Some salts, like perchlorates, lower the freezing point substantially. It turns out that the temperature for the liquid phase of magnesium perchlorate -- 206 degrees Kelvin -- is a temperature found on Mars at the Phoenix landing site. Based on temperature findings from the Phoenix lander, conditions would allow this perchlorate solution to be present in liquid form for a few hours each day during the summer.
"The window for liquid is very small," Hanley said. Nevertheless, this finding further supports the possibility of finding life on Mars.
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