Seasonal Dependence of Discrete Aurora and Magnetic Reconnection at Mars

A substantial number of discrete auroral events that populate the Martian crustal fields have been detected by the Imaging UltraViolet Spectrograph (IUVS) onboard the MAVEN spacecraft, as reported in Johnston et al. (2023). The IUVS nadir observations reported in that study revealed a regional and local time dependence of discrete auroral events. The opposite polarity of the northern and southern regions of the Martian crustal fields produces discrete aurora before and after midnight respectively due to reconnection that arises from the opposing orientation of the interplanetary magnetic field in each region.
Now that a regional and local time dependence has been established, the natural extension of this work is the investigation of the Martian seasonal dependence of discrete aurora and the associated magnetic reconnection. The orientation of Mars’ axis with respect to the solar wind may influence the magnetic reconnection probability which may result in discrete aurora over the crustal fields. This work will build off that of Johnston et al. (2023) by investigating their reported discrete auroral events paired with the interplanetary field orientation and the Martian seasons. Furthermore, we will highlight recent IUVS nadir observations and expand the analysis with an estimate of 50% more data and confirm the influence of Martian seasons on discrete auroral events and reconnection at Mars.