Jovian Stratospheric Hazes -- the View from Galileo
K. A. Rages (SPRI / NASA Ames), Galileo Imaging Team
During the E4 orbit in December 1996, Galileo obtained eight images of Jupiter's limb -- at latitudes of 8 N and 60 N, at phase angles of 146 and 157 , and in violet (407 nm) and NIR continuum (756 nm) filters. Stratospheric hazes are present at both latitudes. The hazes at 8 N are more or less uniformly mixed with the gas, as are the hazes at 60 N, 295 W (the location probed at 157 phase angle). However, a discrete haze layer is clearly visible above Jupiter's limb at 60 N, 315 W (the location probed at 146 phase angle). The extinction coefficient of this discrete haze layer decreases by a factor of between 407 nm and 756 nm, indicating that the mean particle size in this layer is m. The discrete layer is at a pressure no higher than mbar. The combined gas/haze single scattering phase function at the point where the atmosphere becomes optically thick (the ``main limb'') varies with latitude, and so far efforts to fit both the violet and NIR filters using a common haze particle size have failed, indicating a change in haze particle properties between the altitudes probed ( mbar in violet and mbar in NIR).