In analyzing the Martian meteorite, known as Yamato 000593 (Y000593), NASA researchers -- with the help of Japanese astronomers, who first located the meteorite -- determined the rock to be 1.3 billion years old. Inside the layers of ancient space rock, scientists found tiny "micro-tunnels," as well as little glob-like carbon deposits. The shapes and curves of tunnels suggest they are the product of bio-alterations, textures which are similar to interactions observed between bacteria and basaltic materials on Earth.
Scientists say these tunnels and microscopic textures are evidence of an ancient weathering processes involving water and living microbes. The details of the scientists' analysis were recently published in the February issue of the journal Astrobiology.
“The unique features displayed within the Martian meteorite Yamato 000593 are evidence of aqueous alterations as seen in the clay minerals and the presence of carbonaceous matter associated with the clay phases which show that Mars has been a very active body in its past,” said co-author Everett Gibson.
But scientists say it's nearly impossible to rule out the possibility that the micro tunnels were caused by abiotic mechanisms.
"This is no smoking gun," said Lauren White, lead author of the study. "We can never eliminate the possibility of contamination in any meteorite. But these features are nonetheless interesting and show that further studies of these meteorites should continue.”