A Martian meteorite, an incredibly rare object, has been given to science to help unravel the Red Planet's secrets.
Researchers will look for minerals formed in the presence of water, and for any signs of organics - carbon-rich molecules.
Energy, water, a source of carbon are the prerequisites for life as we know it. Finding evidence for any of these phenomena in Tissint tells scientists something about how habitable Mars might have been in the past.
"It's a messenger from Mars," said Prof Andrew Coates from the UCL Mullard Space Science Laboratory. "It allows you to look back at the history of Mars and its formation. It's a history lesson on what Mars' atmosphere was like years ago - could there ever have been the right conditions for life?"
To read the whole article: Rare Martian meteorite given to science