OBSERVATION OF ICME INTERACTION WITH THE MARTIAN IONOSPHERE

Abstract:

Using preliminary data from the MAVEN plasma and magnetic field instruments we observe the interaction between an Interplanetary Coronal Mass Ejection (ICME) event and Mars’ ionospheric environment. The ICME onset is observed on October 17^th 2014 at 23:00, closely coinciding with the arrival of Comet Siding Spring, and is followed by a compression of the magnetosheath and ionosphere. After the apparent passage of the ICME, on October 18^th at 09:00 the magnetosheath drastically expands relative to nominal conditions prior to the ICME arrival. Data availability is only limited during the expansion phase of Mars’ ionospheric environment. These phenomena have been previously observed using MEX data (e.g. Opgenoorth et al., 2013 and Dubini et al., 2009), which also show an increase of ion outflow from the upper atmosphere. We will use MAVEN data, together with its high resolution and magnetic field measurements, to expand upon these results.