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 supergranules, 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.