A vastership is an unofficial classification of spaceship throughout Ealdremen; unlike the majority of conventional spaceships, a vastership is never meant to dock at any solid surface, even that of a natural satellite such as a moon, once it first leaves orbit. So enormous are these ships that they are prohibitively expensive to finance even a maiden voyage, let alone routine stops on planets or moons. Not only do they require more fuel than other spaceships, the equipment needed to launch one from a typical spaceport is rarely used and difficult to maintain, and vasterships must stop at stations where gravity is weak enough that they can disembark, refuel, and make repairs without needing to "fully" dock. As such, it is often said that vasterships are more common in fiction than they are in reality, and those that still fly the stars are typically owned by a collective group of some kind, such as the Miouran diaspora aboard the vastership 09-MRA al-Ariazd. This is in contrast to how vasterships will usually be owned by a single wealthy individual in media portrayals, often one who is using their wealth to cover up sinister secrets aboard the ship; in truth, it is speculated that a vastership is so inconvenient that even the most eccentric of trade tycoons would balk at the idea, and, instead, only insular communities, communes, cults, and other similarly social groups and cultures will be drawn to the true isolation that vasterships can provide.
Because a vastership will almost never return to solid ground, they are meant to be mostly self-sustaining not only in food production, water treatment, and in other facilities, but in having their own populations and "micro-cultures" aboard the ship. Most commonly, vasterships will bring aboard new "citizens" who provide some sort of useful skill to the continued survival of the vastership's people, or they might charge a fee of some kind to be welcomed aboard, and that income in turn is used to maintain the ship at various satellite or station ports throughout the system.
Vasterships typically do not have any true "destination" in mind. They have intricate routes throughout Ealdremen — sometimes even specifically chosen to observe interstellar phenomena — but never stop at any one place for long. They are transitory by nature, sometimes likened to migratory animals found throughout Ealdremen's various planets, and their closed-off nature means that it is rare for outsiders to ever truly know what it is like aboard a vastership.