Across the Sea of Stars

21 08 2009

CA-772 Grape OS

"The CA-772 Grape orbital utility pods were plentiful around the space facilities above Fram, proving to be of great use during the Texas crisis.  Pilots found their versatility in their relative simplicity; a primary computer-simulation projected itself upon the inside of the iconic domed cockpit, giving a stark vector-driven interpretation of the outside vacuum and objects.  Pilots appreciated this Spartan representation, with the ability to toggle target rendering of objects via distance in varying levels of overlay.  The Grape itself was powered via solar panels, which fed into the small ion propulsion engine and life support systems.  While not the most comfortable of vehicles, they offered a level of reliability and ruggedness unparalleled over Fram."

It had been almost a month since Mayflower had arrived.

It was a slow process to bring the material down from Wilbur to Charlotte. The ribbon that connected the two was much shorter than those which had been built on Earth; Fram was a smaller world, with less gravity and thus a lesser exit velocity, and possessed a longer rotational period. This meant that it took less than a day for a climber to run the length of the ribbon, compared to the week it took to run the length of the Earth elevators.

We wanted to bring down as much material as we could with our limited number of climbers. This meant that we had to intersperse the payload-laden climbers so as not to stress the cable: the closer our laden climbers were to the Wilbur counterweight, the greater the lean in the cable as coriolis force produced by Fram’s rotation acted upon the mass of the climber. We joked that one day we would not have to worry ourselves with this effect – as with each of our shuttle launches, the ascent of a climber robbed Fram of a fraction of its rotational momentum. At some indeterminate point billions of years in Fram’s future, assuming the space elevator continued to run, Fram’s orbit would slow to a halt.

We were powering the climbers by using the solar farm on the surface, which was not the most efficient method and reduced our capabilities further. Eventually we hoped to power the cable itself, using the conductivity of the carbon nanotube. Plans were drawn up in which the Quoqasi’s fusion plant, now useless, would be moved down to the surface and installed at Charlotte Station.

And so we unpacked Mayflower, day by day shuffling more material down to the surface.

Already Charlotte had grown into a bustling hive of activity, spread over hectares of carbon sheeting. KOVTARs worked at unloading the climbers during the night. In the marshalling yards were pallets filled with new equipment: fixed-wing cargo planes and their associated launch loops, a new generation of integrated tracked-biped walkers, over the horizon radars, hydroponic domes, mining lasers, and more. Most important were the tanks of consumables, twice as tall as a KOVTAR. These were painted according to their contents: blue for oxygen, green for nitrogen, red for deuterium, purple for iodine. Their edges were stencilled with checkers and their faces with the chemical symbol of their contents. These would open up of closed-loop life support systems and give us a redundancy we hadn’t enjoyed since leaving Jupiter, or power the fusion plants for years to come.

While the crew of Port Mayflower worked to unload our supply ship and send this material down to the surface, the Grapes went to work disconnecting components of the Mayflower’s payload. A pair of probes were nestled in the lee of the May’s cargo modules, fore of the drive stack. It had taken a fortnight to safely cut through the remains of its protective sheath of ice and disconnect them from the Mayflower, and another fortnight to perform diagnostic checks of their hardware.

These probes were themselves larger than an orbiter, each the size of a naval cruiser. They were of a similar dark grey to the hull of the orbiters and the Grapes, although sections of the engine were the lighter white-gray of beryllium. The nose of each probe was a cluster of instruments, spectroscopes, enormous optical and radio telescopes, and repeller fields like those which shielded the Quoqasi and Mayflower from the interstellar medium. Buried in the hull behind these were the probes’ central computers, replete with communications systems. Just behind the bulbous nose was a ring of a dozen small spheres, situated at points of the hour on a clock around the probe’s nose. These were sub-probes which would launch from the mother probe once targets had been identified.

The defining feature of each of these probes was the payload stage. Around the midsection of each probe were six spheres, each a hundred and fifty meters in diameter, clustered around the fusion engine like berries on a stalk. Here was the reaction mass which powered the fusion rocket that spurted from the aft of each probe. Three tanks carried deuterium while another three carried helium-3, mined from Europa and Luna respectively.

These probes were designed to travel on from Alpha Centauri, to two more points of light in our sky.

Their targets had been selected long ago, after the decision had been made to colonise Alpha Centauri. Their targets were closer to Fram than they were to Earth, but only just so; sending them to us with the Mayflower hadn’t saved them a great distance. Rather, carried by the Mayflower, they saved reaction mass that could otherwise be spent travelling to their targets faster.

Their targets were a pair of M1 class red dwarfs about three to four times as far from Alpha Centauri as Alpha Centauri was from Earth. We had a number of designations for these stars, depending on whether one ascribed to the Gliese catalogue of nearby stars, or the Bonner Durchmusterung catalogue, or the Draper, or the Hipparchos… Despite these various catalogue designations, we had no names for these stars.

One probe was to be sent to BD +15° 2620, otherwise known as Gl 526; the other to Gl 832, itself also known as HD 204961. These stars were respectively just under seventeen and a half light years and fourteen light years from Fram.

RigelKent03

The probes would cover the distance at much greater speed than had the Quoqasi. Unencumbered by fragile humans and with a bounty of reaction mass upon which to draw, their fusion rockets would propel them at twenty-five gees of acceleration for four weeks. This would take each probe up to .90c – nine tenths the speed of light – a speed at which each would cruise before decelerating by a similar force and for a similar period at the conclusion of its interstellar flight.

At .90c, the probe to BD +15° 2620 would take nineteen years and two months to reach its destination; the probe to Gl 832 would take fifteen years and six months.

These stars were the next closest to Alpha Centauri on the road to a cluster of stars, coreward and trailing of Sol, which showed a good prospect for habitable planets. Surveys conducted from Sol using gravitational microlensing, observations of planetary transits of each star and variations in that star’s spectral lines had detected numerous orbiting gas giants. We knew, for instance, that Gl 832 had a gas giant named Bailey orbiting it at a distance of 3.4 AUs (we had named the planet but not yet its parent star). But our detection methods were limited by distance; the best way to determine if there were habitable, terrestrial planets around BD +15° 2620 and Gl 832  would be to get closer, or better yet, to visit the systems themselves.

The instruments buried in the nose of each probe would make observations of each system throughout its unpowered glide. These observations would be limited once each probe flipped end over end and decelerated; once this manoeuvre was complete, the probe would insert itself in an orbit that would bring it looping into the inner system. At this point the sub-probes would detach, and fire off to orbit and explore points of interest. They would send telemetry back to the mother probe, which would in turn tightbeam its findings back to Fram and to Earth. The most comprehensive of these findings, made while the probes orbited the target stars, wouldn’t reach us for thirty to forty years.

And so, as we continued to unload the materials sent to our colony by Earth, we prepared to send automated probes further on, across the sea of stars.

The Grapes transferred the probes to the orbiters, and the orbiters moved the probes half an AU from Fram before we sent the go order for the onboard computers to light the fusion torches. The workers unloading the latest material sent down from Port Mayflower noticed a new spark in the sky – at length this spark separated into two smaller points, one rushing toward a point eleven degrees down, the other seventeen degrees up, from the plane of the ecliptic…

 

 

A note on the use of the map in this post: this map was created by Winchell Chung of Project Rho, who kindly gave permission for its use to the authors of Orbital Shipyards. Copies of this map are available from Mr. Chung’s Project Rho Productions, and we highly recommend the quality of his work and direct our readers to his website and his store.

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Planetfall +91

29 01 2008

We had already drilled and installed pitons along the length of Wilbur; after we’d guided the Mayflower close to the body, we drew out tethers from her hull and connected them to the pitons. Then – with the ship’s thrusters, our orbiters as tugs, and by tightening the tension in the tethers – we drew the Mayflower in to attach to Wilbur. It took hours, but we didn’t want to compromise the hull or the integrity of Wilbur with our haste and eagerness.

Mayflower was a simply designed ship, even by comparison to the Quoqasi; she had a simple role, and was built to fulfil that role with a rugged reliability. In spreading its achievements to the planets of Sol, humanity had learned to value modular designs above anything sophisticated or specialized. Redundancy, reusability, and mission profiles were crucial; elegance was not. Both Quoqasi and Mayflower embodied this philosophy, although they magnified the scale, as befitted the first of mankind’s leaps across the darkness between stars.

Both ships comprised a drive stack which propelled the mission module – their drive stacks were of the same design and specifications, and in the modular nature of human design, they could thus be called sister ships, or of the same class. But their mission modules were vastly different.

Quoqasi carried a crew of human colonists, and the equipment and materials needed to begin life on another world: it was a colonization ship, composed of four separate colonization pods and all the apparatus needed to ensure their safety.

Mayflower, by contrast, was a supply ship. It required none of the equipment to maintain a crew – life support, complex redundancy navigation computers, communications gear, lifeboats, even sensors. Instead, where the Quoqasi hauled fragile humans and the pods which would begin the first cities in a new stellar system, the Mayflower carried raw payload. With only a pre-programmed course and basic telemetry data relayed from Sol behind it and the Quoqasi light months ahead of it, Mayflower had crossed the dark between Sol and Alpha Centauri alone.

Instead of the colony pods which clustered around the central spine of Quoqasi like berries on a stalk, Mayflower’s stack was enclosed in cargo pallets, serried in rank and level and size. These layers of cargo containers were enclosed by gantries and scaffolding – these were the prefabricated beginnings of Port Mayflower.

When Mayflower was mated to Wilbur, our teams set to work cutting through the last of its ablative hull. Tonnes of ice, formed billions of years ago and a handful of light years away, were cut into rectilinear shapes, and cast aside. Later, when the space elevator was completed, we would lower this ice to the surface, where it would be injected into our closed-loop life support cycles; for now chunks of it formed a shell around the station, and these pieces circled Fram in their own orbits.

Then we began to unfurl the station structure – booms and cranes of scaffolding, which had enfolded the cargo components of the ship like the articulated arms of an insect, began to unfold, extend, and straighten. Mayflower’s hull became the main body of the orbital station, and its fusion engine became the power source. As these gantries unfolded into docking stations, our orbiters were able to put to berth, and the crews went to work pressurizing those sections of the Mayflower which would become the manned areas of the station.

Along with the structure of our orbital shipyards, Mayflower had brought with it a long spool of carbon nanotube, manufacture of which was far beyond our fledgling industrial capabilities. We began the slow process of uncoiling the ribbon from the ventral stack of Port Mayflower to Charlotte Station.

Port Mayflower took shape – facilities carried by the Mayflower blossomed across the surface of Wilbur, and arms extended at right angles from the Mayflower’s spindly hull. These arms formed the flanks of our space docks: the smallest would enclose our orbiters, the largest were the beginnings of drydocks for the construction of the planned systemships.

On the far side of Wilbur’s surface we had planned to dock Quoqasi. The two ships would have been equal in length, and would have bracketed the asteroid with their wiry forms; instead, Quoqasi’s dock was cut to half its length, and the salvaged drive stack berthed here. Somehow, through all the chaos of the last week, we hadn’t let the death of Quoqasi affect us; we had been too busy, too stressed, too worried, and this had distracted us from facing its loss. Now, however, seeing that half-length drydock, and in the absence of existential crises, it all hit home.

We turned our high-gain antenna toward Cassiopeia and transmitted a narrow-band message to Sol, thanking them for sending the Mayflower. We did this as a formality, a tradition – Mayflower had left Jupiter’s orbit five years ago, just after we had in Quoqasi; and any message we sent them today would not be heard by human ears for over four years, nor would we receive a reply for closer to nine. Along with our grief for the loss of Quoqasi was the melancholy that came with the realization that Mayflower was our last physical connection to Home.

We had received our first and only supply ship; there was nothing else to look forward to, no promise to hold out for, no outside influence to pin our hopes on.

Now we were on our own.





Mopping Up

24 01 2008

Quoqasi Cleanup

“…grazing the skies below, the orbital operations to recover debris from the Quoqasi destruction continued as Texas was chased down.  What couldn’t be salvaged was shunted into the atmosphere, to be burned up upon re-entry.  We had come too far to be ambushed later by rogue pieces of dead starship, travelling at a deadly speed…”

We brought six orbiters with us from Sol. Initially we’d only been able to put four in orbit, but once the mining site injected enough quartz, silica, and graphite into our resource pool for us to manufacture ceramic heat tiles, the last two were rushed into service.

Two went after Texas; two went after the decompressed stern of Quoqasi, still in a lateral spin after being sheared from the bow; two went out ahead to meet the Mayflower.

No human eyes had been laid on the Mayflower in five years. She was an automated starship, thrown from Sol three months after our own departure in the Quoqasi – she’d trailed us through the long, cold, interstellar night. We didn’t know what condition she was in, how she had fared through her trip, what her current mass was or how profound the Pioneer Anomaly had been on her voyage – we needed to know these things so that we could shunt her into a perfect orbit.

So the last two days before her arrival were the most hectic they had ever been at mission control. We needed to calculate the May’s orbit, we needed to clear that orbit of pieces of the wrecked Quoqasi, and we needed to slingshot Texas the hell out of NFO for good. No one slept, not even the orbiter crews, which was dangerous and reckless but we had no other choice.

All this was further complicated thirty-two hours before orbital insertion – true to the nature of our existence on Fram to date, all our servers crashed, overloaded by the comms and data traffic between ground-based observation sites, satellites, the labs in the Colonies, and of course our intrepid orbiters. It took two hours to get everything back on line, during which objects in orbit were lost from our screens and the May rocketed ever closer to Fram.

The orbiter crews did as much as they could without telemetry and guidance from the ground. But our plan with Texas had been to use the solid-fuel boosters in concert with the ground-based solar station. During those two hours the station couldn’t track Texas, and we lost precious time and a crucial amount of thrust. Fifteen minutes after our systems came back online, simulations showed what we had feared for five straight days – an eighty-six percent chance of coincidence between the orbit of Texas and the orbit of the Mayflower.

We thought of altering the asteroid’s orbit, if we couldn’t move it completely – a couple of degrees from its current latitude would swing it across Fram’s equator and, eventually, over several weeks, approach a circumpolar orbit. But it was an impermanent solution, made useless by the Mayflower’s own complex orbit: to avoid the ring of Fram, the May – like the Quoqasi had – would graze the atmosphere above the north pole, bleed away the last of its inertia through atmospheric breaking, and slide through its own circumpolar orbit until it could readjust its attitude to match the geostationary orbit of Wilbur, beneath the ring.

So instead we did something we probably should have tried all along, had we been as inventive in the hours after we’d lost the Quoqasi as we were forced to be in the hours before insertion. Counter to all conventional logic, we started manoeuvring Texas lower, down towards Fram, and we put as much force behind it as we could.

Texas hit Fram’s atmosphere at a shallow angle, much shallower than the reentry of our orbiters. It slammed into the thick blanket of carbon dioxide which encircled our world, and started to break up and burn. We were terrified, nervous, anxious – our mainframe had crashed just hours earlier and we were all exhausted and deprived of sleep, so we feared our calculations could be wrong.

But then it happened: the altimeter climbed, confirmations came in from a dozen sources, and everyone in mission control cheered. Texas had skipped from the atmosphere like a stone across a pond, and our computer overlaid a red arc – a course projection – tracing a line from the icon of Texas back up into the ring.

“Sure looks good from up here,” came the disembodied voice from one of the orbiters salvaging Quoqasi. The voice was heavily chopped with static, and harsher syllables were distorted entirely. “Plenty of smoke still across the atmosphere, but I can see the thing rising. God, what a beautiful sight.”

“Amen to that,” replied a joyous capcom, over the shouting.

The Mayflower was in good condition, no worse than Quoqasi had been when it arrived. Its armour of Kuiper ice was largely intact, although pitted on a microscopic level by its passage through the cosmic medium. The orbiters could not immediately identify any weaknesses in this outer hull; most of it would ablate away when the May roared across the pole. We began to redeploy the Texas orbiters to meet the Mayflower – the four orbiters would work in tandem with each other and with the May’s own vernier rockets to guide the cargo ship into its orbit.

At planetfall plus ninety-one, the Colonies stopped. There wasn’t a functioning e-suit still in the racks, an operating vehicle in the garage, nor anybody unable to get outside not clustered around a monitor to watch the televised broadcast of two points of light – one Wilbur and one the Mayflower – draw closer and inevitably together in the sky, until at last they merged and became one source of light…