“…It has been hypothesized that the water may have originated from the melting of subsurface ice, the discharge of shallow aquifers, or the deliquescence of regolith salts by atmospheric water vapor (Grimm et al, ; Kannan et al, ; Ojha et al, ). Of course, attempts have been made to confirm the source of the liquid water (Carr et al, ), and sampling locations on Mars have included subsurface regions (Byrne et al, ; Dundas et al, ; Jones et al, ). These subsurface regions can be accessed by drilling or via geological features such as lava tubes, within which the search for Extra‐Terrestrial Genomes can be used to target extant or recently dead life (Ciarletti et al, ), given the limited lifetime of DNA on Earth (~106 years, due to hydrolysis) and on Mars (~107 years, due to self‐radiation) under otherwise protected conditions (Carr et al, ; Hays et al, ).…”