China’s Zhurong rover has discovered evidence beneath the Martian surface that suggests the presence of ancient sandy beaches, potentially linked to a vast ocean that may have covered parts of the planet billions of years ago, Reuters reported.
Using ground-penetrating radar, the rover identified layers of material buried 10 to 35 meters (33 to 115 feet) deep, resembling coastal deposits found on Earth.
These structures, spanning about 1.2 km (three-quarters of a mile), were tilted at an angle typical of underwater beach formations, supporting the theory that a large body of water once existed in Mars’ northern plains.
The ocean, known as Deuteronilus, is believed to have existed between 3.5 and 4 billion years ago when Mars had a thicker atmosphere and a warmer climate. Scientists suggest that such an environment could have supported microbial life, similar to early Earth’s primordial seas.
“The Martian surface has changed significantly over billions of years, but our radar data provides direct evidence of buried coastal deposits,” said planetary scientist Hai Liu of Guangzhou University, a researcher on China’s Tianwen-1 mission.
The study, published in Proceedings of the National Academy of Sciences, indicates that the ocean persisted long enough for wave action to shape the landscape, distributing sediments carried by rivers from nearby highlands.
Shorelines are prime locations for searching for ancient life, noted study co-author Michael Manga from the University of California, Berkeley. “Life on Earth is thought to have originated near shallow water-air interfaces like these,” he said.
The rover explored Utopia Planitia, a large Martian plain, ruling out alternative explanations for the formations. Researchers considered wind-blown dunes, river deposits, and lava flows but found that beach-like processes best matched the observed patterns.
Scientists believe Deuteronilus vanished as Mars underwent dramatic climate changes, with much of its water escaping into space or becoming trapped underground.
Recent research suggests that vast reservoirs of liquid water may still exist beneath the surface. The newly discovered formations, buried under layers of sediment, have remained remarkably well-preserved, offering fresh insight into Mars’ lost oceans.
