Chinese rover Zhurong finds evidence of ancient Martian shoreline

Scientists have uncovered new evidence suggesting that Mars once harboured an ocean, billions of years ago, with the help of China's Zhurong rover. This discovery, made through data from the rover and multiple spacecraft, provides fresh insights into the red planet’s ancient environment, revealing that it may have been far more habitable in the past than it is today.

The findings are based on data collected by Zhurong, which landed on Mars in 2021 as part of China's Tianwen-1 mission, Caliber.Az reports via foreign media.

The rover explored the Utopia Planitia region, a vast plain in the northern hemisphere, and discovered geological features that indicate the presence of an ancient shoreline. These features include troughs, sediment channels, and mud volcanoes—signs of past water activity—pointing to the existence of a large ocean.

In addition to Zhurong’s data, researchers also analyzed information from China’s Tianwen-1 orbiter and NASA’s Mars Reconnaissance Orbiter. The evidence gathered suggests that Mars once had a body of water during a period when the planet had already started to cool down, losing much of its atmosphere. This supports the theory that Mars may have been capable of sustaining liquid water at some point, even though the planet is now dry and inhospitable.

The researchers estimate that the flooding of Utopia Planitia occurred about 3.68 billion years ago, with the ocean likely freezing over in a short geological time frame. By approximately 3.42 billion years ago, the ocean had disappeared. According to the study’s co-author, Sergey Krasilnikov, the deposits left behind in the area show heavy silt, forming layered structures, further supporting the presence of an ancient marine environment.

The discovery of an ocean on Mars is significant because water is considered a key ingredient for life. This raises the possibility that microbial life could have existed on Mars when the planet had a warm, thick atmosphere and liquid water on its surface. "In Mars' early history, microbial life was much more likely," said Krasilnikov.

Zhurong, which was named after a mythical Chinese god of fire, operated on Mars for nearly a year, exceeding its original mission duration of three months. The rover’s mission ended in May 2022, when it went into hibernation due to a buildup of sand and dust. Despite this, the rover’s data has been invaluable in advancing our understanding of Mars’ past climate and its potential for supporting life.

This research adds to previous studies that have explored Mars' water history, including seismic data from NASA's InSight lander, which indicated the possibility of liquid water stored deep beneath the Martian surface. Together, these findings paint a picture of a once-habitable planet that may have been home to life.

By Vafa Guliyeva