Cassini 2 Coronal mass ejection 2 Electron number densities 2 Impact ionization 2 Ionization 2 Ionosphere 2 Ionospheric electron densities 2 Ionospheric measurement 2 Langmuir probe measurements 2 Magnetosheaths 2 Saturn 2 Solar wind 2 Solar zenith angle 2 Titan 2 electron density 2 ionization 2 ionosphere 2 magnetopause 2 magnetosheath magnetosphere 2 planetary atmosphere 2 probe 2 spacecraft 2 zenith angle 2