Abstract: A flexible sheet can be stored or patterned while in a flat configuration, and subsequently readily adapted to overlay a curved surface, for example a hemisphere of a sphere. Radial incisions made to the sheet provide a hub and a plurality of substantially triangular gores that adapt the sheet to conform substantially to the curved surface. A patternable transparent cover, adapted to be removably and/or pivotally secured to the hemisphere, closely overlays the sheet to form a covering assembly. Covering assemblies may be placed over one or both hemispheres of a sphere and fixedly or removably joined together.