Exciting discovery: 'Once upon a time there were beaches and coasts on Mars'

In the study, published in the journal Proceedings of the National Academy of Sciences, scientists made the discovery using ground-penetrating radar imaging of the northern plains of Mars. Co-author of the study, Dr. Benjamin Cardenas of Penn State University, said Zhurong was sent to this region, close to ancient coastlines previously mapped by satellite data.

Scientists explained that radar data showed the existence of sloping structures similar to the coasts on Earth, emphasizing that such structures are generally formed by the effects of tides, waves and rivers carrying sediment to the shore. “We see that this coast extends into the sea over time. It has grown at least 1.3 km northward,” said Cardenas, adding that they have found clues suggesting that water has been in motion on Mars for a long time.

The researchers stated that these sloping structures are not caused by volcanic movements, river beds or wind-borne sand dunes and can only be explained by the movement of a coastline. "Other geological processes frequently encountered on Mars do not explain this structure," said Cardenas, adding that the discovery offers important clues for research into whether there was past life on the planet.

"A coast is a transition zone between shallow water, air and land. It is in such environments that life is thought to have first emerged on Earth. So ancient coastlines on Mars could be an ideal place to search for traces of past life."

However, scientists also add that the beaches of Mars do not bear much resemblance to those on Earth. There were no palm trees or seagulls, and the beaches of Mars probably had a very cold climate.

"It would be amazing to see that," Cardenas said, adding that reconstructing ancient planetary surfaces is a work of imagination for geologists, and that the discovery has created great excitement in the scientific world.