Europe picks landing site for its ExoMars 2020 rover

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The European Space Agency (ESA) has chosen the landing site for its ExoMars 2020 rover, a generally flat area with scattered craters dubbed Oxia Palum.

After over 4 years of careful study of HiRISE and more recently CaSSIS images Oxia Planum was chosen because scientists were convinced that its fine grained sediments, deposited during the ancient Noachian epoch were ideally suited for the Exobiology rover. With an enormous catchment area the sediments will have captured organics from a wide variety of environments over a long period of time, including areas where life may have existed. The fine sediments should also be ideal for the ExoMars drill – it aims to get to 2 metres depth.

Remote identification with the Mars Express and Mars Reconnaissance Orbiter Infrared spectrometers shows the presence of clays and other minerals giving clues to its aqueous history. A large group of scientists have been working on proposing, characterising and down selecting the sites, all of which had fascinating aspects, but Oxia Planum is the clear winner on both science and engineering constraints.

Based on my analysis of the last two candidate sites, I would guess that they also picked Oxia Planum because it is less spectacular, flatter, and thus poses less risk. It also means the images from there will be a bit more boring for the ordinary person.



  • wodun

    After over 4 years of careful study of HiRISE and more recently CaSSIS images

    Four years just to pick a landing site for a rover. How many years would it take for site selection of a base or colony? Whether it is Mars or the Moon, the actual work of site selection for a human presence is more complicated and time consuming than people think. I could see it going something like this imaging>robotics>humans>winnowing>base/village/colony

    Robotic missions will take forever without operators being in the cognitive horizon. So, I could see some sort of temporary outpost created on a site that wasn’t selected very carefully. But I think teleoperation from space would be a cheaper option in terms of construction and operations and would be better in the long term for prospecting and site selection of long term bases and eventually colonies, mines, and research stations.

    Space isn’t a race, its a marathon. We need to balance the urge to just do something with a pragmatic view of timelines over the horizon. Whatever is done needs to be flexible enough to change with changes in technology and knowledge.

  • wodun

    Oh, check out the season 2 trailer for Mars,

    Everything was awesome when it was just the priestly scientists but now that dirty commerce has arrived, everything is ruined!

    Anyone who thinks that regular non-government people are going to be allowed to go into space and visit other planets and moons needs to realize there is a significant portion of the scientific community and out society at large that will do everything in their power to stop that from happening.

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