Mars’ ancient atmosphere could be trapped in clay
They suggest that while water was present on Mars the liquid could slowly trickle through certain types of rock and set off slow reactions that gradually drew CO2 out of the air and converted it to methane. This form of carbon could be stored for eons in the clay. This schematic shows the gradual alteration of iron rich rocks on Mars when they interact with water that contains CO2 from Mars’ atmosphere. Over several billion years, this process could have stored enough CO2 in the clay surface, in the form of methane, to explain most of the CO2 that went missing from the planet’s early atmosphere.
COURTESY OF THE RESEARCHERS
The researchers applied their knowledge of interactions between rocks and gases on Earth to how similar processes could play out on Mars. The researchers found that the amount of clay covering Mars’ surface could store up to 1.7 bars of CO2, or around 80% the planet’s initial atmosphere. Murray believes that Mars’s missing atmospheric layer could be hidden in plain view.
