They detect signs of beaches of an old ocean on the red planet

Washington. The ground penetration radar data obtained by the rover chino Zhurong They revealed under the Martian surface indications of what seem sandy beaches of the coast of a large ocean that could have existed a long time ago in the northern plains of Mars.

The findings are the last tests that indicate the existence of this hypothetical ocean, called Deuteronilus, approximately between 3,500 and 4 billion years ago, a time when Mars – now cold and desolate – had a dense more atmosphere and a warmer climate.

According to scientists, a liquid water ocean on the Martian surface could have housed living organisms, as well as the original seas of the Earth.

He roverwhich worked between May 2021 and May 2022, toured approximately 1.9 kilometers in an area that has surface features that suggest the existence of an old coast. Its soil penetration radar, which transmits high frequency radio waves that are reflected in the subsoil, probe up to 80 meters below the surface.

Coastal deposits

Radar images detected underground layers of 10 to 35 meters of material thick with properties similar to the sand, all inclined in the same direction and with an angle similar to that of the Earth’s beaches, just below the water, where the sea ​​meets the earth.

The researchers mapped these structures in 1.2 kilometers during the trajectory of the rover.

The Martian surface has changed dramatically for 3,500 million years, but thanks to the ground penetration radar we have found direct evidence of coastal deposits that were not visible from the surfaceexplains Hai Liu, planetary scientist at the University of Canton and member of the Scientific Team of the Chinese Mission Tianwen-1, which included the rover.

On Earth, beach deposits of this size would have needed millions of years to form, according to the researchers, which suggests that on Mars there was a large and long -lived mass of water with an action of the waves that distributed the sediments dragged to it by the rivers that flow from the nearby highlands.

The beaches would have formed by processes similar to those of the Earth: Waves and tidessaid Liu, one of those responsible for the study published in the magazine Proceedings of the National Academy of Sciences. Such oceans would have deeply influenced the climate of Mars, molded their landscape and created potentially adequate environments for life to arise and prosper.

The coasts are ideal places to seek evidence of life in the pastindicated the planetary scientist and co -author of the study Michael Manga, from the University of California at Berkeley. It is believed that the earliest life on Earth began in places like this, near the air interface and shallow water.

He rover He explored in the southern part of Utopia Planitia, a great plain in the Northern Martian hemisphere.

A primary part of this work consisted of testing these other hypotheses. The dunes dragged by the wind were considered, but there were some problems. First, these tend to come in groups, which produce characteristic patterns that are not present in these depositsexplained the geo -scientific of Penn State and co -author of the study, Benjamín Cárdenas.

We also consider ancient rivers, which exist in some places near Mars, but we reject that hypothesis for similar reasons based on the patterns we saw in the deposits. And neither are structures like these in lava flows are usually found. Simply, the beaches are the ones that best fit the observationsCárdenas said.

The Earth, Mars and the other planets of the Solar System were formed about 4,500 million years ago. This means that Deuteronilus would have disappeared approximately one billion years ago, when the climate of the planet changed dramatically. According to scientists, part of the water could have lost in space, while large quantities could remain trapped underground.

A study published last year discovered that there could be an immense reserve of liquid water under the Martian surface, inside fractured igneous rocks.

For decades, scientists have used satellite images to draw traits of the Martian surface similar to a coast. But any evidence of this type on the surface could have been erased or distorted by billions of years of wind erosion or other geological processes.

It is not the case of newly discovered structures, which were buried over time under the material deposited by dust storms, meteorite impacts or volcanism.

They are very well preserved because they are still buried in the Martian subsoilCárdenas said.