New Evidence for a Wet Mars

January 20th, 2013

Image Credit: NASA/JPL-Caltech/Univ. of Arizona

The Red Planet’s early evolution appears to be one that’s water rich, and could have been wet environments to support potential niches for ancient life.

New evidence of a wet underground environment on Mars stems from orbital observations by a NASA spacecraft of the floor of McLaughlin Crater. This feature is 1.4-mile-deep (2.2-kilometer-deep) and is 57 miles (92 kilometers) in diameter.

The crater is providing clues that it once held a lake fed by groundwater.

NASA’s Mars Reconnaissance Orbiter – its High Resolution Imaging Science Experiment (HiRISE) camera and the spacecraft’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) — suggest the formation of the carbonates and clay in a groundwater-fed lake within the closed basin of the crater.

Some researchers propose the crater interior catching the water and the underground zone contributing the water could have been wet environments and potential habitats.

McLaughlin’s crater depth apparently once allowed underground water, which otherwise would have stayed hidden, to flow into the crater’s interior.

McLaughlin lacks large inflow channels, and small channels originating within the crater wall end near a level that could have marked the surface of a lake.

These findings and other related information are published today, in Sunday’s online edition of Nature Geoscience.

A more complex Mars

McLaughlin Crater sits at the low end of a regional slope several hundreds of miles, or kilometers, long on the western side of the Arabia Terra region of Mars.

As on Earth, groundwater-fed lakes are expected to occur at low regional elevations. Therefore, this site would be a good candidate for such a process.

“Taken together, the observations in McLaughlin Crater provide the best evidence for carbonate forming within a lake environment instead of being washed into a crater from outside,” said Joseph Michalski, lead author of the Nature Geoscience paper.

Michalski also is affiliated with the Planetary Science Institute in Tucson, Ariz., and London’s Natural History Museum.

Commenting on the new research, Mars Reconnaissance Orbiter Project Scientist Rich Zurek of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. said: “This new report and others are continuing to reveal a more complex Mars than previously appreciated, with at least some areas more likely to reveal signs of ancient life than others.”

The Mars Reconnaissance Orbiter (MRO) was launched toward the Red Planet in 2005.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., provided and operates CRISM.

The University of Arizona, Tucson, operates the orbiter’s HiRISE camera, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Lockheed Martin Space Systems in Denver built the Mars orbiter.

By Leonard David