DESCRIPTION FOR ONLINE SUPPLEMENTAL MATERIAL

Included here are K0 values in the wavelength channels of the Cassini wide-angle and narrow-angle cameras for various scattering angles. The K0 values are calculated using three models: the best fit model from Ingersoll and Ewald (2010) and the small aggregate and sphere-aggregate solutions of this paper (Gao, Kopparla, Zhang, and Ingersoll 2015). K0 can be used to convert from I/F to Mcol using

I/F = K0*Mcol

where I is the measured radiance, pi*F is the solar irradiance, and Mcol is the particulate column mass abundance. The units of Mcol are [kg] and the units of I/F are [km^2].