Under the polo shirt on of the planet Mars exist salty liquid water lakes of various sizes, as described by an international team of scientists this Monday in the magazine Nature Astronomy.
The researchers believe that the wetlands they have detected in that Martian region are due to masses that remain in a liquid state, despite the low temperatures, thanks to a high concentration of perchlorate salts.
Previously, one of these regions under the surface of the red planet had already been identified based on data from one of the instruments on board the european shipMars Express, although the debate on its nature and composition had not yet been closed.
Roberto Orosei’s group, from the Roma III University, together with researchers from Australia and Germany, has now made use of the techniques used by the terrestrial satellites that track Antarctica in order to re-analyze the original data from the Mars Express radar, known as MARSIS. The device began collecting information on the planet in 2005, after being launched with the spacecraft in 2003.
After several years of acquiring data, the lack of clear evidence of liquid water under the Martian ice caps led scientists to believe that, if it existed, the liquid would be deeper than they had thought. In 2018, however, a reinterpretation of those explorations revealed a 20 kilometer wide lake in the region known as Ultimi Scopuli.
The work published this Monday, in which several of the authors of that original study participate, tries to shed new light on that discovery and expand its analysis. To do this, they have explored a region of 200 by 350 square kilometers around the location where the first lake was detected.
Their results “corroborate the initial discovery” of “a stable mass of liquid water in Ultimi Scopuli” using “a different technique than the independent one”, describes the text published in Nature Astronomy.
At the same time, his work has uncovered “a more extensive and complex scenario, with ubiquitous water patches around the subglacial lake“The physical, geological, climatic and topographic conditions that allow the existence of these liquid masses are still a matter of debate, the scientists emphasize.
At the same time, they stand out that hypersaline aqueous solutions have been found on Earth in subglacial areas at temperatures “much lower than the freezing point of water.”
Given these evidences, they propose that the most plausible form of liquid water under the Martian ice cap is the perchlorate brine, an aqueous solution with more than 5% salt concentration.