Mars could have sustained a habitable oxygen atmosphere more than a billion years before the Earth.
The conclusion was reached by researchers who have been examining both the data recorded by the Mars rovers and the composition of meteorites believed to have come from Mars. While the oxygen on Earth 2.5 billion years ago was most likely a direct result of life, the oxygen on Mars may have instead been created by a chemical process involving water.
"What we have shown is that both meteorites and surface volcanic rocks are consistent with similar origins in the deep interior of Mars, but that the surface rocks come from a more oxygen-rich environment, probably caused by recycling of oxygen-rich materials into the interior," said Dr Bernard Wood.
"Mars' atmosphere could have been rich in oxygen four billion years ago - well before Earth's air became augmented with the gas."
View: Full article | Source: BBC News
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