Scientists have detected three new underground water reservoirs or lakes beneath the south pole of Mars. This is added to the first one discovered two years ago.

Four Underground Water Reservoirs

Now, a total of four of these underground water reservoirs could be below the Martian surface.

The researchers' new findings are published in the journal Nature Astronomy. The study is suggesting that there are more multiple liquid deposits on Mars than has been previously thought.

Nature World News - More Underground Martian Water Reservoirs Found
(Photo: NASA's Marshall Space Flight Center)
Crater Water Ice on Mars (ESA, Mars, 2005) / File photo

Past Discovery

An Italian research team studied the radar data of the Mars Express orbiter of the ESA or European Space Agency in 2018. With it, they found liquid water in the form of a lake situated one and a half kilometers below the planet's surface.

The water body was approximately 20 kilometers in length and is located at the base of Mars' South Polar Layered Deposits, a thick glacial area. The instrument used to detect the lake was MARSIS or Mars Advanced Radar for Sub-surface & Ionosphere Sounding.

READ: The Search for Life on Venus and Other Places in Our Solar System

The Discovery

After two years of completing the new analysis that the researchers made of MARSIS' more than 134 radar observations, they not only confirmed the lake's existence but found three more. None of them were farther than 50 kilometers relative to the first lake.

This latest analysis has a better discriminatory capacity to distinguish dry and wet sub-glacial features, which it learned from Greenland and Antarctica's radar data.

Lakes are Generally Similar

The four bodies of water appear to be very similar to one another. Their lengths are estimated to be within 10-30 kilometers, and all are roughly 1.5 kilometers beneath the ground. Their actual depths, however, are not yet known.

More Underground Martian Water Reservoirs Found
(Photo: Wikimedia Commons)
Scientists have detected three new underground water reservoirs or lakes beneath the south pole of Mars. This is added to the first one discovered two years ago.

The Water's Properties

The water in the lakes appears to be unsuitable for drinking. The scientists speculate that it can only maintain its liquid form in the freezing Martian landscape because it may be salty, as salts dramatically lower water's freezing point.

Salt deposits, including magnesium, calcium, and sodium, can be found all over the Red Planet, and past experiments show that they can be present in Mars' subpolar areas. Scientists speculate that brine may have stabilized the lakes in their liquid form for billions of years.

READ: Rainfall and Snowmelt From Storms May Have Filled Lakes, Rivers on Ancient Mars

Implications for Martian Colonists

The water is still an important discovery, even if it is not drinkable. Despite the possibility that it can be desalinated, it first has to be accessed by intense drilling. Meanwhile, the surface ice is plentiful enough and is much more accessible. 

The significance of the underground lakes is the possibility of them harboring Martian life. These microbial life forms may have evolved to be resistant to the sub-glacial salty lakes' extreme conditions and may be present there.

Roma Tre University physicist and study co-author Elena Pettinelli say that further studies may require a rover platform or lander after access to the lakes has been made. 

An alternative would be to use seismic measurements to determine the lakes' geometry and depth and determine which parts might be suitable for habitation. Nonetheless, the seismic measurements of these underground water reservoirs on Mars will not provide any definitive answers about life's presence on the Red Planet.

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Check out more news and information on Mars on Nature World News.