The ionospheres of Venus and Mars Original Research Article

The ionospheres of Venus and Mars have been explored by a number of spacecraft. It is now widely recognized that. Venus and Mars possess no significant intrinsic magnetic fields, and that the solar wind interacts directly with the upper atmospheres of the planets. The structure and dynamics of the ionospheres are strongly controlled by the solar wind. In situ measurements of Venus and Mars revealed that the ionospheres are often filled with solar wind-induced magnetic field. In addition, the Martian ionosphere is also influenced by the crustal magnetic field at least in some regions, which makes the ionospheric processes at Mars even more complicated than those at Venus. Current understanding of the ionospheric processes of Venus and Mars is presented based on the observational and theoretical studies of the structure, dynamics, and the ionospheric magnetic field of the ionospheres of Venus and Mars.