Radiation pressure on a spheroidal satellite

The pressure of solar radiation on a spherical balloon satellite is proportional to its cross-sectional area. However, there is evidence to indicate that the PAGEOS satellite has not remained spherical, but is more nearly a prolate spheriod that is rotating about its minor axis. If this is true, the force of solar radiation incident upon its surface must be expressed in terms of the shape of the surface and its orientation to the sun. Furthermore, radiation reflected from the surface of an asphe...