China’s Zhurong Rover has uncovered compelling evidence suggesting that Mars once had sandy beaches, further supporting the theory that an ancient ocean covered parts of the planet’s northern plains.
Scientists have long hypothesized that Mars was warmer and wetter around 3.5 to 4 billion years ago, with a vast ocean—dubbed Deuteronilus—stretching across its surface. The latest findings, published in Proceedings of the National Academy of Sciences (PNAS), reveal direct signs of coastal deposits beneath the planet’s surface.
Radar Confirms Ancient Shorelines
Using ground-penetrating radar, Zhurong detected sand-like layers buried 33 to 115 feet deep, all sloping in the same direction—a telltale sign of an ancient shoreline. According to Hai Liu, a planetary scientist at Guangzhou University, these deposits provide the first direct evidence of coastal features previously invisible from the surface.
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On Earth, sandy beaches form through millions of years of wave action, tides, and flowing rivers. If similar processes shaped Mars, this could mean its ocean lasted for millions of years, potentially creating an environment suitable for life.
A Prime Spot for Alien Life?
Shorelines are key locations for studying potential extinct life. Michael Manga, a planetary scientist at UC Berkeley, pointed out that Earth’s earliest life forms likely originated where air meets shallow water, making Martian beaches a promising target for future exploration.
While alternative explanations—such as wind-blown dunes or lava flows—were considered, the study’s co-author Benjamin Cardenas (Penn State) said none matched the patterns observed. “Beaches simply fit the observations the best,” he told Reuters.
Though Mars remains too distant for absolute confirmation, these findings add strong support to the theory that the Red Planet once had a vast ocean—and possibly life.
