Signs of the most recent life on Mars may have sprung up from underground. Because they would have been protected from harsh conditions on the surface, such as radiation, pockets of underground water may be where Martian life existed most recently.
Sulphates, made through interaction with briny water, lie all over Mars. As water underground is also briny, this suggested frequent upwellings.
But Joseph Michalski of the Planetary Science Institute in Tucson, Arizona, and colleagues found that most basins, where groundwater would have pooled, are free of sulphates. The deep McLaughlin crater is instead rich in clays and carbonates which also formed through contact with water.
Search those basins
As water bearing these minerals would be more life-friendly than sulphate-rich water, which is more acidic, McLaughlin may be a good place to look for signs of life that pooled there from underground.
"The stuff we see in McLaughlin could have been very good at preserving life and could have been habitable," says Michalski.
He suggests that future Mars missions should search such basins for signs of habitability, such as the organic molecules that NASA's Curiosity Mars rover is currently seeking. "Perhaps we need to re-emphasise and redirect our attention to the subsurface environments," Michalski says.
Horton Newsom at the University of New Mexico at Albuquerque, who was not involved in the new work and who works on Curiosity, thinks the idea sounds reasonable. "Given the low elevation location of McLaughlin crater… it is quite reasonable that it was flooded by deep groundwater."
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.
If you are having a technical problem posting a comment, please contact technical support.
Did Mars hide life in its watery pockets?
This article
Did Mars hide life in its watery pockets?
can be opened in url
http://newsdrafting.blogspot.com/2013/01/did-mars-hide-life-in-its-watery-pockets.html
Did Mars hide life in its watery pockets?
