4.5cm meteorite to answer 'how Mars turned to stone'

A meteorite may help explain as to how the Red Planet became a cold, rocky desert after losing its thick, carbon dioxide-rich atmosphere, according to researchers.

The researchers said that the Lafayette meteorite showed carbonation signs - minerals absorb carbon dioxide in a reaction with water, the BBC reported.

The researchers said that carbonation may be the key to understand why Mars lost its protective blanket about 4 billion years ago.

The 4.5cm Lafayette meteorite was found in Indiana, US, in 1931, after plummeting to Earth about 3,000 years ago.

The meteorite formed in Mar’s crust about 1.3 billion years ago, and was thrown out of the surface by a massive impact.

A research team from the Scottish Universities Environmental Research Centre (SUERC) performed microscopic analysis on a section of the rock - borrowed from the Natural History Museum in London - and found that silicate minerals, like olivine and feldspar, had interacted with CO2-rich liquid water to form siderite crystals.

Researchers said that the new finding suggests that liquid water may have present on the Red Planet more recently than believed.

They also said that it represents the first direct proof for carbonation on Mars - and ties in with the finding of carbonates by Nasa’s Curiosity Mars rover.

The study has been published in journal Nature Communications.