The radar installed aboard the European Space Agency's Mars Express orbiter provided evidence of the presence of a large lake at the south pole of Mars, hidden under ice. Thus, a long-term discussion about the presence of liquid water on the Red Planet was closed. This is stated in an article published in the journal Science.
According to the Italian scientist from the University of Bologna Roberto Orosei, even though the temperature in the reservoir is likely to be below the freezing point of water, the dissolved salts of magnesium, calcium and sodium, together with the pressure of the layer of ice lying above, allow the lake to remain liquid.
Note that for the first time, scientists started talking seriously about the presence of liquid water on Mars in the fall of 2015. Then experts noticed dark stripes up to five meters wide, which from time to time appeared on the steep Martian slopes. Nevertheless, all these years there was a debate about the physical nature of the spots.
In the new study, planetary scientists are relying on radar sensing. The MARSIS radar sends out radar pulses that penetrate the ice caps of Mars, after which it measures how the radio waves propagate and reflect. Analysis of this information helps specialists to recreate what is hidden from view.
From 2012 to December 2015, scientists led by Roberto Orosei used radar to survey the Planum Australe region, which lies within the ice cap at the south pole of Mars. As a result, the experts received 29 sets of radar "probes". Further exploration identified an unusual area 1.5 kilometers below the ice. In width, this territory stretched for 20 kilometers. The photograph of this site shocked scientists. The image is remarkably similar to the lakes found under glaciers in Antarctica and Greenland. This proves the presence of a lake with liquid water on the Red Planet.
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