reflectivity/aborbtion is more than a percentage value. it's also a hemispherical distribution. if you glued retroreflectors to the surface most of the light wo

reflectivity/aborbtion is more than a percentage value. it's also a hemispherical distribution. if you glued retroreflectors to the surface most of the light would go back in the direction of the sun and thus never hit the surface. Those are probably too costly or bulk for satellites. If specular reflections are the problem they might just apply a more diffuse coating.