Applying Ground Textures

You can just apply your satellite/aerial texture as one enormous texture map, but there are many problems with this approach:

How to tile large textures onto polygonal regions

Detail Textures / Blending Multiple Ground Textures

Texture Caching and Paging

Rendering Textures with OpenGL

typically, you send texture coordinates with glTexCoord, but this involves some amount of computation or storage w/lookup per vertex