I saw this announcement last night on Scientific American – Water on Mars: Discovery of Three Buried Lakes Intrigues Scientists: https://www.scientificamerican.com/article/water-on-mars-discovery-of-three-buried-lakes-intrigues-scientists/. Worth a read if you are into things space-related.
Researchers say they have detected a group of lakes hidden under the Red Planet’s icy surface
The discovery, reported on 28 September in Nature Astronomy, was made using radar data from the European Space Agency’s (ESA) orbiting Mars Express spacecraft. It follows the detection of a single subsurface lake in the same region in 2018—which, if confirmed, would be the first body of liquid water ever detected on the red planet and a possible habitat for life. But that finding was based on just 29 observations made from 2012 to 2015, and many researchers said they needed more evidence to support the claim. The latest study used a broader data set comprising 134 observations from between 2012 and 2019.
“We identified the same body of water, but we also found three other bodies of water around the main one,” says planetary scientist Elena Pettinelli at the University of Rome, who is one of the paper’s co-authors. “It’s a complex system.”
The presence of the Martian lakes themselves is also still debated. After the 2018 discovery, researchers raised concerns such as the lack of an adequate heat source to turn the ice into water. And although the latest finding supports the 2018 observation and involves much more data, not everyone is yet convinced that the regions identified are liquid water.
“If the bright material really is liquid water, I think it’s more likely to represent some sort of slush or sludge,” says Mike Sori, a planetary geophysicist at from Purdue University, in West Lafayette, Indiana.
Jack Holt, a planetarty scientist at the University of Arizonasays that while he thinks the latest data are fine, he isn’t sure about the interpretation. “I do not think there are lakes,” says Holt, who is on the science team for the Mars Shallow Radar sounder (SHARAD) on NASA’s Mars Reconnaissance Orbiter (MRO). “There is not enough heat flow to support a brine here, even under the ice cap.”