The Vera had a saying, that moving through space in a rocket was comparable to traveling the ocean using only a sail. Space travel was excruciatingly slow.
The Vera had been able to evacuate about half of the population of terria only through sheer luck and planning. In a way, the Vera considered the lack of time since the first rock a blessing, as The Veran population had barely had time to recover. The upside to this fact was that there was only slightly more than a million souls on terria at the time. With a population that small, it becomes feasible to evacuate a sizable portion. The second ingredient to the equation would be the importance the Vera placed on space travel. Quite early in their sentience, the Vera placed colonization extremely high on their list of priorities, with the aim of spreading themselves until they were completely unerradicatable. The result of this push upwards was an surplus of ships, available at a moment's notice. These ships were used to evacuate more than half of the Veran population, saving thousands.
Once these ships were in space, however, things became much more difficult. The problem was not getting vera to space, it was keeping them alive once they were there. The Vera did have self-sufficient stations scattered throughout nearby space, but such complexes were huge, much to massive to fit on a rocket escaping orbit. Once these ships reached space, the clock started to tick. Without the benefits of self-sufficiency, the length of time the passengers could remain in space was determined by the resources brought.
This length of time was variable, depending on the situation. Nourishment, though important, was not often the problem. The Vera, being naturally pack hunters, were biologically designed to fast for weeks without food. This was obviously not pleasant, but food was lower on the list of priorities than other resources, though some ships had agricultural units on board. Water was not often an issue either, as most organisms were almost completely water neutral. With a proper distillery, water could be reclaimed for months without major loss. Oxygen usage was of a higher priority than water, though still not of paramount concern. This problem was much more noticeable with agricultural units on board. Due to the carnivorous nature of the Vera, the cells contained within the units were animal, using oxygen and emitting carbon dioxide. This contributed to the oxygen usage, but most organisms used only a percentage of the oxygen drawn into their lungs. Life support was not often constrained by oxygen usage, nor was life support constrained by equipment failure, as repairs could be executed in flight. Maintenance was seldom needed, and promptly done.
No, it was carbon dioxide usage that was the killing factor. In self-reliant stations, the carbon dioxide emissions of the crew and food supply were offset by plant life, utilizing the poisonous gas to fuel their growth, replenishing the oxygen at the same time. This was simply not possible aboard a vessel designed to be as light as possible. For each Vera aboard a given vessel, three agricultural units were required. Agricultural unites were not light, and just the basic source of food would weigh far more than the Vera abarad a given ship. This in itself is manageable, but to offset the oxygen usage of the Vera and their food, there would be almost ten units of plant matter for every unit of animal matter. This would just include a small portion of the total weight, as the system needed to transform waste material to biomatter suitable for use in the agricultural unites would nearly triple the total weight. Summed up, taking the entire ensemble to space every trip would be expensive and impractical. Instead, The Vera refueled basic provisions on stations whenever more supplies were needed. This system worked fine under normal circumstances, but these were not normal circumstances. Due to the vast number of Vera moved to space, there was a bottleneck of self-sustainability. If the pathogen had not caused terria to become uninhabitable, the numbers would have worked out with little to no loss of life.
Things were a little more difficult now.
Many of the self-reliant bases and colonies within a few days travel of terria had already been destroyed. The remaining bases were completely overrun with arrivals, fleeing from terria. The amount of room left for the souls left on the dying planet was very little. Due to the foresight and luck of the Vera, however, Ten colony ships were in the process of construction Three days travel from terria. These ships were in varying stages of construction, the least finished of which could only carry a Half of it's regular crew complement, and could only support a third. Luckily, the construction process prioritized sustainability, resulting in every one of the ten ships being able to support at least a third of their normal complement. The most finished of the colony ships, in fact, was able to support five hundred individuals for ten years, even with no upgrades. These ships, together, could obviously not evacuate the entire remaining population of terria, numbering in the tens of thousands. They could, however, evacuate a small number.
Getting to terria was another matter entirely. Engines were not the top priority in the construction of vessels not expected to be in service for months, and thus many of the engines had yet to be constructed. Each of the colony ships, being largely identical, had eight main engines when completed, the main source of propulsion for the crafts. The ten ships should have, together, had eighty engines between them. Instead, they had forty two. Not only were there relatively few engines for these vessels, they were not equally distributed. Two vessels had less than four engines, while three had seven and eight. The most completed of these ships could easily get to terra orbit in three days under it;s own power, but the least completed ship could hardly maneuver in place. This presented a problem, as several of the colony ships were too unfinished to reach terria alone.
Due to their nature as colony ships, two major factors contributed to solving the propulsion problem. Firstly, the engines were built to provide much more acceleration than the Veran body could withstand. This was for two reasons: One, the Vera did not want to be stranded in the case of engine malfunction, and secondly, colony ships were built to capture and tow asteroids to use for resources. The engines, used at full force without added mass (such as the mass of an asteroid) would instantly kill all Vera aboard. The added power was perfect for moving huge amounts of mass without being severely limited by speed. The second utility that solved the propulsion problem was the fact that the vessels could link together. This was designed to allow the vessels to tow each other in case of malfunction, or in order to salvage. Now, it was being used to drag the unfinished ships to Terria.
With every colony ship linked together, the resulting complex could metaphorically limp to the rescue. The speed was, unfortunately, still significantly less than the engines would theoretically allow. The most obvious limiter of acceleration was eliminated before departure. The plant and animal matter that were to feed and fuel the crew were biological, and thus just as vulnerable to acceleration as the vera themselves. The Vera had long since found a solution to this problem, as this would ordinarily force unmanned craft to limit their acceleration.
To understand the abilities of the plant and animal matter contained in the AU's, one must understand the process to create them. The basic template for the animal matter was the cancerous cells of a large herbivore, the most often hunted prey of the Vera. A dozen cancerous samples from a dozen individuals were taken, and grown in labs. Originally, the process for growing cells in labs had been developed to solve Veran cancer, but it was now used to nurture it. At this point, many logistical problems arose. The most major examples were speed of growth, and cellular fuel. These cells grew fast, being cancerous in origin, but they were not yet fast enough to offset the substantial effort needed to culture them. The second, and more problematic, issue was fueling the cells. Given that the cells were no longer part of a complete creature, and no longer had a digestive system, any glucose and other nutrients added to the Au's would have to be in a pure, refined form. At the time, the only way to produce these sugars was to extract these compounds from the cells of a complete creature, which would completely defeat the purpose of the AU's. The animal matter required a nutrient soup to grow, and there was no way to produce it artificially at the time. This problem was solved with the discovery and modification of the plant tissue used in AU's. Two and a half years into Veran sentience, a extremely fast growing moss was discovered in a mountain rage across the world from the natural continent the Vera inhabited. This moss functioned with Very little oxygen, grew extremely fast, and was remarkably tolerant of laboratory conditions. The most Useful trait of this moss, however, was the nutrient soup it secreted.
This species of moss was used in the plant AU's, producing liquid that had been modified to be compatible with the animal AU's. This roundabout combination had allowed simple light to be converted to sugars that could be processed by the Vera. After years of work, the Vera finally had an artificial source of food.
Unfortunately, this process was not very efficient at first. The moss, having been modified artificially, reproduced much less quickly than its unmodified parent species. It reproduced so much less effectively, in fact, that any contamination of the modified variety with the unmodified variety would result in the modified variety be out reproduced to death. This was not a problem when the two stains were separated, but the new variety grew much slower, resulting in far less efficiency.
The animal matter was not much better at first. The nutrient cocktail produced by the moss was compatible with the animal matter, but only just. The animal matter grew even slower than the plant matter. Taken together, the process was only thirty percent as productive as simple farming.
This was, however, the beginning of a great step forward for the Vera. Before this point, a substantial amount of the efforts of the Vera were directed to the simple chore of farming. This was both necessary and quite difficult, as the Vera needed to farm animals instead of plants. The logistics of this farming style are quite daunting: For each unit of Verran tissue, many units of herbivore tissue were required, and for every unit of herbivore tissue grown, many many units of plant matter were consumed. This process was very energy inefficient, as the energy originating from the sun went through two layers of life before the Vera could feed on it. Energy was lost with every tier.
Despite the inefficiency of farming, there was no other option at first. In order to reach space, infrastructure was required, and to built the required components, infrastructure was required. Vera, in order to accomplish this, had to congregate. In order to feed this high concentration of Vera, Farmiga was required. Because of this, farming, however inefficient, was the way the Vera fed themselves for a year. Despite the even more glacial nature of the AU's at first, they immediately replaced farming, as they were much more sustainable.
After this came the arduous task of breeding the tissue for efficiency. The Vera had learned that Genetic manipulation was a great tool to cause huge changes badly, and that simple controlled breeding was excellent for correcting errors and causing small changes. The large, error-filled change had already been completed: now was time for the long task of correcting those errors.
This process took a long time, and was, in fact, still occurring at the time of the plague. Only a year after the first working AU, the new method of food production was more efficient than normal farming. This trend continued, and resulted in a viable method of food production in space.
When the Veran space age started, the AU's required little modification. The acceleration of the first Veran space vessels were either limited by the crew, or there was no crew, and therefore no need for AU's. As the Space age blossomed, the Vera began to have problems with the AU's and acceleration. Necessarily, when UNmanned ships needed to travel to pick up passengers, AU's were required to be on board to feed the crew. Whenever the ship was unmanned, ships could accelerate and decelerate many times faster, without killing the crew.
The problem was, this force would destroy the AU's.
It was soon clear that a better method of preserving the AU's was required. The Machinery itself was designed to handle extreme acceleration, but the tissue inside would turn into a slush of destroyed cells. This problem stumped the Vera for a time, when they once again gained inspiration from the natural world.
Terria had several major landmasses, grouped to one side of the planet. One of these land masses, due to drift within Terria's mantle, was slowly being moved to the south pole. Due to this position, this landmass was a frozen wasteland for half of the year. The native flora and fauna had adapted quite well to this extreme environment, with adaptations ranging from spores to hibernation to allowing organisms to freeze and then reanimate.
The reanimation of frozen tissue was of paramount interest to the Vera. Frozen tissue would handle the extremes of acceleration many times better than living tissue.
This was, of course, much easier said than done. Luckily, the tissue used in the agricultural units was made of single cells. This fact meant that if a genetic change was made to a single group of cells, those cells would populate the AU. This was completely different than modifying an entire organism, which would require a virus called a super slicer, which would change every cell in a multicellular organism at once, preferably without killing the organism in the process. At the time of the second rock, the Vera were struggling to create a super splicer. The Vera had even had limited success, even to the point of successfully modifying an entire Vera to correct a fatal genetic condition. The core flaw of changing a multicellular organism in this fashion is speed.
The Vera could not change genetic material directly. To accomplish the changes they desired, a virus was used. Due to the reproductive nature of the virus, It was a perfect tool for the job. Viruses, instead of replicating themselves under their own power, inject their own genetic material into a host cell that does replicate under it's own power. The genetic material implants itself into the host's material, and procedes to be read along with the rest of the dna of the host. In some virus's reproductive cycles, the cell becomes so filled with copies of the original virus that it bursts, spreading many more viruses to other cells. It was an interesting fact to the Vera, as this process was likely the source of much of the "Garbage DNA" inside their own cells, but it was even more useful.
A Virus could be used to very efficiently spread new DNA throughout a host. The Virus could not only spread it's own sequence, but the code of whatever change the Vera wished to cause.
Unfortunately, this method causes a plethora of problems. Normally, when a virus manages to penetrate the body of a multicellular most, the body attempts to stop it by whatever means necessary, even self destruction. Usually, this ends in either the destruction of the invading virus and all cells that have turned into factories of the same, or the death of the host, should it fail. The Virus's that the Vera used for this purpose were known to be able to bypass the natural immune system of the Vera, Though the virus would usually kill the host, The Vera had modified the test variety to simple reproduce, and not to destroy any cells. Unfortunately, the natural world does not always respond in a way that would preserve itself.
The virus used in the super spicer project Did not cause any harm to the bodies of the Vera, yet the Veran immune system attempted to destroy it using whatever means necessary. The harmless virus nevertheless cause the Veran body's immune systems to destroy all cells affected. Until every part of the Veran body was either changed or dead, the immune system would reject itself, almost always causing a long and painful death for the host.
Despite these drawbacks, the best super spicer the Vera had ever created had worked eight times. Seven of these times were in a laboratory, on test animals. Three of these animals were completely brain dead afterwards, and five were in varying stages of mental disability.
The remaining surviving test subject was a Vera. The Vera did not usually test new technology on themselves, but this subject was a special case.
The subject was quite young for a Vera, a mere two years old. This Vera had proven to be unusually tolerant to his own immune response, surviving a severe infection that almost always caused death similar to that caused by the super spicer. Unfortunately, This Vera was also host to a fatal genetic mutation, usually quite rare. This mutation caused nervous system failure, including the death of neural tissue near the end of the life of the victim. The affected Vera was going to die within the third year of his life, and was likely going to die sooner rather than later. Due to these extreme and rare circumstances, it was deemed a necessary risk to use the super spicer to repair the error.
The end of this experiment was not a happy one. The test Vera survived, but only by the most basic definitions. The test subject did, indeed, handle the rejection process quite well, but the change left him with extreme, and permanent, brain damage. The Vera used in the experiment had asked to be kept alive in the event of brain damage, in the hopes of having the damage repaired one day in the future. This Vera lived on, but in state nearly vegetative in nature. The Vera was kept alive, but it was the opinion of many that It was an existence not worth living. Only because the subject had expressed otherwise was he kept alive.
Despite the tragic ending, this experiment proved something critical. Not only was the super spicer possible, it was actually done. Unfortunately, the plague happened before the super spicer could become more than a last resort.
Thankfully, the tissue grown in the agricultural units did not require a complete change of all the cells contained. A genetic change to a single cell was enough for the agricultural unit to grow an entire crop. As a result, genetically changing the tissue was completely possible, without utterly destroying them in the process.
A small amount of genetic material from the insects of the south continent was used to enable the tissue used in the agricultural units to be frozen, yet still able to reanimate at a later time. After a period of selective breeding to fine tune the change, a working strain was created.
The result of this laborious process was agricultural tissue that could, when frozen, survive the acceleration required from unmanned vessels. This entire enterprise enabled the colony ships built in solar orbit to reach terria in a much shorter amount of time. With limitations set by biological material, the colony ship group would have taken six days to have reached Terria, with frozen tissue in the agricultural units, it only took two.
The basic plan for the retrieval of survivors from terria was to accelerate for as long as possible without overshooting the shuttles, the decelerate just enough to allow docking. The survivors from terria, of which only a small fraction could be retrieved, would meet with the colony station in the short time it was nearest the planet. After the pickup, the colony ships would, propelled by terria's gravity assist, shoot out into space, detaching as they do did so. This would hopefully save a few lives, while also limiting the possibility of contamination from the foreign threat.
The colony station will arrive in twelve hours. Without the pickup, the survivors of terraria will be doomed to a inevitable death at the hands of an unknown power.
The survivors watch the sky, hoping for survival.