A method for determining the effective surface area of a spent satellite depending on its spatial orientation is suggested on the example of the GLONASS spacecraft (SC). To determine the effective area, a point-set model is considered. The satellite is represented as a set of points uniformly distributed over the SC surface. Then longitude and latitude angles are varied in the system of coordinates rigidly affixed to the SC, and the point set is projected onto the image plane. The contour of the projected set is determined, and its area is calculated. As a result, an approximate dependence of the effective satellite area on two orientation angles is obtained.