High resolution observations of linear polarization of the 6818.8 Å feature of methane for Uranus and Saturn

Observations of the linear polarization in the fully resolved 6818.8 Å feature of CH₄ in Saturn and Uranus show dramatic changes of linear polarization across the line profile. The change in position angle of polarization across the line core, especially for Saturn, indicates a likely Rayleigh scattering origin for the observed polarization.