One‐dimensional multispecies magnetohydrodynamic models of the ramside ionosphere of Titan

Abstract

The interaction of the Saturnian magnetosphere with the ionosphere of Titan has much in common with the solar wind interaction with nonmagnetic bodies in general. A one‐dimensional magnetohydrodynamic model was developed, for radial distances of 1.3 ‐ 2 Titan radii ( R T ), to study the dynamics of H 2 CN + , C n H m + ( n,m > 2), C 2 H 5 + and CH 5 + , in the ramside ionosphere of Titan. For the case of a dayside ramside ionosphere (solar zenith angle of 60°) we found that the external magnetospheric plasma interacting with Titan's ionosphere produced a very broad region of ionospheric magnetic field whose peak field strength was ≈ 26 nT. The ionosphere was magnetized well below the ionospheric peak, allowing ionizing Saturnian magnetospheric electrons access to this region. The sources of ionization and the electron temperature profiles incorporated into the model depend on the relative locations of Titan, Saturn, and the Sun. The calculated electron and ion density profiles as well as the magnetic field profile also depend on the relative positions of Titan, Saturn, and the Sun.