From World Wind Wiki
World Wind allows users to view multiple worlds. Although termed world, it would be better termed astronomical object since World Wind can be used to represent any spherical object, be that a planet, moon, star, etc.
 Available worlds
There are two ways of adding Worlds to World Wind. The proper way allows distance measurement, elevation data, multiple imagery and a custom toolbar. The second way simply adds imagery layers to an existing world.
- Included in World Wind:
- Death Star
 Changing worlds
In the World Wind main menu click
File and choose your world from the drop down menu. If the world is just a layer image you must select it from the Layer Manager.
 Creating worlds
It is not exceptionally difficult to create your own world for World Wind. A nice (although a little dated) tutorial on this can be found in the Forums.