suppermariobroth:

Top: an unused planet found in the data of Super Mario Galaxy, called “PlanetDisk” in the file system. Note the three trees and three raised platforms.

Bottom: the official Prima guide for the game includes many pieces of concept art. Among them is an extremely tiny sketch of a planet that, due to its three trees and three platforms, appears to be PlanetDisk.

_{Main Blog | Twitter | Patreon | Store | Sources: see bottom of both images}