A new semiempirical model of the peak electron density of the Martian ionosphere

Abstract

Observations of the ionosphere of Mars have now reached a sufficient number to begin discussions on how best to create an empirically based model of its global morphology. Here we use nearly 113,000 values of maximum electron density (Nmax) obtained from 2005 to 2012 by the Mars Advanced Radar for Subsurface and Ionospheric Sounding on board the Mars Express satellite. At the altitude of peak density, photochemical processes dominate over dynamical effects, and thus values of Nmax can be organized using three basic parameters: solar flux, solar zenith angle, and orbital distance. The model can be used retrospectively to provide Nmax values for any date starting in 1965. Forecasts are possible using predicted solar flux values extending to the end of solar cycle 24. Validations using Viking in situ observations and radio occultation measurements from several satellite missions provide encouraging results for a useful semiempirical climatological model. Key Points Mars' peak electron density data used to make semiempirical global model Mars ionosphere model extends from 1964 through 2019 Mars ionospheric model available for upcoming NASA MAVEN mission ©2013. American Geophysical Union. All Rights Reserved.