Story highlights
- Analysis of Martian weather seems to support the idea that the planet could be dotted with salty puddles at night
- The finding has "wider implications" for efforts to find evidence of life on Mars, a researcher says
(CNN)It's not going to be enough to slake the thirst of the elusive Mars bunny,
but scientists say new research seems to support the theory that what
looks like a bone-dry red planet during the day could be dotted with
tiny puddles of salty water at night.
Experts
have long thought that a particular kind of salt detected in Martian
soil could pull water vapor from the the planet's thin atmosphere into
the soil at night and then keep it from freezing despite the extreme
cold.
Researchers aren't saying they've
seen direct evidence of brine hiding out in the Martian night. But they
say the new study -- based on a full year of monitoring of temperature
and humidity conditions by the Mars Curiosity rover in Gale Crater --
does seem to bear the theory out.
"Gale
Crater is one of the least likely places on Mars to have conditions for
brines to form, compared to sites at higher latitudes or with more
shading," said Alfred McEwen of the University of Arizona at Tucson, a
co-author of the new report.
"So
if brines can exist there, that strengthens the case they could form
and persist even longer at many other locations," possibly explaining
channels seen on Mars that appear be formed by running water, he said.
Researchers say Mars may once have had an sea as extensive as Earth's Atlantic Ocean, and Curiosity has found evidence of ancient streambeds and a lake on the planet.
The vast majority of that water has been lost to space over the eons, leaving Mars an overwhelmingly dry and inhospitable place.
The
new study doesn't change the picture for life on Mars. The researchers
say the temperatures they measured are too low and water too scarce "to
support terrestrial organisms" (sorry, bunny fans).
But
scientists say evidence of water ice at the planet's poles and now more
evidence toward the theory of widespread brines keeps them hoping
they'll find evidence that life at least once existed there.
"Liquid
water is a requirement for life as we know it, and a target for Mars
exploration missions," lead author Javier Martin-Torres said in a
statement.
"Conditions near the surface
of present-day Mars are hardly favorable for microbial life as we know
it," he said, "but the possibility for liquid brines on Mars has wider
implications for habitability and geological water-related processes."
In other words, we'll keep looking.
