Mars covered in toxic chemicals that can wipe out living organisms, tests reveal

Discovery has major implications for hunt for alien life on the red planet as it means any evidence is likely to be buried deep underground. By Ian Sample.
Read more: https://www.theguardian.com/science/2017/jul/06/mars-covered-in-toxic-chemicals-that-can-wipe-out-living-organisms-tests-reveal?source=Snapzu