A new study published this week in the journal Nature Astronomy confirms the 2018 discovery, finding three new ponds in the vicinity. Researchers used radar data from the European Space Agency’s Mars Express spacecraft, studying a data set of 134 observations between 2012–2019.
To detect the lakes, a radar device from Mars Express sent radio waves to the surface of the red planet, which then reflected back in a certain way depending on the material there. A similar method is used to find subglacial lakes on Earth.
The high reflectivity found by the team of researchers suggests that there are large masses of liquid water trapped under the surface.
“The possibility of expanded hypersaline water bodies on Mars is particularly exciting because it has the potential for microorganisms to exist,” the team said. “Future missions to Mars should target the region to obtain experimental data regarding the basal hydrological system, its chemistry, and traces of astrobiological activity.”
The largest lake measured about 19 miles and is surrounded by several small ponds. Researchers believe the water to be salty, allowing it to remain liquid at Mars temperatures.
A very high salt content may mean that no life exists.
“These sparkling pools of Antarctica don’t have very active life,” John Priscu, an environmental scientist at Montana State University in Boisman, whose group studied microbiology in icy environments, told Nature. “They are just pickling. And that may be the case [on Mars]. ”
Scientists believe the findings point to the possibility of a much larger network of ancient underground lakes – which may be millions or billions of years old, when Mars was as hot and wet as Earth.
Water cannot currently remain stable on the surface of Mars due to the lack of sufficient atmosphere, but the presence of liquid water on Mars means that there is a 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 under a layer of ice.
“There can be a lot of water on Mars,” said study co-author Elena Patinelli, a planetary scientist at the University of Rome. “And if there was water, there was a possibility of life.”
But not everyone is convinced by the data. Mike Laurie, a planetary geophysicist at Purdue University in West Lafayette, Indiana, told Nature: “If the bright material is actually liquid water, I think it is more likely to represent some kind of slush or mud.”