A hypothetical photograph of Mars 3.6 billion years ago, showing the Deuteronyl Ocean covering half the planet. (Photo courtesy of Robert Citron)
Based on ground-penetrating radar data obtained by the Chinese Mars rover, it can be assumed that Mars may have once been a popular resort, since sandy beaches stretched along the coast of a large ocean.
New data collected by the Zhurong rover during its exploration of the Red Planet provides the latest evidence that a vast ocean called Deuteronyl existed on Mars more than 3 billion years ago.
And, like the primordial seas of neighboring Earth, this ancient ocean could have become a habitat for life, scientists say. The team reported their findings Feb. 25 in the journal Proceedings of the National Academy of Sciences.
“We found areas on Mars that once looked like ancient beaches and river deltas,” said Benjamin Cardenas, an associate professor of geology at Penn State and a co-author of the study. “We found evidence of wind, waves, and a fair amount of sand — real resort beaches.”
The Zhurong rover landed on Mars in 2021 at Utopia Planitia, one of the oldest and largest impact basins on the Red Planet. Since then, it has been moving along the dry coastline, examining the surrounding geology for signs of evaporated water and ice.
Using radar to scan the planet's surface, Zhurong found layered structures filled with formations known as shoreline deposits. These deposits, like those on Earth's beaches, are typically formed from sediment carried by ocean tides and waves.
“This immediately caught our attention because it suggests waves, which means there was a dynamic interface between air and water,” Cardenas said. “When we think about where the earliest life evolved on Earth, we see that it was an interaction between oceans and land, and that creates an image of an ancient environment that was habitable, capable of supporting conditions favorable to microbial life.”
Additional comparisons with Earth's coastlines also helped scientists rule out other possible sources for these structures. Unlike formations created by old river flows, wind, or volcanic activity, the shape and structure of these depressions are much more consistent with a coastal origin.
“We see that the shoreline of this body of water changed over time,” Cardenas said. “We tend to think of Mars as a static image of the planet, but it was actually changing. Rivers flowed, sediments were moved, and land was formed and eroded. This type of sedimentary geology can tell us what the landscape looked like, how it evolved, and, importantly, help us determine where we should look for evidence of past life.”
If it did exist, Deuteronyl probably disappeared just a billion years into Mars' 4.5 billion-year history, but that would have been enough time for primitive life to have evolved. However, that fact alone is not enough to conclude that life ever existed on the planet.
However, definitive answers may be closer than we think. Samples of Martian dust and even evidence of ancient life may have already been collected by the Perseverance rover, which has been exploring Jezero Crater since 2021.
NASA originally planned to launch the search mission in 2026, but that date was pushed back to 2040 due to budget concerns. NASA is currently considering proposals from private companies to speed up the mission.
Sourse: www.livescience.com
