Liquid water still present on Mars
The confirmation fell in July: there is still water under the surface of the planet next to the Earth. This is the first evidence of the existence of a large body of water on Mars. The discovery of a frozen lake on its surface was announced in December.
The underground extension
We already knew that oceans once covered the Red Planet and that streams of brine sometimes still flow to a few places on its surface during the warmer months.
But what the Marsis radar instrument embarked on board the European Mars Express orbiter has detected is certainly one of the most important discoveries of recent years in astronomy.
The South Pole of Mars.
The liquid water is under the ice (in white) at the South Pole of Mars Photo: ESA / DLR / FU BERLIN / CC BY-SA There is therefore a vast underground lake 1.5 km deep under the ice cap of the South Pole. The stretch of water is about 20 km wide. Its temperature is probably below the freezing point of pure water, but the lake remains in the liquid state due to the presence of magnesium, calcium and sodium.
A lake on its surface
In addition, at the end of the year, a huge lake of frozen water was constantly observed by the European probe Mars Express in Korolev crater, nearly 82 kilometers wide.
The body of water is in the lowlands of the northern hemisphere of the planet.
In the center of this crater, the ice would have a thickness of nearly 2 kilometers.
The presence of liquid water is a prerequisite for the development of life. These two discoveries will not fail to intensify the search for other sources of water on Mars.