Mars EXpress: status and recent findings

Mars Express has entered its second decade in orbit in excellent health. The mission extension in 2015-2016 aims at augmenting of the surface coverage by imaging and spectral imaging instruments, continuing monitoring of the climate parameters and their variability, study of the upper atmosphere and its interaction with the solar wind in collaboration with NASA's MAVEN mission. Characterization of geological processes and landforms on Mars on a local-to-regional scale by HRSC camera constrained the martian geological activity in space and time and suggested its episodicity. Six years of spectro-imaging observations by OMEGA allowed correction of the surface albedo for presence of the atmospheric dust and revealed changes associated with the dust storm seasons. Imaging and spectral imaging of the surface shed light on past and present aqueous activity and contributed to the selection of the Mars-2018 landing sites. More than a decade long record of climatological parameters such as temperature, dust loading, water vapor, and ozone abundance was established by SPICAM and PFS spectrometers. Observed variations of HDO/H2O ratio above the subliming North polar cap suggested seasonal fractionation. The distribution of aurora was found to be related to the crustal magnetic field. ASPERA observations of ion escape covering a complete solar cycle revealed important dependences of the atmospheric erosion rate on parameters of the solar wind and EUV flux. Structure of the ionosphere sounded by MARSIS radar and MaRS radio science experiment was found to be significantly affected by the solar activity, crustal magnetic field as well as by influx of meteorite and cometary dust. The new atlas of Phobos based on the HRSC imaging was issued. The talk will give the mission status and review recent science highlights

Mars Express recent findings and future plans

International audienceMars Express remains one of ESA’s most scientifically productive missions whose publication record nowexceeds 1000 papers. Characterization of geological processes on a local-to-regional scale by HRSC, OMEGAand partner experiments on NASA spacecraft has allowed constraining land-forming processes in space and time.Recent results suggest episodic geological activity as well as the presence of large bodies of liquid water in severalprovinces (e.g. Eridania Planum, Terra Chimeria) in the early and middle Amazonian epoch and formation ofvast sedimentary plains north of the Hellas basin. Mars Express observations and experimental teams providedan essential contribution to the selection of the Mars-2020 landing sites. More than a decade-long record ofatmospheric parameters such as temperature, dust loading, water vapor and ozone abundance, water ice and CO2clouds distribution, collected by SPICAM, PFS and OMEGA spectrometers as well as subsequent modeling haveprovided key contributions to our understanding of the martian climate. The ASPERA-3 observations of ionescape covering a complete solar cycle have revealed important dependencies of the atmospheric erosion rate onparameters of the solar wind and EUV flux. Structure of the ionosphere sounded by the MARSIS radar and theMaRS radio science experiment was found to be significantly affected by the solar activity, the crustal magneticfield, as well as by the influx of meteorite and cometary dust. MARSIS and ASPERA-3 observations suggestthat the sunlit ionosphere over the regions with strong crustal fields is denser and extends to higher altitudes ascompared to the regions with no crustal anomalies. The ionospheric plasma expands to higher altitudes where itcontacts with the solar wind plasma. Reconnection of solar magnetic field lines carried by the solar wind withfield lines of crustal origin opens channels through which the ionospheric plasma escapes to space, producingstrong and narrow cavities in the density. The situation is very different on the night side where the ionosphere hasa patchy structure. Such patchy ionizations are observed in the regions where crustal field lines have a dominantvertical component. Through these patches the ionospheric plasma from the dayside penetrates and supplies thenightside ionosphere.Mars Express has fully accomplished its objectives set for 2015-2016. The mission provides unique observationcapabilities amongst the flotilla of spacecraft investigating Mars. The mission has been confirmed till the endof 2018. The science case for the mission extension until the end of 2020 has been submitted. The observationprogram proposed for 2019-2020 includes both augmenting the coverage and extending long-time series, aswell as new elements and potentially new opportunities for discoveries. It will be boosted by collaboration andsynergies with NASA’s MAVEN, ESA-Roscosmos ExoMars-2016 Trace Gas Orbiter and other missions. The talkwill give the mission status, review the recent science highlights, and outline future plans