NASA scientists have discovered a network of cracks on Mars that might have been formed from a mud layer drying more than 3 billion years ago.
The cracks were found on a rock slab called "Old Soaker." The image above shows about 4 feet (1.2 meters) left-to-right. It combines three pictures taken by the Mars Hand Lens Imager (MAHLI) camera on the arm of NASA's Curiosity Mars rover.
The Gale Crater
Curiosity scientists have interpreted rocks enriched in mineral salts, seen in images taken by the Mars rover, as evidence of dried up shallow briny ponds that went through periods of overflowing and drying up.
These were seen in images taken by the rover from the Gale Crater on Mars, which was created by an enormous impact that is thought to have been filled by water and sediment.
Deposits on the stones serve as a watermark for different climates on Mars, the NASA team wrote in a Nature Geoscience paper published yesterday.
The scientists are trying to find out how long transitions between different climates took on Mars.
A NASA blog post says that the "Old Soaker" clue might be the first of many, as Curiosity makes its way towards the "sulfate-bearing unit" region, which is thought to have formed in an even drier environment.
Life on Mars?
"We went to Gale Crater because it preserves this unique record of a changing Mars," lead author William Rapin of Caltech said in the NASA post.
"Understanding when and how the planet's climate started evolving is a piece of another puzzle: When and how long was Mars capable of supporting microbial life at the surface?"