nice idea...gl

Certainly this is a good image. I read the SBS, and really would suggest turning the bump map down to at least 3, if using 3ds max. At the moment the planet looks a little noisy. Also for the material, I would change the shader from "Blinn" to "Phong" and set the specularity to 22 and the glossiness to 22. This will give a more realistic shine and reflect to the Earth. I don't know what render engine your using, But if your using Vray click the area shadows box and play with the UVW values to soften the transition from night to day. But overall a beautiful image.