The apparent visual magnitude of objects illuminated by the sun as a function of distance between observer and object. Curve A is for a sphere of 1 meter diameter (see equation 1 in text). Curve B is for the OSO spacecraft assuming an albedo of 0.4, a window transmission of 0.5, a solar cosine of 0.5, and the OSO sails broadside to the observer (Roach, J. R., 1967)
NCAS EDITORS' NOTE: The photocopies of this figure and Figure 4 did not scan legibly. It was necessary to regenerate the figures from scratch.