Two new studies join the debate on whether or not there is liquid water on Mars

Two new independent studies join the raging debate over whether or not there really is sub-pole liquid water on the Red Planet. One of them is totally against it, however the other chooses to confirm that it does exist.

Recent studies reported the discovery of liquid water lakes under the polar ice caps of Mars, but others later refuted this major finding. With both positions at stake, many researchers begin to position themselves on one side or the other of the balance, each one with arguments and tests carried out independently.

All this part of 2018, when scientists analyzing radar data aboard ESA’s Mars Express orbiter reported some strange signals coming from near the Red Planet’s south pole. this signal indicated that there was a lake of liquid water about 20 km wide, located about 1.5 km below the ice cap.

In 2020, scientists studied a larger section of data and found signatures from three more subsurfaces.

However, and despite the fact that it seemed that the mystery was finally resolved, several studies published last year refuted the lake hypothesis. One of them found that these radar reflections were common in the region, even at depths too shallow for liquid water to exist.

The second found that deposits of clay, metallic minerals, and salt ice could create similar signals. And the third tested the clay hypothesis in the lab, checking radar reflections from frozen clay samples and finding that they matched signals from Mars Express.

With all this at stake, the matter was getting complicated and the investigations became polarized.

Now, Two new studies have joined the debate. The first, in favor, examined the salts that are believed to prevent water from freezing, and studied how they respond to radar. The team created brines and placed them in a chamber that mimics the pressure and temperature of the Martian environment.

As a conclusion, they found that these brines produce the same radar signal that the orbiter observed. This study was published in the revista Earth and Planetary Sciences Letters.

In the second study, by contrast, they added a global ice sheet to a model they designed and saw how it affected signals from different regions. The researchers discovered that many of the locations of these new bright spots corresponded to volcanic plains.

Rocks produced by iron-rich lava flows can reflect radar similarly on Earth, so that could be what’s happening on Mars as well. All these data and conclusions were published in the revista Geophysical Research Letters.

The liquid water lakes on Mars continue to give something to talk about and a single answer has not yet been reached. More and more studies seem to support alternative theories, which are usually simpler. But of course, More data will be needed to find out what is really going on under the Red Planet’s ice caps..