A surprising discovery in clay samples from Mars hints at the possibility that the planet may have been habitable for thousands of years and perhaps even as long as a million years. The clay was collected in Mars’ Gale Crater back in 2016 by NASA’s Curiosity Rover.
Since then, equipment on the rover has been taking X-rays of the clay samples and found that they contain a mineral called glauconite which is also found here on Earth (it is a green-colored iron potassium phyllosilicate). This is incredibly surprising and exciting as it could possibly mean that there was once life in the Gale Crater during a time in which scientists believe an ancient lake was once located approximately 3.5 billion years ago and that lasted as long as 10 million years.
The Gale Crater was created when a meteor slammed into Mars between 3.8 and 3.5 billion years ago. The large crater measures 96 miles in diameter (154 kilometers) and contains a mountain in the middle of it – this mountain is called “Mount Sharp” as a tribute to geologist Robert P. Sharp who passed away in 2004.
The discovery of glauconitic clays indicates that there may have been stable conditions on the Red Planet that could have supported life – specifically in the Gale Crater – which includes temperatures between -3 and +15 degrees Celsius (between 27 and 59 degrees Fahrenheit) as well as a neutral pH level in the water. Furthermore, these suitable conditions may have lasted as long as a million years.
Lead author Elisabeth Losa-Adams from the University of Vigo, Spain, explained, “Glauconitic clays can be used as ‘a proxy’ for stable conditions.” “The conditions under which these minerals form are friendly for the presence of life.”
She went on to say, “The existence of glauconitic clays indicates the presence of liquid water remaining long-term under steady-state conditions,” adding, “In addition, the geochemical parameters required for their formation (that is, neutral pH and low temperature) would have also created supportive habitable conditions for potential organisms.” The study was published in Nature Astronomy where it can be read in full.
It’s important to note that even though the discovery of glauconitic clays is very exciting news in regards to the possibility of Mars once containing some type of life, there still isn’t any solid proof that there is or ever was life on the Red Planet. We’ll have to wait and see what more information the rovers will discover while exploring the planet.