The Schumann resonance on Mars and the ExoMars mission

Mars has a thin atmosphere composed predominantly of carbon dioxide and a conductive ionosphere, so it can theoretically function as a cavity resonator for ELF waves. The existence of a Martian SR has, however, not yet been measured directly — it rests on numerical models.

FDTD (finite-difference time-domain) simulations predict that the first resonance mode would lie roughly in the range 9-14 Hz depending on the dustiness of the atmosphere (a dusty ionosphere shifts the parameters), and that the resonance has a low quality factor, on the order of Q \approx 2 Toledo Redondo 2017Yang 2006. The models also show a marked day-night asymmetry: the resonance is energetically more pronounced on the night side of the planet, where the conductivity profile of the ionosphere differs from the illuminated side Toledo Redondo 2017.

These predictions were to be tested in practice by the landing platform of the ExoMars mission, whose instruments were to acquire experimental data on the SR at the surface of Mars. Until such measurements confirm the models, the Martian SR remains a subject of active research, not an established fact.