The Time Surgeons
Chapter 14 Variables

According to legend Achilles, the mighty hero of the Trojan War, had been offered a choice. He could choose a life of quiet, the life desired by most men, and reach an obscure, forgotten but contented old age. Or he could choose a life of glory, outshining his fellows but never returning home.

A star is granted a similar choice, though in its case the choice is given to it: by the size of the giant molecular cloud from which it forms, and by the complex dynamics of that stellar nursery as the star and its siblings begin their long journeys from dust to glory.

If by the time the cloud has dispersed they have gathered too little of the cloud to themselves they may not ignite at all, and be condemned to wander the eternal dark as dim rubies, with nothing but the dull heat of their contraction to mark their passing.

Gather some more gas, and when they condense to sufficient density the nuclear fires of fusion will light, and they will shine like beacons in the cold night that stretches for unimaginable distances around them. With not too much mass they will be red dwarves, glowing like embers, far dimmer than the Sun that warms planet Earth but still beacons in the sky. They burn slowly, so despite their low mass they are the Methuselahs of the universe, continuing their slow and steady burn for hundreds of billions of years, perhaps even to the end of the Universe itself.

More mass still and they will shine with a blinding glare, warm enough to nurture planets far from their boundary, long-lived enough for life to appear and thrive in their heat and light. Such was the Sun around which planet Earth revolves. Eventually these stars too will die, expanding to become red giants that devour their planetary children. By then, 10 billion years or so after their birth, perhaps any life they nurtured will have found a way to escape its fatal nursery.

But start with eight, ten or more solar masses, and the star will blaze in a glory as bright as it is short. After perhaps only a few million years, having burnt all its fuel it will collapse and explode in an outpouring of energy that can outshine its entire galaxy. Such a star can never live long enough for life to arise under its glaring brilliance; but the ferocity of its death could destroy life around other stars, even as far away as fifty light years. Ironically, the ashes of its death will seed space with the metals that later life might depend upon.

Fortunately, no star that bright exists close enough to Earth to be a danger. The nearest would be a sight for people to be amazed by and astronomers to study, with a short-lived frenzy matching that of the star’s final song, comfortable in the assurance that no harm would come to them, only knowledge.

But there are other ways for a star to die. Small and obscure, white dwarf stars abound. Some have companions. Some of those companions are close enough for the white dwarf to feast on matter drawn off from them, siphoned through a straw of gravity onto the dwarf’s surface. Enough of that stellar feeding and the mass of the white dwarf can exceed a critical limit, beyond which runaway nuclear fusion will ignite. The star, that could otherwise expect a long life of slow decay, will briefly match its larger cousins in the fury of its detonation.

Even rarer might be two white dwarfs, engaged in a dance that could last an eternity, or perhaps end in a merger of death.

There are no such stars known near Earth.

But stars move. And thirty millennia is a long time.

Pachmeny was bored. She knew a Student was not the equal of her Sage, but why did that mean she had to do rote work that a trained monkey could do? Yes, it was the way of the world and every Sage had once been a Student too. In Pachmeny’s view that did not excuse it. Surely if her Sage had suffered through the same process he should have been less, not more, likely to inflict it in his turn.

How did we ever get out of the caves – twice, she grumbled in the privacy of her mind, before sighing and turning back to her work.

Her Sage, Shemsak the Exact, studied the stars. For all her grumbling, Pachmeny knew she was lucky to be his student, and that if a trained monkey could do her work it would have to be an exceptional one. Shemsak had made his name, and achieved his own Temple in the sprawling grounds of the great center of learning that hosted it, by conceiving, designing and building a way to electronically image starfields at unprecedented sensitivity and resolution, an advance that had spawned many lines of investigations into the cosmos. But the inconstant air above them shimmered and shivered, distorting the light from the stars, even if the telescope were on a remote peak far above the fog and dust of the Earth. The Sages wanted more, and bent their noble heads to the task.

Pachmeny’s age had not had a space race. There had been nothing to press resources into such a quixotic quest as sending men into the cold hard vacuum of space; nor even the more prosaic quest of sending machines there. People had imaginations and brilliance, but these were pressed to other concerns. Nor had this age had a mad dictator bent on conquest at the right technological time, whose lusts would help push rockets from toys to machines powerful enough to pique the interest of those with more peaceful concerns.

In another age men might have put a telescope into space, far above the dance of the air, where the cold pinpoints of starlight could fall unwavering onto one of Shemsak’s devices. Men in this age thought of it too, but the task was too hard and the expense too high for too uncertain a return. So they found other ways.

In other areas their technology was advanced. They knew why the starlight juddered and that if they could measure it, they could distort a mirror to correct it; they had the technology to achieve both. And so on a high mountain they built a giant telescope, able to measure the distortions in the atmosphere above and ripple its mirror to send the errant light beams back on the right course, into the most advanced Shemsak Detector ever built.

As the great machine came online many astronomers hardened their elbows and jockeyed for access to its data; some succeeded. But none could begrudge Shemsak being granted the greatest share of the bounty that had sprung from his great mind.

He sought students to come under his wing, to extract what treasures they could from the vast storehouse of raw knowledge now under his command. Pachmeny was brilliant, but like a star in a galaxy of other stars, who could measure her worth? Others appeared to shine brighter, and perhaps they were.

Or perhaps they had merely flown higher by being launched from a greater peak. Pachmeny’s family were not poor but nor were they notably wealthy, mere ordinary merchants in one of the lesser clans. So Pachmeny had been educated, but not in one of the greater schools; nor had she been taught by the greater tutors, whose brightest students were the most eagerly sought.

But still she had done well enough to be seen, so now she found herself in her little domain, on her little project, delighted beneath her grumbling. She did not really compare herself to others, except perhaps in her darker moments when she wondered what justice there was in the Universe. Then she would remember that there was none; that if she sought justice, it would have to come from people. She would have to earn it. Even then, the justice might not come, but at least the fault would be theirs for failing to see, not hers for failing to try or do.

One of Shemsak’s diverse interests was variable stars. Pachmeny’s project was to refine the analytical engine which pored over the images with a speed and precision no mere mortal human could match. But nor could it match the judgement of those mortals. There were many sources of variation between the images: asteroids, meteors and comets crossing the heavens at speeds from a crawl to a flash; clouds or even flying things dimming images; eclipses by planets or moons; and the optical correction that made the whole thing possible could not be perfect, as distortions of the air were not uniform. Pachmeny’s task was to divine signatures of the different distortions so that they could be excluded from the analysis, or perhaps shunted to other departments whose interests they might pique. Once perfected, if indeed that were possible, the machine could then work its tireless magic hour after hour, day after day, offering up to its masters only those gems worthy of the attention of their august minds.

Human flesh was not so tireless, and Pachmeny stretched, yawned and rubbed her eyes. A grumble from her middle told her that she was hungry as well as tired, and she was tempted to ignore the flashing light indicating an analytical anomaly. Just one more, Pachmeny. Then dinner, a show and party all night.

The Esteemed Shemsak’s fame had bought him five-image series from many parts of the sky, on the theory that five would simultaneously help them weed out spurious differences while giving better data on true variations. So now Pachmeny called up the five different views of the tiny area the analytical engine had flagged, running them in a loop to help her eyes spot and evaluate the pattern.

Curious, very curious, she thought. There were two objects, each a bright point of white, very close to each other and engaged in some kind of slow cosmic dance. The tags noted that these particular stars had never been catalogued. That was not surprising: they were so dim that until this technology had been developed it was unlikely anyone would have noticed them, especially when their backdrop was an arm of the galaxy teeming with anonymous pinpoints of light, many far brighter to the eye than these.

I dub thee Pachmeny’s Stars, she thought, amused at the notion that anybody outside the rarefied atmosphere of astrophysics would ever hear her name, let alone the name of her stars. Then she frowned. There was something odd about the pair, something she couldn’t quite put her finger one, and she leant back to think about it.

Her specialty was not stellar dynamics, but she was sure there was something wrong with what she was seeing. Her eyes widened at the thought of what it was and what the answer might be; but she could not be certain. She had to take this to Shemsak, but she would prefer to give him a story she could be more certain of.

She wasn’t an expert in dynamics but she knew someone who was, and the grumbling in her stomach changed to a tingling somewhat further down when she thought of him. He was another student, a few years older than her, several miles above her in reputation. And while his habits were not rigid, he was not one of those obsessed people who would work without eating: to the contrary, he knew that his ability to think fell rapidly when he was hungry. So at this time of night he was usually to be found in the precinct cafeteria.

Two rats with one rock, she thought happily, rising from her chair.