Mars from 3.6 billion years ago had beaches, says study

Mars may have housed an ocean with waves They hit sandy beaches 3.6 billion years ago, according to a new survey. The Rover Zhurong of China and its soil penetration radar detected old coastal lines when he operated between May 2021 and May 2022.

The vehicle landed in Utopia Planitia, a plain within the largest impact basin known on the red planet, near a series of mountain ranges in the northern hemisphere of Mars.

Scientists had long questioned whether the mountain ranges could represent the remnants of a coastal line, so Zhurong set off in search of evidence of ancient water.

The study, based on data collected by Zhurong while its radar instrument examined the hidden rock layers under the surface, was published last Monday (24) in the magazine Proceedings of the National Academy of Sciences.

“We are finding places on Mars that used to look like old beaches and ancient rivers of rivers,” said study co -author Benjamin Cardinas, assistant professor of geology at the Penn State Department of Geosciences in a statement. “We find evidence of wind, waves, lots of sand – a suitable beach, a holiday style.”

In addition, it is possible that the Martian environment was warmer and damp by tens of millions of years beyond what was previously suspected, the authors of the study wrote. Revelations add to the evidence that the planet had an ocean that covered one third of the Martian surface-conditions that may have created an environment conducive to life.

The search for the old ocean of Mars

In the 1970s, NASA’s Mariner 9 and Viking 2 missions were the first to observe characteristics that suggested the presence of an ancient ocean on Mars. Planitia utopia dates from the Hesperian period, or from 3.7 billion to 3 billion years ago, and lacks abundant evidence of standing water, unlike the oldest regions on the planet, said Aaron Cavosie, planetary scientist and senior teacher at the Curtin University Center for Space and Space Technology in Perth, Australia. Cavosie did not participate in the new study.

“The Mariner 9 orbiter first recorded giant canyons on Mars Hesperian surfaces in the 1970s, but they are generally seen as representing catastrophic explosions of groundwater on the surface rather than evidence of standing water,” said Cavosie. “The idea is that the mood of Mars cooled at this time and the surface dried.”

Multiple spacecraft captured observations that suggest that much of the water has escaped to space as the planet’s atmosphere has disappeared – astronomers are still investigating what caused this dramatic transformation. As the planet cooled, part of the water probably moved to the underground in the form of ice or combined with rocks to create minerals.

Viking images showed what seemed to be a coastal line in the northern hemisphere. But in strong contrast with the leafled coastal lines on Earth, the Martian feature was irregularly cut, with high differences of up to 10 kilometers.

The co -author of the study Michael Manga, professor of Earth Sciences and Planetary at the University of California, Berkeley, and his colleagues previously suggested that volcanic activity in the region, as well as a change in Mars rotation, changed the coastal line and caused it to become irregular over time.

“As the red planet’s axis of rotation has changed, the shape too. And so, what used to be flat is no longer flat, ”said Manga.

But what scientists needed most to answer their questions were observations made with “soil boots,” or in this case Rover trails, Cavosie said. Zhurong would be able to see if the rock layers buried in planitia utopia were volcanic or contained sediments consistent with those of an ocean.

The dive of a coastal line

When Zhurong landed, he traveled along the mountain ranges, collecting data up to 80 meters below the surface with radar.

Between 10 and 35 meters deep, the Rover radar detected sedimentary structures similar to layered beaches on the earth that dived at an angle of 14.5 degrees. The radar also measured the size of the particles, which corresponded to that of grains of sand.

“The structures don’t look like sand dunes,” said Manga. “They don’t look like an impact crater. They do not look like lava flows. That’s when we started thinking about oceans. The guidance of these characteristics is parallel to what would have been the old coastal line. ”

The structures strongly resemble the coastal sedimentary accumulations on Earth, such as those found in Bengal Bay, formed by the presence of a long -term stable ocean, the study authors said. The team believes Rover found “coastal deposits”, which take millions of years to form as tidal and waves sediments lean toward an ocean.

“This caught our attention immediately because it suggests that there were waves, which means there was a dynamic interface between air and water,” said Cardinas. “When we look at where the oldest life on Earth developed, it was in the interaction between oceans and earth, so this is painting an old housing environments, capable of sheltering conditions favorable to microbial life.”

The rivers probably helped dump sediments in the oceans, which were then distributed by the waves to create beaches. Sedimentary rocks, carved channels and even the remains of an old river delta, studied by NASA’s Rover perseverance, showed how water once shaped the Martian landscape.

After the ocean dried, the beaches were probably covered by volcanic eruptions and dust storm material, effectively preserving the coastline, Cardenas said. “It’s always a challenge to know how the last 3.5 billion years of erosion on Mars may have altered or completely deleted evidence from an ocean,” he said. “But not with these deposits. This is a very unique data set. ”

Now the team wants to determine the height of the waves and tides inside the ocean, how long the ocean has persisted and a potentially habitable environment has been provided, Manga said.

François Forget, senior research scientist and research director at the French National Center for Scientific Research, said he is not fully convinced by the hypothesis presented in the study that only ocean coastal lines can explain radar data. Forget was not involved in the new research.

“I don’t think we can be sure that the observations could not be explained by dune processes,” or the formation of sand dunes, which Forget said he believed it was more likely on Mars.

Meanwhile, Dr. Joe McNeil, a planetary scientist and postdoctoral researcher at the London Natural History Museum, believes the findings add weight to the hypothesis of an ancient North Ocean in Mars by providing crucial evidence of the underground. Mcneil was not involved in the new study.

“If these coastal deposits actually represent the deposition of sediments on the edge of an old ocean, this suggests a prolonged period of stable liquid water, which has great implications for Mars’s climate history,” McNeil said. “This would mean that Mars had conditions that could have supported a hydrological system with environments potentially habitable by substantial amounts of time.”

See also

Water crystals found on Mars indicate life possibility

This content was originally published on Mars from 3.6 billion years ago had beaches, says study on CNN Brazil.

Source: CNN Brasil