A study published this week in Nature provides a new explanation for how clay formed on Mars, which could help scientists and engineers figure out how to unlock the early climate history of the planet.
Kevin Cannon, a postdoctoral researcher at the University of Central Florida who led the research while completing his Ph.D. at Brown University, notes that the basic recipe for making clay is to take rock and add heat and water.
He adds that the same material used for ceramics and pottery on Earth is also found on Mars, "and now we think it may have formed beneath a thick steamy atmosphere just after the planet formed."
There are thousands of clay outcrops on the Martian surface and more buried underground.
This kind of clay is formed by the interaction of water with volcanic rock, leading many scientists to conclude there must have been widespread surface water or an active hydrothermal system at some point in Martian history.
But the new research suggests the clays formed during the creation of the Martian crust itself, long before any water could have flowed on the planet.
The scattering of the clay would be the result of impacts on the Red planet years after its initial formation.
Cannon and his co-authors said the scenario offers a means of creating widespread clay deposits that doesn't require a warm and wet climate or a sustained hydrothermal system on early Mars.
To test his theory, Cannon and his team recreated the conditions of early Mars in a lab at Brown.
They used synthetic Mars basalt, high temperatures and pressure vessels to see what would happen.
Cannon says a combination of lab experiments and computer modeling support the new theory.
By better understanding the formation of the clay and its evolution over time, researchers will have more clues in figuring out the earliest history of Mars and potentially other planets, Cannon says.