A NASA spacecraft is providing new evidence of a wet underground environment on Mars that adds to a complex picture of the red planet’s early evolution.
The new information comes from researchers analyzing spectrometer data from NASA’s Mars Reconnaissance Orbiter, which looked down on the floor of McLaughlin Crater (above). The Martian crater is 92 kilometers in diameter and 2.2 kilometers deep. McLaughlin’s depth apparently once allowed underground water, which otherwise would have stayed hidden, to flow into the crater’s interior.
Layered, flat rocks at the bottom of the crater contain carbonate and clay minerals that form in the presence of water. 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.
“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 a new paper on the discovery. Michalski is affiliated with London’s Natural History Museum.