Saturday, 17 December 2011Scientists think they’ve uncovered clues to what life might exist on Mars – from a discovery made right here on Earth.
The team from Oregon State University collected microbes from ice within a lava tube found in the Cascade Mountains in America’s Northwest.
They found the little life forms not only live, but can actually thrive in cold, Mars-like conditions.
Study author Martin Fisk points out that, since temperatures on Mars hardly reach the freezing point, the levels of oxygen levels are lower and liquid water is not present on its surface, the conditions in the lava tubes aren’t as harsh as they are on Mars, though “water is hypothesized to be present in the warmer subsurface of Mars.”
“Although this study does not exactly duplicate what you would find on Mars, it does show that bacteria can live in similar conditions,” Fisk says.
His team found that the microbes’ metabolism, under the Mars-like conduction, is driven by the oxidation of iron from a volcanic mineral called olivine, which was found in the rocks of the lava tube. Olivine is also found on Mars.
When the microbes were placed in a laboratory setting at room temperature with normal oxygen levels, they consumed organic material (sugar) the same way other Earth creatures do.
However, when the researchers took away that organic material, dropped the room temperature to near-freezing and lowered the oxygen levels, they noticed the microbes began to use the iron within olivine as a source of energy.
Within the lava tube, where they’re covered in ice and isolated from the atmosphere, the microbes out-compete oxygen for the iron.
Fisk adds, “We know from direct examination, as well as satellite imagery, that olivine is in Martian rocks, and now we know that olivine can sustain microbial life.” |
Saturday, 17 December 2011
VOA News
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