Two years ago, astronomersA huge lake beneath a thick layer of ice at the south pole of Mars. Now, scientists have confirmed that three new underground lakes have been discovered and detected in the same area – and they believe there may be many more.
A new study, published this week in the journal Nature Astronomy, confirms the 2018 discovery, which discovered three new lakes in the surrounding area. The researchers studied a data set of 134 observations between 2012-2019 using radar data from the European Space Agency’s Mars Express spacecraft.
To find the lakes, a radar instrument on the Mars Express sent radio waves to the surface of the red planet, which were accurately reflected back based on the material present there. A similar method is used to find subglacial lakes on Earth.
A team of researchers found that high reflectivity indicates that large amounts of liquid water are trapped beneath the surface.
“The prospect of expanded hypersalin water bodies on Mars is particularly exciting, as microbial life is likely to exist,” the team said. “Future missions to Mars should target this field to obtain experimental data in relation to the traces of the basal hydrologic system, its chemistry and astrobiological activity.”
The largest lake has found steps about 19 miles around and there are several smaller lakes around it. Researchers believe that the water there is salt, which remains liquid even at the cold temperatures of Mars.
Too high a salt content can mean that there is no life.
“These glossy bridges in Antarctica do not have a very active life,” said John Prescu, an environmental scientist at Bozman’s Montana State University, whose group studies microbiology in icy environments. “They’re just pickled. And that could be the case [on Mars]”
Scientists believe the findings show the potential for a large network of ancient underground lakes – which may be millions or even billions of years old, when Mars was as hot and humid as Earth.
Water on the surface of Mars cannot currently remain stagnant due to the lack of its significant atmosphere, but the presence of liquid water on Mars means the possibility of life. Subglacial lakes allow researchers to test how life can survive in extreme environments – but they are incredibly difficult to reach because they are buried a mile below the ice surface.
“There could be a lot of water on Mars,” said Elena Patinelli, a planetary scientist and study co-author at the University of Rome. “And if there was water, there is the possibility of life.”
But not everyone is convinced by the data. Mike Sori, a planetary geophysicist at Purdue University in West Lafayette, Indiana, told Nature: “If the luminous material is really liquid water, I think it represents some kind of slip or mud.”