Ever since clay minerals were initially discovered on Mars in 2005, scientists have thought warm and wet conditions which could have possibly supported life may have existed. This is because clay is formed when stone and water interact with one another.
However, researchers analyzing orbiter data from over 350 areas of the planet’s surface have found that the type of clay which is formed underground is abundant on Mars, while the type of clay which is formed above the surface is quite rare. Conditions on the red planet are not especially conducive to water above the planet’s surface.
From Universe Today:
But there’s a problem with Mars’ atmosphere – it is not thick enough now for water to be retained on Mars’ surface, and there is no scientific consensus that it was ever thick enough in the past to have allowed water to remain on the surface.
According to NASA, the study, which is published in the current issue of the journal Nature, backs up a hypothesis that warm water was present only on the planet’s surface for geologically short periods of time.
But don’t worry — this doesn’t rule out the possibility of life on the red planet.