One Story Among Many

Years passed, melting into decades, and many things changed in and around Earth. Updates popped up from time to time as the first Founders crossed major boundaries: first the heliopause, then the end of the Sun's Hill sphere, both arguable boundaries of the Earth System, then the midway point to their destination, receiving a varying amount of public attention. As expected, the subsequent fleets crossing the same boundaries hardly earned a tangential mention. The political, cultural, and scientific situation at home continuously and tumultuously demanded the attention of all, so volatile from the point of view of many little points cruising through the near-vacuum at speeds high enough to slow time. Relatively few thought of them aside from the scientists and engineers keeping a slightly sleepy yet meticulous eye on every fleet in the heavens.

But through time and disinterest, the public never forgot the probes. The first fleet arrived 44 years later, the second only a couple years afterward. Some time after this, their messages met expectant ears, for the first fleet's time of arrival was known to the hour. And suddenly, the project was again aflame, updates pouring in from the probes years after the probes sent them, telling tales of successes and failures big and small, each fleet a case study of its own.

And yet, some stories had yet to unfold. In a parcel of space inky and black, far away from home in time and distance, a smattering of little objects hurtled ever forward. NSI XV, better known by the name of its target, NSI Sienna. Safe behind tattered debris shields, each of these roughly cylindrical crafts appeared both untouched and ancient, grizzled and greenhorn. They had traveled a long way. The leading Founders, barely alive, sensed a certain star system coming. They awakened their similarly dormant siblings, and torpid circuits began to whir again. Their end, or perhaps their beginning, was near.

As they entered the system, the frontmost Founder scanned for the little dot they came for, the planet. Once spotted, they started their urgent calculations, composing the first major decision the machines would have to make alone. They would have to find a way to adjust their trajectories toward their tiny, tiny target.

Not too soon after the thought came action. A stream of plasma shot out the side of the first two Founders, to be followed by the next as they traveled along. Then another shot out, and the first turned off, then on again, finely adjusting their paths to cross that of their precious planet as they approached. When the time was right and the planet was huge in their lenses, they now had to rid themselves of their immense kinetic energy. Their trusty and loyal debris shields, upon which they were reliant for so many years, were ejected at great speed, while a cylindrical casing from the back similarly tore away. Exploding suddenly from behind, a giant white sheet unfurled, then unfurled again, expanding many times its size as it filled with the scant gas loosely bound to the planet. This is a ballute, a device somewhere between a balloon and a parachute, and as it swelled to dwarf the Founder from which it came, it began to pull backward on it. First a tug, soon a mighty force dragging it back, the ballute caught the ever thickening air, still far too scant to count as anything besides a vacuum, if the Founder were not going so fast. Yes, at its relativistic speeds, even this nigh spattering of gas molecules was enough to cause significant drag with a large ballute in tow; appropriately, the ballute might well be the strongest component of the entire Initiative. The planet came closer and the air got thicker, the huge ballute straining under the enormous drag as it heated up, screeching the brakes hard. The Founder's trajectory, once leading clean past the planet and back into interstellar space, began to curl. At its closest approach, the ballute was stressed to near breaking, glowing red hot as the gas roared past it, yanking the Founder back. As the Founder swung away from the planet again, slowed to just barely below escape velocity, the exhausted ballute at last tore away. And behind the first two Founders, only most of the others followed; some failed to deploy, doomed to travel through deep space for eternity, while others flung away with failed ballutes in tow. So close to greatness, they are perhaps lucky to stay in this system, at least.

This first approach, tasked with bleeding off so much energy, undoubtedly would cause the most casualties. The surviving Founders had slowed barely enough to maintain a highly eccentric orbit around their planet. This orbit carried them far away into space, only to return them to the planet in many weeks. All would remain like this for now, save two: Upon the next close approach, they both spat out a second, smaller ballute, slowing the crafts again until they orbited comfortably close in a proper circular path. These two Founders' sensors now focused full-time on the great celestial body they had found. As the data poured in, this is what they saw.

Though telescopes had been pointed here, Sienna had never truly been seen before. It, like all planetary candidates for the NSI, had been studied before the NSI even existed and focused upon with even more rigor during the Initiative's early stages, later becoming one of the lucky few selected for terraforming. Once selected, the chosen planets needed proper names, notwithstanding their astronomical designations. The NSI opened public polls for each planet, providing all they knew about it and with what levels of certainty. Though the names were intended to be by humans, for humans, in truth, nearly all were generated by AI's, and all but the final few were sorted through by artificial intelligences solely. Because the planet had confirmed liquid water and a general reddish hue, many names focused on these, such as Vermilion, while others went for names of ideals, such as Solace. Naming things after mythological figures had become unpopular a long time ago, and names of past or present people, also fairly unpopular at the time, were filtered out due to the NSI calling such names too "deifying." As expected, a great many people submitted joke names, including Marmars, purportedly meaning "ocean Mars" from the Latin word for sea; Hearth, "Earth" with an H in front that did surprisingly well in the naming bracket under the guise of sounding homey; and plenty of jokes regarding bodily functions or variations of the word "Mcplanetface" that the large language models filtered out early. In Sienna's case, at least, the officially chosen name also happened to be a popular choice.

Now in the Founders' lenses, Sienna largely fit what the NSI had concluded about it. It indeed has those oceans so precious, covering just over half its surface and contrasting with the beige land, speckled in red, yellow, dark gray. Often occluding these features, the planet is wrapped thickly in clouds, wearing them like a raggedy shawl around its equator that becomes somewhat thinner toward the poles. The atmosphere itself has oxygen in great proportion —  a most wonderful sign — along with nitrogen and a sizeable fraction of carbon dioxide. As expected, it is considerably larger than Earth: 1.47 times greater in diameter, and thus 3.18 times larger in surface area. The temperature, density, even number of major moons all matched stored data from home.

Such general traits are visible across the cosmos. In judging exoplanets from the Earth System, the NSI put high priority on planets with strong evidence of Earthlike conditions. Some are less important than others; in Sienna's case, its hefty mass and large radius give it a surface gravity of about 1.66 g. Though inconvenient, exhaustive scientific experiments had demonstrated that unmodified Earth life can adapt to such a gravitational strength, and the process of acclimatization in humans could go much faster and more comfortably with medical aid. Others traits are much more important, so much so that a planet lacking more than one of them was instantly disqualified: Abundant liquid water, detectable atmospheric oxygen, an orbit in the habitable zone, a Sunlike star. Sienna has all of these, a huge win for it. However, its sweltering 40 °C (104 °F) temperature poses a serious problem. Planet-wide terraforming unavoidably generates a lot of heat that needs to be radiated to space safely; perhaps helpful on a planet that needs to warm up before settlement. However, Sienna is hotter than Earth, requiring the machines to manage their heat in the already sweltering environment while somehow also bringing the temperature down. Despite this, Sienna had too much to offer, so the NSI accepted it alongside its challenges.

With some weeks of observation, finer traits about Sienna soon came to light in the Founders' processing cores. This phase is a tedious one, yet very suspenseful: There is a very real chance that something mission-killing will be discovered. Perhaps the surface is covered in heavy metals, or maybe it is pocked with active, violent volcanoes, or showering in constant debris, all of which the NSI could not eliminate completely as possibilities. However, with luck, most conditions that came back were easily workable. The crust largely contains silicates and various metals turned into oxides, carbonates, and more. The air pressure measured a mere 1.5 times that of Earth. Its orbital eccentricity, day length, and magnetic field strength all landed within acceptable levels. A weak magnetic field would have been an extremely burdensome obstacle to overcome, but not quite mission-killing; humanity would have to send further missions to induce a magnetic field while the machines maintained little city-states of ecosystems defended from the radiation. Finally, Sienna bore only very small asteroids for moons, meaning that all tides were due to its star; stronger than the Sun's tidal effect on Earth, but weaker than those due to the Moon.

Peering ever deeper into the planet's origin, Sienna had clearly existed far longer than Earth, though not clearly to the Founders, which were not designed to come to such conclusions. They only noted its aged mountains and rain-washed surface, and took special note of its few patches of volcanic activity. However, they did verify one hypothesis for Sienna's oxygen atmosphere that happened to require an advanced planetary age: A constant trickle of oxygen from plentiful water vapor splitting in the upper atmosphere with the hydrogen fleeing to space. Critically, this and other factors brought no evidence for life on the surface, though later machines would have to verify on the surface. Discovering signs of life would end the mission immediately.

With the setting set for the story of NSI Sienna, now only the plot remains.