Foundation Day

4 11 2011

There was the collective murmur of several hundred excited conversations, competing with the sound of jazz music from the speakers.

“It’s like polarization modulation.”

Stepan Eshkol and Elzette Skovgaard stood together awkwardly, cradling their drinks. Stepan pushed his glasses up his nose and articulated analogies for the clashing sounds of the party, while Elzette watched him discreetly from the corner of her eye. The glimmer in those eyes suggested that she was already abuzz from the kava. She tucked a strand of auburn hair behind her ear.

Jacques Renard slipped past them. He saw Ruslan Rusakov, whose arm was wrapped around the shoulders of Xu Sze Leng, and both were engaged in conversation with Allesandro Mierhof and another colleague whose back was to Jacques. Mierhof was quite animated, speaking loudly and gesturing with his hands. Jacques caught Ruslan’s attention. Jacques gave a smile and a nod, which Ruslan coyly returned. Ruslan mouthed the words: thank you.

The crowd was densest around the bar. Here they served a number of juices, grown on Fram for the first time from seed stocks frozen during the trip on the Quoqasi. There were limited supplies of these first crops, but the occasion merited their enjoyment. There were orange, strawberry, carrot and tomato juices, and these were poured atop ice and shots of kava. Vessels containing sticks of celery flanked the bar.

“I won’t lie to you,” Mierhof exclaimed over the hum of the crowd, “I do miss a good drink. Honest to goodness alcohol. It’s been years!”

Vetsera Lindenmeyr and Leroy Stohlberg wormed their way through the crowd, Vetsera leading and, holding hands, pulling Leroy behind her. They stopped at the bar and Lindenmeyr ordered two drinks; Stohlberg wrapped his arms around her and kissed the back of her neck. They giggled. Both smelled of smoke – a blend of zornia latifolia, pedicularis densiflora, Egyptian water lily and Turkistan mint.

Yi Jianyu and Harlan Zimmerman were speaking with Konrad Faraday, describing the progression of Fram through its orbit in the time since Planetfall.

“Winter is coming,” Yi said. “One Earth year is less than a third of a Fram year.”

He held two fists up to demonstrate the orbit of Fram around Alpha Centauri B.  He described the dropping temperatures as Fram receded from Alpha B. Yi was oblivious to Faraday’s boredom.

Spread across one wall of the cargo bay was a softscreen, on which footage of the Foundation Day festivities was cycling. Disinterested members of the crowd watched this footage. There were gala balls in each of the colonies, and Charles Clarendon and Gina Divero – representing the Presidium – were celebrating on Port Mayflower. Smiling for the cameras, Gina and Clarendon were shaking the hands of Tomasz Borzęcki and Chesney Perrine – both of whom had been named in the Colonial Honours List.

The youngest recipient of that award was in the arms of his mother. Peregrine, with a thin clutch of dark hair, looked upon the ball with curious but tired eyes. He shied away from the most enthusiastic of partygoers, and laid his head on his mother’s shoulder. Sanna Winslow hitched him up on her hip as she spoke with well-wishers.

On the softscreen now was the sombre procession of images of those who had died in the past year: twenty-nine faces, happy and smiling, lives cut short in the accident at the mining site, the loss of the Harry Gold in a solar flare, the depressurisation of Alpha-2, cut short by suicide and by murder. Sanna pointed out the face of her late husband to Peregrine.

Naftali Nassimatissi stepped around the bar. He tapped a spoon to his glass of tomato juice.

“I don’t really have anything prepared,” he began, to a ripple of polite laughter. “We’ve seen tough and we’ve seen wonderful times. We’ve all seen triumph and tragedy. I think what says it best is that, nine months ago, we were enduring rationing – and tonight we have fruit and vegetable juice.”

Applause.

“I’ve heard many people tonight discussing this anniversary, and some saying that we should move away from the Earth calendar. I just want to say that we still call Earth ‘Home.’ I don’t think it’s wrong to celebrate these occasions.”

He raised his glass to the crowd.

“So, here is to our first year on Fram. May there be many, many more.”

“Cheers!”

“Bravo!”

The murmur of the crowd returned, and the Foundation Day celebrations continued into the night…





Convergence, Part Three

3 11 2011

And so, the planetary systems of the two Main Sequence stars of Alpha Centauri came to settle into a tenuous equipoise. Proxima Centauri, Fram, Belgica and Maud, their moons, the asteroids of the inner system and dwarf planets and KBOs of the outer system, circled about Alpha Centauri A and B for four and a half billion years. So too did Alpha Centauri A and B circle about the Milky Way as the entire Galaxy spun like a pinwheel, its spiral arms trailing away from the direction of its rotation. And the Milky Way interacted with the Local Group, and was pulled with the accelerating expansion of the Universe.

It was a stasis of silent, sure, sweeping movements.

In that silence, a narrow and forever imperilled form of life emerged. The impact of comets and carbonaceous chondrite asteroids gave the moon that humans would one day call Amundsen a burgeoning atmosphere, and, with that carbon dioxide, carbon monoxide, methane and ammonia, deposited organic compounds, long-chain hydrocarbons and amino acids. While the planets and moons spun in mean motion resonances, these compounds evolved into a primitive life that consumed carbon dioxide and hydrogen and produced methane.

These methanogens, exceptional and precious and delicate though they were, would never look at the stars and give them names; would never write equations to explain the motion of the planets; would never manipulate the fundamental building blocks of the Universe and use that knowledge to propel themselves across the gulf between stars. For two billion years these methanogens evolved in complexity and function from those cometary hydrocarbons – and then their evolution plateaued, unable to expand from their niche. Fragile fronds caressed the thin air of Amundsen with neither mind nor purpose.

When Amundsen’s surface was shattered by a devastating impact, these methanogens rode debris to the surface of Fram, and, in the overabundance of Fram’s dense carbon dioxide atmosphere, thrived and exploded in numbers.

By contrast, the life that had evolved on Earth was diverse and abundant. It had likewise taken billions of years to evolve, but had done so in an environment of plentiful oxygen, which readily bound with the structural molecules of living organisms – carbohydrates, proteins – and, as an oxidiser, was an energetic component of cellular respiration. Fuelled by oxygen and liquid water, simple cells blossomed over almost four billion years into multi-cellular life; and, in a burst of less than half a billion years, arthropods, fish, plants, and insects appeared; and then, over another 150 million years, reptiles, mammals, birds. After a series of extinction events and periods of climatic change, humans appeared, roughly recognisable after 4.2 billion years of evolution, and certainly within the last 200,000 years as the species that would spread among the stars.

In the space between chords of the musica universalis, humans began to communicate and share knowledge, and to congregate in settlements and farm the lands around them; through agriculture they developed empires and republics and began to speculate about the Universe in which they had evolved. In a flicker of time imperceptible to the patient stars, humans spread across the face of and came to rapidly dominate their planet, first split and then fused the atom, walked on their Moon, developed radio telescopes and studied the stars. As they did so, humans imparted upon the Universe both mind and purpose.

They searched for other worlds like their own. At first they listened to the stars for radio messages, assuming that life had evolved elsewhere as humanity had, and that this life would communicate in the same way that humanity did. They then used increasingly sophisticated technology to monitor the brightness of stars, watching for the transit of planets across the face of those stars; measured the movements of those stars to determine the gravitational influence of large planets upon their star; and, with orbiting space observatories, developed telescopes that could eventually resolve individual planets light years away.

Despite their relative proximity to Sol, Fram and Belgica evaded easy detection. Both were small planets, and many of the methods were biased toward the detection of large gas giants. Belgica orbited close to Alpha Centauri A, and was, at a distance of over four light years, indistinguishable from the light of its parent star. And Fram’s slow, elliptical orbit did not frequently transit the face of Alpha Centauri B – and, when it did, it did so quickly, as Einstein had theorised of an object that moved deeper into the curvature of space-time created by a massive body.

Nonetheless, observations of other stars encouraged humans to believe that small, undetected worlds orbited their nearest neighbours. They sent sophisticated, robotic probes to the closest stars, even as they exploded in number and expanded from their damaged homeworld to colonise the nearest planets and moons of their solar system.

Thus, decelerating from nine-tenths light speed, a robotic mind appeared in the Alpha Centauri system, and reported to the distant minds that had evolved in nearby Sol. This probe noted Fram, noted also its atmosphere and magnetosphere, concluded that human settlement would be possible upon its surface, compiled a report detailing these conclusions to relay to Earth. And with the receipt of those conclusions, two separate star systems – which had, perhaps, in the distant past formed from the same molecular cloud, but which had developed in vastly divergent ways – enjoyed the beginnings of convergence.

Alpha Centauri A and B had not completed two orbits of their mutual barycentre in the time between the arrival of the first, primitive, crackling radio signals from Sol and the arrival of the first interstellar starship. Immediately, the colonists borne from Sol by that ship went to work making Alpha Centauri their home. Intelligence evolved of another star, but an intelligence nonetheless, came to explore and appreciate Fram. Philosophers among those colonists would ask whether Fram had even existed before colonisation, without a sentient, rational mind to observe its orbit, the movement of regolith across the duricrust, the disintegration of Amundsen.

And, then, the life which had come so recently to Alpha Centauri discovered the life that had in so limited a fashion evolved there. At that point, two divergent paths taken by the Universe toward the emergence of complexity, separated by five billion years and four light years, converged…





Emergence, Part Two

2 08 2010

And so, Alpha A and Alpha B grew from T Tauri stars into Main Sequence stars. Their stellar winds weakened. The gas and dust of the protoplanetary disc dispersed as these gentler winds scattered the remnants into interstellar space.

As the dusty veil was brushed aside, a crowded solar system was revealed. Planetesimals without number looped through the system. There were asteroids, small and dark, and planetary embryos, each the size of a small moon. The total matter of more than a dozen Fram masses existed in this period of planetary formation, swimming in eccentric orbits.

Some bodies were drawn together by their mutual gravities, and accreted into larger objects. But many others were accelerated by the revolving, twin stars, or by the weak influence of Proxima, or by interaction with the orbital resonances of larger embryos. When these hastened planetesimals collided, they shattered spectacularly. More planetesimals, laboriously accreted over millions of years, were torn apart by the competing gravities of Alpha Centauri A and Alpha Centauri B.

For tens of millions of years these bodies glided through the system, were agitated by their parent stars, were drawn together or smashed apart. It was chaotic, violent, an interplanetary melee – a dance of mathematics and mass and resonance. Humans would later lend this meaning and call it the musica universalis.

Fram and Belgica grew from this churned belt of debris. They were probably the largest of the planetesimals of the Alpha Centauri system, although they were neither unrivalled nor alone. During the latter part of the first 100 million years of planetary formation, while its orbit was still highly eccentric, Belgica smashed into one of its largest neighbours. The impact was cataclysmic, perhaps the most violent of the system: its outer envelope of mantle and crust was blasted from the core, and the young planet lost much of its mass.

Yet it was this collision which probably bound Belgica to Alpha A. Instead of forming into a moon the way that Amundsen had formed around Fram, the material ejected by the collision crowded about the core of Belgica and collected in the wake of its orbit. This area of dense, ejected material pulled at Belgica with a weak but growing gravity. Over many more millions of years, Belgica’s eccentric orbit was slowed, and it fell into a more circular orbit of Alpha A. After billions of years, this material accreted into the misshapen lump that we now called Maud – Belgica’s smaller twin, trailing sixty degrees behind Belgia’s orbit in the Alpha A-Belgica L5 point.

It was not likely that Fram and Belgica formed around the same star. There was probably insufficient protoplanetary material around each to account for the mass of both planets; moreover, their competing gravities would have profoundly affected the development of both. More likely, Fram formed around Alpha B, and for the first 100 million years it was pounded by impacts as its greater gravity drew in the smaller planetesimals around it.

But not every planetesimal interacted with Fram in such a way as to be drawn toward it. Fram scattered many smaller bodies inward of its orbit, and exchanged angular momentum with these scattered bodies such that its orbit, little by little, was cumulatively drawn outward from Alpha B. Fram’s already eccentric orbit grew into a lengthening parabola that became more pronounced as it scattered more and more objects. After hundreds of millions of years, Fram’s aphelion drew farther and farther from Alpha B, until it began to be affected by the gravity of Alpha A; the aphelion of Fram’s orbit was always drawn toward Alpha A as it too rotated about the system barycentre.

For the next four and a half billion years, Fram’s wobbling orbit scattered other objects orbiting Alpha B. Its gravity distributed thousands of asteroids, comets and planetesimals outward into a sparse scattered disc. It trapped nearby asteroids in its Lagrange points. And Fram captured Sverdrup and Nansen, bound these small asteroids to its gravity well, and made them its moons.

The captured moons became gravitationally tied to Amundsen, and were forced into mean motion resonances. It is not likely that every object captured by Fram’s gravity fell into these resonances; Fram probably once had many more moons, in disordered, elliptical, highly eccentric orbits, which were lost to the gravities of Alpha A and B when they did not fall into resonance with Amundsen.

From this multiplicity of simple interactions, an elegant yet complex pattern emerged.

Through interaction with and ejection by Fram’s gravity well, perhaps ninety percent of the mass remaining after the earliest period of planetary development was pitched outward from the inner system and formed into the scattered disc. Fram’s eccentric orbit oscillated and was smoothed through these interactions, as the system sought to conserve angular momentum. In the absence of gas giants like Jupiter, Fram acted to clear much of the Alpha Centauri system of the remnants of the protoplanetary disc.

Yet Fram was never alone. There was no peak period of bombardment as in the Sol system – impacts were ongoing, a geologically regular occurrence. Fram was weathered by constant bombardment, craters overlaid with craters, mountain systems formed not through tectonic movement but the terrific force of impactors. Carbonaceous chondrites, lost in trans-solar orbits, and cold scattered disc and Oort objects, disrupted from their lonely exile by the passage of Proxima: the impact of these bodies over billions of years gave Fram its thick atmosphere.

Most recent of the large impact events was the collision that created Fram’s ring system. The impact had fractured Amundsen’s crust and pushed the moon beyond its Roche limit. The moon had been disintegrating for millions of years, and would continue to disintegrate for millions more. Tidal stresses continued to break apart the moon and spread its debris into a thickening ring.

The Alpha Centauri system had been shaped for five billion years. Volatile bodies had been distributed into a distant, scattered disc. Silicate asteroids had fallen into Fram’s Lagrange points, or into orbital resonances that kept them far from the planet. The system had fallen into equilibrium, and was as stable as it would ever be; now it was the turn of its recent inhabitants to shape this star system…





Divergence, Part One

7 11 2007

Over five billion years ago, our neighbourhood within the Universe, on the inner rim of the Orion Arm, was filled with a diffuse mist of hydrogen. This hydrogen formed an immense molecular cloud, and light took dozens of our years to cross this cloud. It was a brilliant, beautiful, resplendent stellar nursery – intertwined vespers of gas were lit by the energetic emissions of nearby, second-generation stars, and highlighted by the glare of the nascent Galactic core.

Today we look into the skies and see such giant molecular clouds in the Orion, Carina and Eagle Nebulas.

The molecular cloud which composed our area of the Galaxy was spun by its orbit and by its density into structures: clumps, bubbles, sheets, and filaments of gas orbited with the Galactic disc. The density of the cloud and its low temperature allowed these structures to agglomerate. Slowly, on timescales incomprehensible to the mind of the intelligence which would eventually arise here, these irregularities condensed and the clumps grew. After less than ten million years, gravitational forces began to exceed the pressure pushing outward from the clumps.

We can think of several causes for the molecular cloud to collapse: the cloud could have hit another, equally-dense broth of hydrogen; or, it could have, in its orbit of the Galaxy, passed through a dense region of the spiral arms, crowded by brilliant young stars already blazing into the night. We know, instead, that one of these nearby stars exploded, and that the uneven force of such a shockwave was the catalyst for collapse. We know this because of the presence of heavy elements in the star systems humanity has visited, and studied – gold, uranium, iron, nickel, lithium, and, crucially, carbon; almost everything heavier than hydrogen and helium, the soup of the Big Bang.

It was probably a massive second-generation star, and its death would have been violent and brief. Heavy elements elements could only have been formed inside the nuclear reaction at the heart of this star, or through neutron absorption; in either case, these elements were scattered by the supernova which marked its death. The high-speed impact of this shocked matter into the molecular cloud caused it to lose stability, and it collapsed.

As it collapsed, it fragmented. Chunks of that filament, clumping together into irregular balls, began to separate and disperse. We now call this turbulent fragmentation. The non-uniform velocities within the molecular cloud compressed the gas in shocks as the whole cloud collapsed, forming objects of varying sizes and densities. As these collapsing clumps of matter distinguished themselves from one another, some became gravitationally unstable, and fragmented again, into two or, in the case of Alpha Centauri, three major parts.

From this fragmentation came the material which would compose Sol and its attendant stellar system, the cradle of mankind, and the matter which would form the Alpha Centauri system.

Although these protostars could not yet create nuclear reactions, they did become warmer and thus began to glow brighter. By collapsing and contracting, they converted gravitational energy into kinetic energy – the closer their constituent atoms fell toward the centre of contraction, the less their gravitational energy, which increased those atoms’ thermal kinetic energy. These clumps warmed; as the hydrogen molecules contracted and collided they became excited and emitted radiation in the microwave and infrared spectrums. Much of this burgeoning radiation escaped, in the beginning, but as the contraction continued the molecular density increased, which began to trap these emissions, and a runaway heating effect began.

The protostars grew hot, quickly, and began to glow a dull, cherry red.

Over a hundred million years, the protostars began to spin, flattening the material which surrounded them into a fat circumstellar disc. This material continued to accrete, and would eventually, in billions of years, become the companions to these stars as they orbited the Galaxy – planets, moons, asteroids, and comets. Then, as young stars, Alpha A and B poured out a strong stellar wind. This pushed back the gases of the disc, and matter stopped falling into the star itself.

Parts of the disc began to clump together as had the molecular cloud: no longer falling toward the protostar, the gravitational heating slowed and the disc cooled, and grains of silicates and ice condensed. The grains of metals, water, ammonia, and methane – that 2% of the mass of the disk planted by the detonation which began its collapse – stuck together electrostatically, and as these clumps ploughed through the disc, they slowly grew into planetesimals. Bound together by a static force and a growing, weak gravity, they swam through the hydrogen and helium gases, and distorted the homogeneity of the disc as they orbited the protostars.

In what we would eventually call the Alpha Centauri system, the interactions of the protostars and their circumstellar discs must have been complicated, as are the orbits of the bodies in the system today. The clumping of the disc around each protostar was influenced by the gravity of the other, causing radial lines to spread from each protostar toward their mutual barycentre. These interactions prohibited the formation of the massive Jovian gas giants which grace the Solar system. The beginnings of these gas giants were pulled apart by the competing gravities of the two stars, or were dissipated by their combined stellar winds, leaving only heavy, silicate planets like Fram to form.

Perhaps their discs merged at their edges, and material was swapped between the protostars and the lumps slowly building in their orbit. It is even possible that Alpha A and B were much closer, these billions of years ago, and swam like titans through a shared circumstellar disc, churning the glowing material about in complex tides.

Alpha A and B were spectacular sights, five billion years ago when they were T Tauri protostars. Their surface temperatures would have been similar to what they are now, though they would have been noticeably brighter, as their radii were smaller. Their discs would have glowed red-hot, and would have neatly bisected the stars themselves. From a distance, above or below the plane of the ecliptic, a dome sat at the centre of the disc – a hemisphere that was half a star, surrounded by a wall of slowly spinning matter. The light of the star would throw million kilometre shadows across the matter that was already clumping together in the disc, and ring systems would have developed in that disc as the interactions of the other star perturbed its orbit.

Across the sky, nearby stars were hot and young, filling space with violent stellar winds.

And then, probably within a million years of one another, and over two hundred million years before Sol, each of the twin stars of Alpha Centauri blazed to Main Sequence life.

Deuterium fusion ignition began, pouring out light, heat and radiation. This outflow slowed the collapse, and was channelled by the discs into bipolar streams. This flow imparted the angular momentum of the star to the material of the disc, just as the magnetic fields of their T Tauri stages had – forever, the planets which formed from the protoplanetary discs would orbit their parent stars on an equal plane of the ecliptic, at the equator of that star, and would match the star’s rotation.

Eventually the heat and mass of these stars would be enough to switch from fusing hydrogen to deuterium to fusing into helium instead. Very quickly, nuclear fusion found a balance where the energy exerted from the core balanced the weight of the collapsing matter which composed the star, and gravitational collapse ceased.

Alpha A accreted more mass than Sol, while Alpha B slightly less; Proxima, orbiting far from the barycentre, accreted about an eighth the mass of Sol. The lump of the molecular cloud from which Proxima developed was small, unstable; nuclear fusion in its heart was slow, fusing hydrogen into helium with much less efficiency than the furnaces at the hearts of Sol, Alpha A or Alpha B. It could not easily radiate photons from its core, an instead moved energy to its surface through convection.

Proxima was dim and isolated – it lacked its own circumstellar disc – and from the heart of the growing Alpha Centauri system, it was an insignificant, flaring bead, tracing an arc around the system thirteen thousand times as far away as Earth is from Sol.

Over a billion years, the clumps of silicates, metals, water, ammonia and methane began to build in size. Initially, they were carried by the turbulent motion of the gas disk itself, like debris carried by the swirling, seething motion of a whirlpool stirred by the two stars. When they collided with one another, they clung together, and grew. Soon they grew so large that they developed their own, shallow gravity wells, and attracted one another without the use of the currents foaming about them. Others formed by coalescing in the mid-plane of the disc, where the heavier material collected through the angular momentum of the disc’s rotation, and collapsed not unlike the molecular cloud had thousands of millions of years before.

Protoplanets kilometres across formed in these ways, and glided in languid orbits. And so began a period of intense violence: these planetesimals collided, smashed together, blasted one another apart, coalesced, and, eventually, formed a stellar system recognisable to us today. Close to the Alpha A and B, volatiles like water and methane could not form, and instead bodies of silicates and metals settled into orbits – we now call the largest of these Fram, Belgica and Maud. Both of these planets were created through countless impacts, which imparted mass to their subjects, and altered their orbits. Belgica and Maud found a comfortable orbits close to Alpha A; Fram, its satellites and rings, was hammered, pushed and pulled into a eccentric orbit around Alpha B.

Stellar winds forced the gaseous hydrogen and helium of the disc far from the stars, and icy volatiles which could not form close to the heat and energy of Alpha A and B found stability here also. Thus formed a massive Oort Cloud – trillions of inert lumps of dirty ice, slung from the warm heart of the system by their hyperbolic orbits, or coalesced from the cooled gas, gathered dozens of times further from the barycentre as was Proxima. The Oort Cloud of Alpha Centauri was of much greater mass and density than Sol’s, for here could be found that material of the circumstellar disc which had formed the cores of Jupiter and Saturn, and the entirety of Uranus, Neptune, and the Kuiper Belt around Sol. These objects, while the best source of water for light years, were also the greatest challenge for the Quoqasi to navigate as we decelerated from our interstellar slingshot, and arrived in Alpha Centauri…





Rigel Kentaurus

13 05 2007

Our new home was a world named Fram. It orbited the dimmest of the close binary Alpha Centauri A and Alpha Centauri B. It was one of three planets we had found in the system. Maud and Belgica were small balls of iron that orbited close to Alpha Centauri A, while Fram orbited Alpha Centauri B alone.

Fram was a small world, no larger than Saturn’s moon Titan; Fram possessed a similarly thick atmosphere, although less exotic. An atmosphere of mostly carbon dioxide (65%) and hydrogen (15%), with lesser and trace gases (methane 8%, argon 7%, nitrogen 5%) enshrouded the planet.

The two stars orbited a mutual barycentre, and took just under eighty years to complete orbits of one another. Alpha A and Alpha B at their closest were 11.4 AUs apart, still farther than the distance from Sol to Saturn. At their farthest, they were 36 AUs apart, greater than the orbit of Neptune.

Fram was in a highly elliptical orbit of Alpha Centauri B, which at its perihelion was 0.75 AU from Alpha B; its orbit stretched away toward Alpha Centauri A with an aphelion of 1.3 AU. This looping orbit wobbled with each revolution, as its aphelion was tugged toward Alpha A by the competing gravities of the binary and the rotation of Alpha A around the barycentre. Fram completed an orbit of Alpha Centauri B every three years and five Earth months.

Even at its closest point to Alpha B, less than the distance between Earth and Sol, Fram only skirted the outer edge of Alpha B’s habitable zone. Fram was thus a cold world. When it grazed the HZ around perihelion, Fram’s surface temperature hovered between 5 and 15 degrees Celsius. At aphelion, methane would bond with water ices and would snow from the sky and settle into the craters that pockmarked Fram’s surface; thin sheets of methane and water ice were thus frozen beneath the regolith at the basins of many craters.

Alpha Centauri B was a dim main sequence, orange red dwarf, about eighty-six to ninety percent Sol’s diameter and mass, but only forty-two to fifty-two percent its luminosity. Because of Fram’s elliptical orbit, which was at its closest to the bright Alpha Centauri A when at aphelion to Alpha Centauri B, the planet was at its coldest when the two stars were at their brightest. From Fram, Alpha A appeared to brighten as the two stars approached and dimmed as they receded. Under our e-suits we would wear thermals and coats and scarves.

Much of the matter that, given the stable conditions of Sol, might had agglomerated into large planets had instead been scattered and distributed by the competing gravities of the binary stars; in the Alpha Centauri system there had formed no Jovians, no gas giants, no large terrestrial planets. The entire system was composed of comets and asteroids and lumps of planetesimals too small to form into spherical shapes under their own gravity, all churned about in complex orbits. Fram was the largest of these rich, metallic lumps; it had three satellites that we named Nansen, Sverdrup and Amundsen.

Fram had an extensive ring system, despite being a much smaller world than the magnificent, ringed giants of distant Sol. Its largest moon, Amundsen had been disintegrating for about six million years: struck directly by a planetesimal likely flung by Proxima, Amundsen had shattered and now swam through a complex ring system formed from the debris. It was likely that all of Fram’s ring system had, once, been a part of Amundsen. This ring would, as with the formation of the Moon around Earth, clear in a few billion years, as the deformed remains of Amundsen and the small shepherd moons Nansen and Sverdrup consumed the debris.

But not all of Amundsen had settled so easily into a new orbit. There were strings of fresh craters across the scarred face of Fram, and impact sites across the leading hemispheres of Nansen and Sverdrup. Alarmingly, in the twenty-five years since the first automated probes from Sol had shot through the system at relativistic speeds, a new and massive impact site had formed on Fram’s northern hemisphere.

Fram’s surface had been weathered as had Earth’s Moon by regular impacts for billions of years. But unlike the Moon, Fram had an atmosphere, through which small meteors quickly burned up, and wind and weather fronts and dust storms, which moved the dusty regolith around and disguised all but those enormous craters that had geologically altered the landscape.

Nonetheless, there had been no peak period of bombardment for any of the planets of the system, as there had been in distant Sol; rather, bombardment was a geologically regular occurrence. Impacts from comets had given Fram what little water ice there was on its surface and the lesser gases in its atmosphere.

Fram was a forbidding place. It was cold and dry and its atmosphere poisonous, and yet, a form of life was found here. In the deepest basins of craters and in rilles between uplifted basalt sheets there existed a kind of translucent vegetation – anaerobic methanogens, which sought out the volatile ices frozen here and converted these to methane. It was to these methanogens that Fram owed the methane in its atmosphere.

There was a certain desolate beauty to Fram. At perihelion, Alpha A would disappear for months at a time behind Alpha B, while at aphelion both stars would be opposite one another, and would banish night entirely. Proxima, a flare star, could dramatically brighten and in moments appear as bright as Jupiter from Earth. All three of Fram’s moons could go into eclipse simultaneously, a sight bisected by Fram’s elegant ring. The zodiacal light was bright and intense, even long past sunsets; aurorae filled the night sky, sometimes from two directions, varying in colour; the planet’s ring cast a band of light close to the horizon and divided the hemispheres; and asteroids looped about solar system, brighter than artificial satellites in low-orbit.

From Alpha Centauri, Sol was a bright yellow speck, maybe the magnitude of Capella seen from Earth, far away in the constellation Cassiopeia; and it transformed that constellation’s w shape into a less precise zig-zag…





Aphelion

12 05 2007

The Quoqasi had been decelerating for over two (subjective) years; the ship was inverted, its engines blazing away ahead of it to shed the inertia of its voyage from Sol. Its stem, a clutch of fusion rockets assembled around the central stack, was ablaze with the glow of fusion fire. A fourth sun was suspended in Fram’s sky like a slowly falling star – brighter than the dim red glow of Proxima, but diminished by the brilliance of the two stars which composed Alpha Centauri.

Quoqasi was a skeletal but nonetheless elegant ship, functional and utilitarian, eight kilometres in length. The engine stack, balanced atop the thrust of its three fusion rockets, formed half the ship. Nestled above the exhaust nozzles was the fusion reactor, a voluminous sphere in which helium-3 was fused with deuterium inside electrostatic confinement grids, and thrust thus generated. Feeding into the reactor were payload tanks of heavy water, arranged in a lattice of girders and booms and bunched like berries on a stalk. The engine stack was connected to the mission module by a series of pusher plates – six massive, collapsible, hydro-pneumatic rams suspended within a water/glycol mix and encased within cylinders that clustered the Quoqasi’s midpoint.

Arranged at ninety degree points of the ship’s spine forward of the pneumatic cylinders were four roughly rectangular modules. These were the colonisation pods; small cities designed to split from the Quoqasi and make planetfall independently, each a kilometre in length, each with its own fusion reactor, each crammed with a thousand colonists and their dreams of an adventurous future. These were the basis of humanity’s first extrasolar colony.

Forward of the colony pods was Quoqasi’s prow, a tapered cone that enclosed the central stack. This was where the Quoqasi generated twin repeller fields. The first field reached out a hundred thousand kilometres ahead of the ship and positively charged each particle in its path; these particles would then slide over a second field, ten thousand kilometres from the ship, which repelled anything with a positive charge. As a final measure of protection, a reinforced shield sat like an umbrella held across Quoqasi’s profile against the cosmic medium. Its outer face was reinforced by an ablative covering of ice, tens of meters thick; the entire umbrella was mounted on another suspended pneumatic ram that telescoped back along the spine of the ship.

At high fractions of the speed of light, even microscopic particles possessed tens of kilotons of impact force.

Quoqasi’s average interstellar speed was about .75c: this took into account the slow, uniform, one gee acceleration and deceleration necessitated by its fragile human cargo. During the time in which she had coasted on her inertia alone, Quoqasi greatest velocity was nine-tenths the speed of light. The colony pods were thus designed with a modular, ergonomic architecture – while accelerating, effective gravity was aft; while decelerating, effective gravity was forward; and during turnaround, the habitat section rotated around the ship’s spine, providing centrifugal gravity outwards. Walls and ceilings were as often floors until the pods were comfortably embedded in the duricrust of Fram.

(The journey from Sol to Alpha Centauri had taken just over five years. This was a subjective measurement. Based on an average speed of .75c and a distance of 4.22 light years, five years and seven months passed for the rest of the Universe during Quoqasi’s voyage. For the crew however, only three years and six months had passed – this was the effect of time dilation. At its most profound, at Quoqasi’s greatest velocity, the dilation of time had accounted for two and a quarter days on Earth for each day experienced by the colonists; the average effect of time dilation was, however, more like one point four days subjective to one day relative.)

When the pods were launched, the Quoqasi would remain in geo-synchronous orbit of Fram, gutted of its payload, a slender, gaunt needle in space, awaiting instructions from the ground…