Exomars: final two sites chosen for rover landing in 2020 mission
The two final sites for the landing of the rover of the 2020 Exomars mission rover on Mars of the European Space Agency (ESA) have been identified.
They are Oxia Planum and Mawrth Vallis: two sites characterized by abundance of water in the past.
A primary technical constraint considered was the fact that the selected landing site be at a suitable low level so that there is sufficient atmosphere to help slow down the module’s parachute descent.
The final sites were selected by experts from the Mars community, with representatives from industry and protagonists of the Exomars mission after a two-day meeting during which the scientific merits of three selected sites, along with a preliminary evaluation of their compliance with engineering constraints were presented.
All of the sites lie just north of the equator, in a region with many channels cutting through from the southern highlands to the northern lowlands. As such, they preserve a rich record of geological history from the planet’s wetter past billions of years ago when Mars hosted more water.
Oxia Planum had already been selected in 2015 for further evaluation. Although not yet complete, the investigation so far suggests that the region where the site is “located” would meet a series of important constraints. The other finalist site, Mawrth Vallis – preferred to the third candidate Aram Dorsum – offers a privileged window into a large period of Martian history that could show the early evolution of the Red Planet’s environment over time.
From now on, the two candidate sites will be studies in the greatest possible detail in order to identify the final landing site. On the scientific side, for example, specific sites where the rover could use its drill to retrieve samples of the Martian soil from below surface will be identified. Moreover, possible traverses it could make covering up to 5 km from its touchdown point in order to reach the maximum number of interesting sites will also be identified.
On the engineering side, teams will continue to map the distribution and sizes of rocks and craters, and to document the angles of local slopes and the coverage of soft ‘sand’ of the selected sites, to ensure the landing and traverses across the planet are as safe as possible.
Around a year before launch, the final decision will be taken on which site will become the landing target. Therefore, we must wait until 2019 to know where the Exomars rover, searching for traces of past life on Mars, will land.
Italy plays a crucial role in this ESA mission on the Red Planet. Italy is responsible for Exomars primary leadership, along with the development of the Schiaparelli module that in 2016 tried to land on the Martian surface, and the 2m “drill” designed to penetrate the Martian soil to retrieve samples and the rover monitoring centre.