Brace yourself, Mars: we’re sending another robotic visitor your way. The European Space Agency’s (ESA) ExoMars mission – a collaboration between various European nations and the Russian Federation – will see a rover land on Mars some time in 2018 after a nine-month journey. Its objective is to search for signs of microbial life, analyzing drilled Martian geological samples with cutting-edge equipment. There has been a heated debate over where to land the innovative little bot within the ExoMars Landing Site Selection Working Group (LSSWG), but this week the group announced that a preferred target site has been chosen: a low-lying equatorial region named Oxia Planum, as reported by BBC News.
The target area is rich in hydrated minerals that can only have formed through prolonged interaction with liquid water. Although it will require final approval from the top brass at ESA, the LSSWG has confirmed Oxia Planum as the primary candidate.
Two secondary areas, Aram Dorsum and Mawrth Vallis, have also been chosen, which have similar physical characteristics to Oxia Planum, but contain a large, ancient flood channel and even thicker clay deposits, respectively. These sites will only be considered if the project – which has been subjected to considerable changes and delays – cannot be launched in early 2018. If the rover is sent to Mars in 2020, these two secondary landing sites will be easier to reach than Oxia Planum will be by the time it lands in 2021.
Dr Peter Grindrod, a Mars specialist with the UK Space Agency and Birkbeck, University of London, was extremely positive about the final selection of possible landing sites. “Although they all offer something slightly different, there is a common theme of being able to access ancient rocks that show evidence of water, and possibly habitable environments,” he told IFLScience.
The region of the preferred landing sites on Mars. Red represents high elevation, green and blue represent low elevation. Image credit: NASA
This rover’s most novel piece of investigative equipment is its drill, which can reach depths of up to 2 meters (6.6 feet). As has been widely reported, flowing water has been confirmed to be present on Mars, both on the surface and below, raising hopes that simple life forms may be found residing within or nearby these relatively water-rich regions.
However, the Martian atmosphere is much thinner than Earth’s, and the planet does not have a magnetic field like our own; this means that powerful incoming solar radiation bombards the Red Planet’s surface, which could potentially kill microbial life. By drilling beneath the surface, the ExoMars rover hopes to find traces of life protected from the harmful radiation. “It’ll be the first time anything has accessed such a deep region, which is exciting in itself. But we should also be able to learn a lot about the broader picture of Mars’ evolution by understanding the geology of the landing site,” Dr Grindrod said, adding: “Hopefully the views will be spectacular too!”
This mission by the ESA will give NASA’s Curiosity, Spirit and Opportunity rovers a new, European-designed friend – albeit quite a distant one. Curiosity, for example – which recently “tweeted” a tribute to Back To The Future Day – is currently within the Gale Crater, on the other side of the planet from Oxia Planum.
Although ExoMars will be looking for signs of microbial life reliant on water, it will not be allowed to visit so-called “special regions” suspecting of hosting liquid water in case it contaminates it with Earth-borne microbes, as agreed by the Outer Space Treaty of 1967.
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