Using new radar data from ESA’s Mars Express spacecraft, researchers have detected three reservoirs of liquid water trapped below the south polar cap of the Red Planet.
An artist’s impression of ESA’s Mars Express spacecraft. Image credit: ESA / ATG Medialab / DLR / FU Berlin / CC BY-SA 3.0 IGO.
In 2018, the Mars Express orbiter found evidence of liquid water under the ice in Ultimi Scopuli, a region near the south pole of Mars.
To establish the extent of subglacial water in this region, Dr. Elena Pettinelli from the Università degli studi Roma Tre and colleagues analyzed new data gathered by the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument onboard Mars Express.
“Mars was once warmer and wetter with water flowing across the surface, much like early Earth,” the researchers said.
“While it is not possible for water to remain stable on the surface today, the new result opens the possibility that an entire system of ancient lakes might exist underground, perhaps millions or even billions of years old.”
“They would be ideal locations to search for evidence of life on Mars, albeit very difficult to reach.”
Mars Orbiter Laser Altimeter topographic map of Ultimi Scopuli and location of MARSIS profiles collected in the region. Image credit: Lauro et al, doi: 10.1038/s41550-020-1200-6.
“Subglacial lakes are also known on Earth, like Lake Vostok in Antarctica,” they added.
“They harbor unique ecosystems, providing useful analogies for astrobiologists exploring how life can survive in extreme environments.”
Using techniques similar to those used in investigations of subglacial lakes in Antarctica, Canada and Greenland, Dr. Pettinelli and co-authors detected three new subglacial water bodies.
The largest reservoir measures about 20 x 30 km (12.4 x 18.6 miles), and is surrounded by several smaller bodies.
The water is thought to be very salty in order for it to remain liquid at cold temperatures.
“Our results strengthen the claim of the detection of a liquid water body at Ultimi Scopuli and indicate the presence of other wet areas nearby,” the scientists said.
“We suggest that the waters are hypersaline perchlorate brines, known to form at Martian polar regions and thought to survive for an extended period of time on a geological scale at below-eutectic temperatures.”
The study was published in the journal Nature Astronomy.
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S.E. Lauro et al. Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data. Nat Astron, published online September 28, 2020; doi: 10.1038/s41550-020-1200-6
