A STUDY OF THE REFLECTION AND POLARIZATION CHARACTERISTICS OF SELECTED NATURAL AND ARTIFICIAL SURFACES
GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV
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Two aspects of the short wave regime of planetary radiation are considered. Extensive measurements of the reflection properties of a number of surfaces have been made, both the directional reflectance and the degree of polarization of the reflected radiation having been determined. Most surfaces show pronounced limb-brightening for large angles of incidence, while for small angles of incidence the reflectance does not vary greatly with angle at which the surface is viewed. The degree of polarization shows a characteristic pattern for most surfaces, a maximum being located in the principal plane at 100 to 120 degrees from the antisource direction and a small region of negative polarization being observed in the vicinity of the antisource direction. For most surfaces the reflectance increases and the maximum degree of polarization decreases with increasing wavelength. The reflectance values are introduced into the theory of radiative transfer to determine the characteristics of the radiation field at high altitudes above the surface. For the cases of clear and slightly turbid atmospheres the surface properties have a strong influence on the contrasts which would be observed from a high altitude vantage point. A possibility of using polarization characteristics to enhance contrasts is demonstrated.