SCMP reported that data from China's Zhurong Mars rover from the Tianwen-1 mission provided clues about the coastline of an ancient ocean that briefly existed on the surface of Mars about 3.5 billion years ago.
Data collected suggests that an ancient ocean may have left behind rocky sediments on the surface of Mars 3.5 billion years ago, according to a new study by scientists from the Hong Kong Polytechnic University (PolyU), China Academy of Space Technology and the Russian Academy of Sciences.
In 2021, the Zhurong rover began exploring the southern part of Utopia Planitia, a large plain in the northern hemisphere of Mars - which is thought to be part of an ancient ocean that once covered the red planet's northern lowlands.
Scientists discovered that the southern Utopia Planitia is divided into three parts of different depths, including a shallow sea part and a deep sea part, reinforcing the theory that the area was once covered by sea.
The discovery of sedimentary rocks and layering in rocks and sediments is also a sign of “past water activity,” scientists said in a paper published in the journal Scientific Reports on November 1.
Lead author Wu Bo, professor of space science and director of the Planetary Remote Sensing Laboratory at PolyU, said his team was the first to come up with a scenario that could explain how oceans formed.
Based on analysis of sensor data and observations from the Zhurong rover, the team estimates that the flooding of Utopia Planitia occurred approximately 3.68 billion years ago.
After a short-lived ice age formed the coastline, the ocean surface may have frozen over and disappeared around 3.42 billion years ago, Wu explained.
NASA's Viking 2 mission landed in the Utopia Planitia region in 1976 and mapped its surface.
For decades, scientists have studied the possibility of an ocean in the northern lowlands of Mars — a hypothesis that could reveal secrets about the early evolution of the red planet and how water affected Mars' climate and atmosphere.
In the latest study, researchers identified features consistent with the nearshore region of an ancient ocean, including volcanic-like cone-shaped structures, polygonal channels, and streams on the Martian surface.
“Current studies indicate that the volcano-like structures in southern Utopia may originate from mud volcanoes, which are often formed in areas with low groundwater or ice content,” said Wu.
The team will try to examine how water-related features on Mars formed and estimate the depths of the seas, Wu said. Comparing shallow and deep areas will help verify the ocean model they propose.
