New York: A new analysis of a Martian rock has revealed a record of our planet's climate billions of years ago when water likely washed across its surface and any life that ever formed there might have emerged.
"Minerals within the meteorite hold a snapshot of the planet's ancient chemistry of interactions between water and atmosphere," said Robina Shaheen, project scientist at the University of California.
The meteorite, which fell on Earth 13,000 years ago, was plucked by hunters from an Antarctic ice-field 30 years ago.
Designated ALH84001, it is the oldest meteorite researchers have from Mars - a chunk of solidified magma from a volcano that erupted four billion years ago.
Since then, something liquid, probably water, seeped through pores in the rock and deposited globules of carbonates and other minerals.
"We now have a much deeper and specific insight into the earliest oxygen-water system in the solar system," co-author Mark Thiemens said.
"The question that remains is when did planets, Earth and Mars, get water, and in the case of Mars, where did it go? We've made great progress, but still deep mysteries remain," the authors concluded.
Scientists reported the detailed measurements of minerals within the meteorite in the early online edition of the Proceedings of the National Academy of Sciences.