NASA's Curiosity rover, currently studying Martian mountains for ancient environmental changes, has zeroed in on wet environments and their evolution over billions of years. The new data indicate that past environment in Mars was supportive of microbial life though the exact time frame is up for debate.
This was mooted by NASA and Los Alamos National Laboratory researchers at the American Geophysical Union meeting in San Francisco.
"There is so much variability in the composition at different elevations, we've hit a jackpot," said John Grotzinger of Caltech in Pasadena, California. His science team presented an update on the mission at the meeting.
Significance Of Boron Content
The claim is gaining weight after the detection of boron in the ancient surface of Mars and researchers are hopeful that the arid planet's ancient climate was indeed habitable.
Boron is a telling signature of evaporated past water on Earth and is found in many arid regions including Death Valley at Nevada-California belt.
This new finding by NASA's Curiosity rover at Mars' Mount Sharp within Gale Crater implies that the ancient groundwater at Mars was liquid and habitable.
This is leading scientists to the conclusion that Mars was conducive for microbial life hundreds of millions of years ago.
"If the boron that we found in calcium sulfate mineral veins on Mars is similar to what we see on Earth, it would indicate that the groundwater of ancient Mars would have been 32-140 degrees Fahrenheit with neutral-to-alkaline ph," said Patrick Gasda of Los Alamos National Laboratory in New Mexico.
Curiosity as a robotic rover has been exploring Gale Crater on Mars and completed 1,590 days since it landed on August 6, 2012.
The scientists expressed views on the composition and variations in minerals and attributed them to conditions under which sediments were formed. One main factor is a movement of groundwater through layers and making changes in the size of ingredients.
The latest updates of Curiosity rover also reported more hematite, boron and clay minerals in the uphill layers where the rover is focused now.
Sedimentary Analysis For Life Conditions
According to Grotzinger, the sedimentary basin is like a chemical reactor where elements get rearranged, new minerals are formed and electrons become redistributed. These reactions on Earth can support life.
Until now, there has been no evidence of Martian life even though Curiosity mission was sent to determine whether Gale Crater area was conducive for microbes' life. This was endorsed by Curiosity Deputy Project Scientist Joy Crisp of NASA's Jet Propulsion Laboratory in Pasadena.
Crisp indicated that the choice of Crater stemmed from the "Mount Sharp" area that offered varied geological layering and access to rocks of different environmental phases in Martian history.
Crucial to the Curiosity mission's was finding an ancient Martian lake environment that was rich in chemical factors supporting life and had the presence of relevant chemical energy.
The clue to ancient conditions that backed life was mineral hematite being replaced by magnetite in rocks suggesting warmer conditions, noted Thomas Bristow of NASA Ames Research Center, Moffett Field.
Regarding the increasing presence of boron, as detected by rover's ChemCam in mineral veins of calcium sulfate, the scientists said Boron is associated with aridity and signals evaporated water.
Scientists see two possibilities for higher boron deposits. One is evaporation of lakes that had a boron-containing deposit. Second must be water-dissolved boron being pulled down to older layers and it accumulating at the fracture-filling veins.