Does extra salty water, also known as brines, currently exist or ever existed on Mars, and why haven’t we found evidence of it? This is what a recent study published in the Proceedings of the National Academy of Sciences hopes to address as a pair of researchers discussed the plethora of reasons why we haven’t found evidence of brines on Mars. This study holds the potential to help researchers better understand why we haven’t found evidence of brines on Mars and whether liquid water ever existed on the Red Planet.
“I wanted to write this paper for a very long time,” said Dr. Vincent Chevrier, who is an associate research professor at the University of Arkansas and lead author of the study, “because I think there is a lot of confusion, a lot of misunderstanding, and a lot of erroneous interpretations of what the research papers are saying about the state of liquid water on Mars.”
For the study, the researchers discussed the observational history of identifying liquid water on Mars, the formation and stability of liquid brines under Martian conditions, and the past and present challenges of identifying liquid brines on Mars. In the end, the researchers concluded that the conditions on Mars give unlikely possibilities of liquid brines being stable on the surface. The researchers state many reasons for this, including the lack of salts identified on the surface, atmospheric pressure, and the location of ice, which could limit the amount of brines both above and beneath the surface.
The study states, “Despite these drawbacks and limitations, there is always the possibility that Martian life adapted to those brines and some terrestrial organisms could survive in them, which is a consideration for planetary protection because life on Mars might exist today in that case. Hence, detecting brines in situ remains a major objective of the exploration of the red planet.”
Evidence of surface brine remnants have been identified on the dwarf planet Ceres, giving clues that Ceres once, or currently, possesses a liquid water ocean beneath its surface. However, given the lack of evidence of surface brines existing on Mars, this could bring into question the history of liquid water ever existing on the Red Planet.
What new discoveries about brines on Mars will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Proceedings of the National Academy of Sciences, University of Arkansas, EurekAlert!
Featured Image: Artist’s rendition of liquid water existing in Gale Crater on Mars billions of years ago. (Credit: NASA/Evan Williams/Mars Reconnaissance Orbiter HIRISE project)
