Celestial Sphere is the term for the known world.
a potentially infinite globe of open sky, filled with floating Island Continents, most of these continents orbit near the center of the sphere. The Islands Sometimes follow their own rules of physics as they careen about the Celestial Sphere.
The Nine are the most stable of the continents. they orbit the center in relative uniformity with out major disruptions. travel from Island to Island is achieved by Airships of varying makes and Styles.
there are 39 lesser Islands and possibly hundreds of Asteroids.
among the danger of the ‘Sphere are the Strays.
the Skies are also filled with various creatures both ferocious and benign who have adapted to the world away from land.
It’s rumored that on the outer edges of the sphere you encounter The Gale.