Readers contemplate water on Mars and more
Your letters and comments on the August 18 & September 1, 2018 issue of Science News
Life signs
Scientists estimate that there are roughly 10 billion liters of liquid water beneath a polar glacier on Mars, Lisa Grossman reported in “Mars (probably) has a lake of liquid water” (SN: 8/18/18 & 9/1/18, p. 6).
Some online readers wondered what the detection meant for the possibility of life on the Red Planet.
Grossman wrote about the lake’s implications for life in “What does Mars’ lake mean for the search for life on the Red Planet?” (SN Online: 7/27/18). The ice sheets covering the lake on Mars are roughly –68° Celsius. That’s nearly 30 degrees colder than the coldest environments on Earth in which life can thrive, Grossman found during her reporting. For the water to be liquid at such cold temperatures, it must be extremely salty — too salty for even Earth’s salt-loving microbes. It’s possible, however, that some Martian organisms that flourished when the planet was wetter and warmer could have adapted to the cold, salty environs, researchers say.