Water on Mars was surprisingly widespread, long-lasting and perhaps life-friendly
FLOW AND TRAPIt
turns out that certain types of clay minerals are widespread on Mars,
suggesting that water was also widespread — and at life-friendly
temperatures — on the planet early in the solar system’s history,
according to a new study. Pictured is Jezero Crater. The new work
suggests it was a lake as large as Lake Tahoe. Ancient rivers carried
clay-like minerals (shown in green) into the lake, forming the delta.
Rocks (shown in purple) then trapped the clays. The team found evidence
of many such deltas. NASA, JPL, JHUAPL, MSSS, Brown University
Water on Mars was once widespread and long-lasting,
providing environments with the potential to support life, a new study finds.
Previously, scientists had strong evidence that liquid water
chemically altered the Red Planet’s crust at certain times and locations. Those
locations hold the mineral traces of water and preserve in the rock the
planet’s past organic chemistry, says Scott Murchie, co-author of the new paper
published in the July 17 Nature.
Those locations are also “really important” because the
rocks there could hold possible evidence of past life, says Murchie, of the Johns
Hopkins University Applied Physics Laboratory in Laurel, Md. http://louisjjjsheehan.blogspot.com
Using the Compact Reconnaissance Imaging Spectrometer for
Mars, or CRISM, and other instruments aboard NASA’s Mars Reconnaissance Orbiter,
the team looked for specific types of phyllosilicates, or clay-like minerals, that
can form only in the presence of water. The team suggests the water was present
early in the solar system’s history, between 4.6 billion and 3.8 billion years
ago, based on where in the planet’s rocky layers the minerals occur.
Scientists previously identified a few types of these minerals
at about 100 sites, but the sensitivity of CRISM picked up a large variety of the
phyllosilicates at thousands of locations across Mars’ southern highlands. http://louisjjjsheehan.blogspot.com
“Finding all these different water-based minerals at all
these locations really blows the doors off Mars research,” says University of Paris’ Joseph Michalski, a Mars researcher
who was not involved in the study. But, he adds, it all will take years of scientific
study and debate to understand what these sites mean for the history of Mars,
and whether these sites hosted life.
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