Deletion of evidence
According to new research, acidic liquids may have long destroyed evidence of past biological life inside the March clay – possibly explaining why it has been so difficult to find evidence of ancient life on the red planet.
Cornell and European researchers claim that new experiments described in a paper published today in Nature journal Scientific reports, shows that such liquids could place severe limitations on the ability to find evidence of early life on the planet’s surface.
Scientists have long targeted Martian bearings to collect samples, as they could protect any organic material inside.
“We know that acidic liquids have previously floated on the surface of Mars and altered the clay and its ability to protect organic matter,”
Without a trace
In a series of experiments, the team simulated the Martian surface conditions inside a laboratory. Their goal was to preserve a specific amino acid called glycine inside clay samples. These clay samples had previously been exposed to acidic liquids that simulated planetary conditions.
“We used glycine because it could degrade quickly under the planet’s environmental conditions,” Fairén said. “It’s perfect informant to tell us what was going on inside our experiments.”
After administration of ultraviolet radiation, the glycine molecules are broken down inside the clays.
“When clay is exposed to acidic liquids, the layers collapse and the organic material cannot be preserved,” Fairén explained. “They are destroyed.”
“Our findings in this paper explain why searching for organic compounds on Mars is so difficult,” he added.
READ MORE: Study shows difficulty finding evidence of life on Mars [Cornell University]
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