The rock at left, seen by Opportunity rover on Mars, is formed from sulfate-rich sandstone, cemented in the presence of water, scientists say, but this environment likely was not habitable -- due to extreme salinity and acidity of the water. But the rock at right, seen by Curiosity, indicates an ancient habitable environment: neutral pH, chemical gradients that would have created energy for microbes, and a distinctly low salinity, which would have helped metabolism if microorganisms had ever been present. (NASA/JPL-Caltech/Cornell/MSSS)Link
NASA provided this Martian analog to the Yellowknife Bay area, where Curiosity has been exploring. At left, a pit exposing clay-bearing lake sediments, deposited in a basaltic basin in southern Australia. At right is a core sample from the lakebed, with layered, clay-rich sediments. The layers show the changing lake chemistry and environmental conditions over time. (NASA/JPL-Caltech/Ames)Link
Opportunity rover could only abrade the rock, left. Curiosity used its drill to bore the hole at right. (NASA/JPL-Caltech/Cornell/MSSS)Link
The result of the drilling was this scoop of powdered rock, which then provided proof that ancient Mars contained the ingredients for life. (NASA/JPL-Caltech/MSSS)Link
Ancient Mars was so conducive to life that you might have been able to scoop up the water and drink it.
So say NASA scientists, who are thrilled that Curiosity has solved this mystery: Could there have been life on Mars? Yes.
“A fundamental question for this mission is whether Mars could have supported a habitable environment,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program, in a news release. “From what we know now, the answer is yes.”
At a news conference in Washington on Tuesday, mission lead scientist John Grotzinger said signs pointed to an ancient environment “so benign” and “so supportive of life that probably if this water was around and you had been on the planet, you would have been able to drink it.”
The findings come after Curiosity made history by drilling into Martian rock. The rover then scooped a sample of powdered rock and analyzed it with its lab instruments. What scientists found were sulfur, nitrogen, hydrogen, oxygen, phosphorous and carbon — some of the essential ingredients for life on Earth.
The Los Angeles Times’ Amina Khan reported Tuesday:
Hardly a half-mile from Curiosity’s landing site, the Mars scientists say they have already found much of what they were looking to uncover at Mt. Sharp, the 3-mile-high mound in the middle of Gale Crater whose layers may reveal the various chapters of the Red Planet’s geologic history.
Scientists chose Curiosity’s landing site wisely. NASA says data show that Gale Crater’s Yellowknife Bay area was at the end of an ancient river system or a lake bed “that could have provided chemical energy and other favorable conditions for microbes.” And the bedrock where Curiosity drilled showed signs of “multiple periods of wet conditions.”
The only thing that could beat this news? Fossils!
— Amy Hubbard