of grayness. The spot complex passed beneath them, a landscape wrought in shades of gray.

  “It’s like a tunnel,” Lieserl said. “I imagine I can see into it, right down into the heart of the Sun.”

  “That’s an illusion, I’m afraid. The spot is dark only by contrast with the surrounding regions. If a major spot complex could be cut out of the Sun and left hanging in space, it would be as bright as the full Moon, seen from Earth.”

  “But still, the illusion of depth is startling.”

  Now the spot complex was passing beneath them, rapidly becoming foreshortened.

  Scholes said uncertainly, “Of course you understand that what you see of the Sun, here, is a false-color rendering by the hull of the Lightrider. The ’Rider’s hull is actually almost perfectly reflective. Excess heat is dumped into space with high-energy lasers fixed to the hull: the ’Rider refrigerates itself, effectively. In fact, if you could see the ship from outside it would actually be glowing more brightly than the photosphere itself…” Scholes was uncomfortably aware that he was jabbering.

  “I think I follow.” She waved her claw-like hand, delicately, at the glowing surface. “But the features are real, of course. Like the spot complex.”

  “Yes. Yes, of course.” Lethe, he thought suddenly. Am I patronizing her?

  His brief had been to show this strange old woman the sights — to give her the VIP tour. But he knew nothing about her — it was quite possible she knew far more about the subjects he was describing than he did.

  The Holy Superet Light Church was notoriously secretive: about the goals of this Solar wormhole project, and the role the old woman would play in it… although everyone knew, from the way she had been handled since arriving in near-Solar space — as if she was as fragile and precious as an eggshell — that this woman was somehow the key to the whole thing.

  But how much did she know?

  He watched her birdlike face carefully. The way her gray hair had been swept back into a small, hard bun made her strong-nosed face even more gaunt and threatening than it might otherwise have been.

  She asked, “And is this refrigeration process how the wormhole probe is going to work — to become able to penetrate the Sun itself?”

  He hesitated. “Something like it, yes. The key to refrigerating a volume is to suck heat out of the volume faster than it’s allowed in. We’ll be taking Solar heat away from the AI complex out through the wormhole, and dumping it outside the Sun itself; actually we’re planning to use that energy as a secondary power source for Thoth…”

  She shifted in her chair, stiff and cautious, as if afraid of breaking something. “Dr. Scholes, tell me. Will we be leaving freefall?”

  The question was surprising. He looked at her; “During this flight, in the Lightrider?”

  She returned his look calmly, waiting.

  “We’re actually in free orbit around the Sun; this close to the surface the period is about three hours… We’ll make a complete orbit. Then we’ll climb back out to Thoth… But we’ll proceed the whole way at low acceleration; you should barely feel a thing. Why do you ask?” He hesitated. “Are you uncomfortable?”

  “No. But I would be if we started to ramp up the gees. I’m a little more fragile than I used to be, you see.” Her tone was baffling — self-deprecating, wistful, perhaps with a hint of resentment.

  He nodded and turned away, unsure how to respond. “Oh, dear.” Unexpectedly, she was smiling, revealing small, yellow-gold teeth. “I’m sorry, Dr. Scholes. I suspect I’m intimidating you.”

  “A little, yes.” He grinned.

  “You really don’t know what to make of me, do you?”

  He spread his hands. “The trouble is, frankly, I’m not sure how much you know.” He hesitated. “I don’t want to feel I’m patronizing you, by — ”

  “Don’t feel that.” Unexpectedly she let her hand rest on his; her fingers felt like dried twigs, but her palm was surprisingly warm, leathery. “You’re fulfilling the request I made, for this trip, very well. Assume I know nothing; you can treat me as an empty-headed tourist.” Her smile turned into a grin, almost mischievous; suddenly she seemed much less alien, in Scholes’ eyes. “As ignorant as a visiting politician, or Superet high-up, even. Tell me about sunspots, for instance.”

  He laughed. “All right… To understand that, you need to know how the Sun is put together.”

  The Sun was a thing of layers, like a Chinese box.

  At the Sun’s heart was an immense fusion reactor, extending across two hundred thousand miles. This core region — contained within just a quarter of the Sun’s diameter — provided nearly all the Sun’s luminosity, the energy which caused the Sun to shine.

  Beyond the fusing core, the Sun consisted of a thinning plasma. Photons packets of radiation emitted from the core — worked their way through this radiative layer, on average traveling no more than an inch before bouncing off a nucleus or electron. It could take an individual photon millions of years to work its way through the crowd to the surface of the Sun.

  Moving outwards from the core, the density, temperature and pressure of the plasma fell steadily, until at last — four-fifths of the way to the surface electrons could cling to nuclei to form atoms — and, unlike the bare nuclei of the plasma, the atoms were able to absorb the energy of the photons.

  It was as if the photons, after struggling out from the fusing center, had hit a brick wall. All of their energy was dumped into the atoms. The gas above the wall responded — like a pan of water heated from below — by convecting, with hot material rising and dragging down cooler material from above.

  The wormhole probe, with its fragile cargo, would be able to penetrate as far as the bottom of this convective zone, twenty percent of the way toward the center of the Sun.

  She nodded. “And the photosphere which we see, with its granules and s
upergranules, is essentially the top layer of the convective zone. It’s like the surface of your pan of boiling water.”

  “Yes. And it’s the properties of the material in the convective zone that cause sunspots.”

  The convective zone matter was highly charged. The Sun’s magnetic field was intense, and its flux tubes, each a hundred yards across, became locked into the charged material.

  The Sun’s rotation spread the frozen-in flux lines, stretching them around the Sun’s interior like bands of elastic. The tubes became tangled into ropes, disturbed by bubbles of rising gas and twisted by convection. Kinks in the tangled ropes became buoyant enough to float up to the surface and spread out, causing spots and spot groups.

  She smiled as he spoke. “You know, I feel as if I’m returning to my childhood. I studied Solar physics intensely,” she said. “And a lot else, besides. I remember doing it. But…” She sighed. “I seem to retain less and less.

  “The Sun is my life’s work, you see, Dr. Scholes. I’ve known that since I was born. I once knew much about the Sun. And in the future,” she went on ambiguously, “I shall once again know a great deal. More, perhaps, than anyone who has yet lived.”

  He decided to be honest with her. “That doesn’t make a lot of sense.”

  “No. No, I don’t suppose it does,” she said sharply. “But that doesn’t matter, Dr. Scholes. Your brief is to do just what you’ve been doing: to show me the sights, to let me feel the Sun from a human perspective.”

  A human perspective?

  Now she turned and looked directly into his eyes; her gaze, watery as it was, was open and disconcerting, searing. “But your curiosity about my role isn’t what’s throwing you off balance. Is it?”

  “I—”

  “It’s my age.” She grinned again, deliberately — it seemed to him — showing her grotesque, yellowed teeth. “I’ve seen you studying me, from the comer of your eye… Don’t worry, Kevan Scholes, I don’t take offense. My age is the subject you’ve been politely skirting since I climbed aboard this flying refrigerator of yours.”

  He felt resentful. “You’re mocking me.”

  She snorted. “Of course I am. But it’s the truth, isn’t it?”

  He tried not to let his anger build. “What reaction do you expect?”

  “Ah… honesty at last. I expect nothing less than your rather morbid fascination, of course.” She raised her hands and studied them, as if they were artifacts separate from her body; she turned them around, flexing her fingers. “How awful it is that this aging was once the lot of all of humanity, this slow disintegration into decay, physical and mental. Especially the physical, actually… My body seems to crowd out my awareness; sometimes I’ve time for nothing else but to cater to its pressing, undignified needs…” She frowned. “But perhaps AS treatment has robbed our species of rather more than it has given us. After all, even the most vain, or most attention-seeking, refuse to be AS-frozen at more than, say, physical-sixty. So meaningful interaction is restricted to a physical range of a mere six decades. How sad.”

  He took a breath. “But you must be — physical-eighty?”

  Her mouth twitched. “That’s not a bad guess, for someone who’s never met an old person before… unless you’ve ever encountered an unfortunate individual for whom AS treatment has failed to take. These are humans in their natural state, if you think about it, but our society treats them as ill — to be feared, shunned.”

  Gently, he asked, “Is that what’s happened to you?”

  “Failed AS treatments?” Her papery cheeks trembled briefly, and again he perceived resentment, a deep anger, just under her abrasive, disconcerting surface. “No. Not exactly.”

  He touched her arm. “Look there… ahead of us.” There was a structure before them, looming out of the flat-infinite horizon, rising from the photosphere itself. It was like a viaduct — a series of arches, loops of crimson-glowing gas which strode across the Solar surface.

  Once again he heard her gasp.

  He checked his data slate. “Prominences. The whole structure is a hundred thousand miles long, twenty thousand high…” He glanced up and checked their heading. “We’re only ten thousand miles above the surface ourselves. We’re going to pass through one of those arches.”

  She clapped her hands in delight, and suddenly she seemed astonishingly, unnervingly young — a child trapped in a decaying husk of a body, he thought.

  Soon the arch through which they would pass was huge before them, and the mouths of the others began to close up, foreshortened. In this landscape of giants, Scholes found he had trouble visualizing the scale of the structures; their approach seemed to take forever, yet still they grew, thrusting out of the Sun like the dreams of some insane engineer. Now he could make out detail — there were places were the arch was not complete, and he could see knots of higher density in the coronal gas which flowed, glowing, down the magnetically shaped flanks toward pools of light at the feet of the arch. But despite all this the illusion of artifice persisted, making the structure still more intimidating.

  At last the arch swept over them, immense, aloof, grand. “Five thousand miles thick,” he said slowly. “Just think; you could hang the Earth up there, at the apex of that arch, like a Christmas tree ornament.”

  She snorted, and pressed the back of her hand to her mouth.

  He looked at her curiously. She was — he realized slowly — giggling.

  They passed through the arch; the vast sculpture of gas receded slowly behind them.

  Scholes checked his data slate. “We’ve almost completed our orbit. Three million miles of a Solar great circle traversed in three hours…”

  “So our journey’s nearly done.” She folded her hands neatly in her lap once more, and turned her face to the clear wall; corona light played around her profile, making her look remote, surprisingly young.

  He felt suddenly moved by her — by this lonely, bitter woman, isolated by her age and fragility from the rest of mankind… and, he suspected obscurely, isolated by some much more dramatic secret.

  He tried to reassure her. “Another hour and you’ll be safely inside the habitat. You’ll be a lot more comfortable there. And — ”

  She turned to him. She wasn’t smiling, but her face seemed to have softened a little, as if she understood what he was trying to do. Again she reached out and touched the back of his hand, and the sudden human contact was electric. “Thank you for your patience, Dr. Scholes. I’ve not given you an easy time, have I?”

  He frowned, troubled. “I don’t think I’ve been patient at all, actually.”

  “Oh, but you have.”

  His curiosity burned within him, like the Sun’s fusion core, illuminating everything he saw. “You’re at the heart of all this, aren’t you? The Superet project, I mean. I don’t understand what your role is… But that’s the truth, isn’t it?”

  She said nothing, but let her hand remain on his…

  He frowned. She seemed so fragile. “And how do you feel about it?”

  “How do I feel?” She closed her eyes. “Do you know, I’m not sure if anyone has asked me that before. How do I feel?” She sighed, raggedly. “I’m scared, Dr. Scholes. That’s how I feel.”

  He let his fingers close around hers.

  There was a subtle push in the base of his spine, and the sound of the Lightrider’s drive was a deep, low vibration, a seismic rumble he felt deep within the fabric of his body.

  Slowly, the little ship climbed away from the Sun’s boiling surface.

  4

  The flitter tumbled from the shimmering throat of the wormhole transit route from Port Sol to Earthport. Louise Ye Armonk peered out of the cramped cabin, looking for Earth. Mark sat beside her, a bookslate on his lap.

  Earthport was a swarm of wormhole Interfaces clustered at L4 — one of the five gravitationally stable Lagrange points in the Earth-Moon system, leading the Moon in its orbit around Earth by sixty degrees. From here, Earth was a swollen blue dis
c; wormhole gates of all sizes drifted across the face of the old planet like electric-blue, tetrahedral snowflakes.

  The flitter — unmanned save for its two passengers — surged unhesitatingly through the tangle of Interfaces, the mesh of traffic which passed endlessly through the great cross-System gateways. In contrast to the desolation of the outer rim, Louise received a powerful, immediate impression of bustle, prosperity, activity, here at the heart of the System.

  At the flitter’s standard one-gee acceleration the final leg from L4 to Earth itself would take only six hours; and already the old planet, pregnant and green, seemed to Louise to be approaching rapidly, as if surfacing through the complex web of wormhole Interfaces. Huge fusion stations — constructed from ice moons towed into Earth orbit from the asteroid belt and beyond — sparkled as they crawled above green-blue oceans. The planet itself was laced with lights, on land and sea. In the thin rim of atmosphere near the North Pole Louise could just make out the dull purple glow of an immense radiator beam, a diffuse refrigerating laser dumping a fraction of Earth’s waste heat into the endless sink of space.

  Louise felt an absurd, sentimental lump rise to her throat as she studied the slowly turning planet. At moments like this she felt impelled to make private vows about spending more time here: here, at the vital core of the System, rather than on its desolate edge.

  …But, she reminded herself harshly, the rim was where the Northern was being built.

  Louise had work to do. She was trying to equip a starship, damn it. She didn’t have the time or energy to hop back to Earth to play guessing games with some unseen authority.

  Growling subvocally, Louise rested her head against her couch and tried to sleep. Mark, patient and placid, called a new page of his bookslate.

  The little ship landed in North America, barely thirteen hours after leaving Port Sol — all of four billion miles away. The flitter brought them to a small landing pad near the heart of Central Park, New York City. Louise saw two people — a man and a woman — approaching the pad across the crisp grass.