The Solaris line was the Moon Communes' great dream: a vast network of starship lines that would stretch spinwards across the galaxy, linking inhabited worlds together as humankind spread between the stars. The Solaris line was to be the modern equivalent of the old high-speed lines that dotted Terran continents -- and in the Moon Communes' collective mind, it would one day cover the entirety of the Milky Way, becoming the interstitial tissue of human civilisation. A civilisation at the center of which would be the Moon, not the Earth. One million relays, one hundred thousand passenger vessels -- such was the great plan outlined in the depths of Selene. If it did not have the resources, nor the demographics, to spearhead human colonisation, at least the communal confederacy could master its backstage logistics.

The Solaris Line was the first attempt at building a comprehensive interstellar transportation network. The Moon Communes quickly understood that the key to such an endeavour wasn't the ships, but the lines themselves -- and in space this meant the invisible pathways created by optimal translation trajectories. The Moon Communes thus determined that the best location for relay stations was in the vicinity of variable stars, in order to maximize the accuracy of distance measurements from one station to the other.

Thus were born the Solaris Relays. These deep space ring stations were positioned every hundred lightyears alongside the stellar routes covered by the Solaris Lines, computing geometry translations in real time, based on constantly updated astronomical data. Decorated in the Moon's signature Art Deco style, these stations quickly became a familiar sight for interstellar passengers, their stained glass panels casting colorful shadows on the travellers as they moved from ship to ship while they crossed the vast, cold expanses of the galaxy. In less than two decades, the Solaris Line linked the Earth to Elora, Smyrnia, Okean and even the Serene Sea. For a short while, lunar interests behind the Solaris Line held considerable power in human space.

It did not last.

Seeing the Solaris Line as a threat to their own deep space transportation syndicates, the USRE and Laniakea banded together to sever the Line's connections to the Moon Communes and deployed a delicate mixture of new anti-trust regulations, targeted sabotage campaigns and occult financing of Traverse-bound transportation syndicates; all of which ended up turning Lunar opinion against continued support to the Line. Three decades after its foundation, the Solaris Line was abandoned by its original creators and became an independent cooperative -- still powerful, but unable and unwilling to follow the original intent of its creators. The Line reorganized itself in the following years, abandoning its outermost tendrils to focus on Solar System - Traverse line. To most denizens of human space, this is the full extent of the Solaris Line.

Outer stars dwellers know different. In the Smyrnian Bubble, they can see the derelicts of Art Deco relays, left cold in high orbit of isolated stars, often turned into hideouts for pirates and mercenaries. In the Serene Sea, Algorab has turned the Solaris stations into the armoured nests of watchful AIs, their telescopes aimed at the faint signatures of Sequence warfleets.

And somewhere, high above the galactic plane, a single station drifts in the void only lit by the eerie light of a white dwarf, a trail of stained glass in its wake. Glimpses of heat and light can be seen in the dead hallways, emitted by the three cores of an abandoned AI dubbing itself the Railway Operator.

It watches. Silently. It has ideas and dreams for the Solaris Line -- the ghost part, the forgotten part.

Illustration: Shutterstock.