Geological formations called hollows on Mercury taken by NASA’s orbital Messenger spacecraft
NASA/JHU APL/CIW
Mercury might have salt glaciers that could create the conditions necessary for life kilometres underground. These rock salts may encircle the entire planet, and could transform our image of Mercury as a barren wasteland.
In space, easy-to-vaporise compounds such as water and salts are called volatiles. Historically, scientists have believed that Mercury largely lacked volatiles because of the extreme temperatures that result from its proximity to the sun and lack of atmosphere. However, in recent decades, they have discovered…