NASA: Perseverance moves in ancient lake of Mars (images)

The first scientific analysis of the images, sent from Mars by the robotic rover "Perseverance" (Perseverance) of NASA, confirms the initial assumptions of scientists that the jagged crater Jezero, in which it moves, was once a large lake, fed by delta of a river about 3,7 billion years ago.

Today, there is no liquid water on Mars, as the planet is very cold and the pressure in its sparse atmosphere is very low. It is estimated that Mars dried up about 2,5 billion years ago, probably when it lost its protective magnetic field and then its once dense atmosphere. But the new discovery is another indication that the neighboring planet was once hot and humid enough to have, like Earth, its own hydrological cycle, at least at times.

Also, images from Perseverance cameras, which are higher resolution and clearer than any other rover in the past, provide solid evidence that billions of years ago the 45-kilometer Jezero crater received - for some unknown reason - sudden floods, with water flow velocities of up to nine meters per second, which could move up to 3.000 cubic meters of water in one second. These floods were strong enough to move large rocks, one meter in diameter and weighing several tons, which were originally located tens of kilometers outside the crater, and eventually deposited them at the bottom of the lake, where they are now exposed.

Dozens of researchers, who published in the journal Science, estimate that the lake was calm for a long time, until a dramatic climate change for some unknown reason or a large meteor shower or intense volcanic activity triggered massive ice melting. and then violent floods. It is estimated that the lake that once existed in the current crater, had an area of ​​about 900 square kilometers.

"When you look at these pictures, you basically see an epic desert landscape. It is the loneliest place one could visit. There is no drop of water anywhere, yet we now have clues to a very different past. "Something very important has happened in the history of the planet," said MIT professor of planetary science Benjamin Wise, one of the scientists who analyzed the data.

As the car-sized rover explores the crater, which it reached on February 18, 2021 and has already traveled 2,6 kilometers, scientists hope to find out more about climate change on Mars. After all, having confirmed that the crater was once a lake, they are optimistic that in the sediments of its former seabed they will find traces of ancient aquatic life. That is why the rover will look for and collect samples of such sediments, which will be sent to Earth in the early 2030s for laboratory analysis and the discovery of possible Martian "bio-signatures".

"We now have the opportunity to look for fossils. It will take us some time until we have rocks in our hands in which we really hope to find traces of life. It is a marathon, but with many prospects, "said Tania Bozak, Associate Professor of Geobiology at MIT.

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