On the nature of the polarization opposition effect exhibited by Saturn's rings

Abstract

view Abstract Citations (93) References (63) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Nature of the Polarization Opposition Effect Exhibited by Saturn's Rings Mishchenko, Michael I. Abstract The nature of the unusually narrow photometric and polarization opposition effects exhibited by Saturn's A and B rings is examined using a theory and results of laboratory measurements. It is pointed out that the small angular width of both phenomena makes it difficult to explain them on the basis of the commonly used shadowing models. On the other hand, it is known from laboratory experiments and theoretical studies, that a strong and very narrow opposition peak in the reflected intensity can be produced by coherent backscattering of light from powderlike layers of small regolithic grains. Using Ozrin's (1992) rigorous vector theory of coherent backscattering, it is shown that, for subwavelength-sized regolithic particles, the photometric opposition effect is accompanied by a polarization opposition effect of the same angular width. This suggests that the polarization opposition effect of the Saturn's ring has the same origin as the photometric opposition effect and is due to coherent backscattering of light from the regolithic layer composed of the submicrometer-sized ice grains. Publication: The Astrophysical Journal Pub Date: July 1993 DOI: 10.1086/172835 Bibcode: 1993ApJ...411..351M Keywords: Astronomical Photometry; Grain Size; Polarization Characteristics; Radiative Transfer; Regolith; Saturn Rings; Asteroids; Backscattering; Icy Satellites; Light Scattering; Lunar and Planetary Exploration; MINOR PLANETS; PLANETS AND SATELLITES: INDIVIDUAL SATURN; POLARIZATION; RADIATIVE TRANSFER full text sources ADS |