资源环境科技发展态势分析平台

We report the first extraterrestrial observation of traveling ionospheric disturbances (TIDs) in the ionosphere of Mars (below approximate to 160 km) by NASA's Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. TIDs are ionospheric waves manifesting as an oscillation in density, velocity, and composition of ionospheric plasma. The TIDs were encountered in the Martian dynamo region, where ions are collisionally bound to the neutral thermosphere but electrons remain frozen in to the local magnetic field. The underlying physical mechanism for the periodic ionospheric waves appears to be a bulk motion of the entire ionosphere driven by atmospheric gravity waves in the surrounding thermosphere which have propagated upward from the lower atmosphere. Magnetic perturbations were observed in association with the TIDs, which we attribute to electromagnetic induction from the bulk motion of the ionosphere. We thus demonstrate that atmospheric disturbances near the surface of Mars can propagate upward through the entire thickness of the atmosphere and drive ionospheric perturbations at spacecraft altitudes.