NAI-funded astrobiologists have uncovered new evidence that the martian surface was wet and clay-rich prior to 4.2 billion years ago. Their study was published in the journal Earth and Planetary Science Letters and focused on aqueous alterations in the Mars meteorite ALH84001. Using Rubidium-Strontium isotope analyses, the team was able to determine when the alterations occurred and the likely source of the fluids that caused them. The results could shed light on the potential habitability of ancient Mars.