Asulo was its name. A small rocky planet with an oxygen/nitrogen atmosphere, it orbited a yellow star at that magical range that allowed for life to sprout from the ground and flourish with ease. Far removed from the affairs that dominated galactic affairs, including the borders of any advanced interstellar empire, it was an isolated little slice of paradise in an otherwise cold region of the galaxy.
Upon its surface a small colony was growing. The (somewhat) nomadic Kentauroi had once again decided to settle for a time on solid ground, as they tended to do every few decades when the younger generations grew to power and grew tired with life aboard their cityship. After a while of course, they would grow tired of remaining in one place for too long instead, and would re-board their orbiting home and fly off to nowhere in particular, but for now - they called Asulo home.
And of all the planets they had called home, for their millennia of wanderings, Asulo was perhaps the most lovely. Unspoiled by intelligent life, it was possessed of a largely temperate climate, with the exception of the equatorial and polar regions, and populated primarily by vegetation and herbivores, with few large predators. Mountain ranges did exist on some of the continents, but rolling plains and thick, lush forests tended to be the order of the day, and an occasional midnight rain ensured that the green remained rich. For many people, the nature-loving Kentauroi in particular, it could be considered perfect.
The Kentauroi were doing their best not to damage that, too. While in orbit of the world was a hyper-advanced ship so large that their entire population could reside aboard in supreme comfort, their colony on the surface was comparatively primitive. Their numerous, growing towns were constructed entire of natural materials that they could find growing around them, their food was all grown on the new farms they had set up some distance away, and there was no sign of infrastructure such as electrical grids or sewage systems. The past colonies of the Kentauroi took many forms, but this was certainly the most rustic.
Indeed, only their moderately-sized cruiser, which lay several miles from their city, one of many which still remained aboard their mothership above, provided any evidence that they were actually a highly technologically advanced society. But aside from its subspace transceiver array and its sensor pallet, both of which were required in order to keep in contact with their automated home above and to keep an eye on their surroundings, it was thoroughly dormant. On a daily basis, a citizen of the nearby capital town took a turn maintaining a shift aboard the cruiser, to keep an eye on its systems.
Typically, a boring job. Until today. Dianthe hated her turns aboard the cruiser, but she had been repeatedly told that it was necessary. That didn't negate the sense of boredom, nor the claustrophobia she suffered from its dimly lit, highly spartan interior. But when a transmission arrived, the first since their arrival on Asulo, followed by bizarre sensor readings several hundred lightyears away, she began to understand why it was necessary.
The sensors showed that... something had appeared near the edge of the galaxy. Whatever it was, it was huge, and followed by a simple signal, distributed in many languages - "You have two solar days to leave your planet." It did not appear to be directed at anybody, and its signal strength was immense, but Dianthe felt a sickening sensation in her stomach when she saw that it came attached with coordinates; coordinates which pointed directly at Asulo.
***
Entering the officially-recognised border of the Milky Way, after a vast journey across intergalactic space, the large object maintained a steady course towards the isolated world known as Asulo. It appeared to be moving under its own steam, but it was unusually featureless. A perfectly smooth (so smooth that even the most powerful of sensors could not detect any imperfections) shell formed an irregularly-shaped spheroid that measured well over two hundred kilometres in diameter from its most distant points. Sensors could not penetrate this dull brown shell, and there appeared to be no form of openings or doors anywhere on its surface, at least none that could be seen or detected. There did not even appear to be engine nacelles or weapons emplacements of any kind; just a vast, smooth, featureless shell.
It maintained a steady speed towards Asulo. Assuming it did not change its speed, it would arrive in just over two Earth Standard days. What would transpire when it did, was not clear.
