A team of Chinese scientists has found direct evidence for the existence of an ancient ocean in a plain in the northern region of Mars. This discovery was made through a detailed analysis of observations made by the Chinese rover Zhurong, which successfully landed in the Vastitas Borealis (VBF) geological unit in 2021, south of the Utopia Planitia plain. The study, published in the journal National Science Review, reveals sedimentary structures and features in the overlying rocks that indicate the presence of an ancient marine water body in the VBF.
The team of researchers, led by Xiao Long of the China University of Geosciences, suggests that the VBF was formed from large outflow channel flows, groundwater streams, and other river tributaries during the Hesperian period. This discovery demonstrates the existence of an ancient ocean on Mars and challenges previous theories based on remote analysis.
In the past, research had been conducted using remote sensing data in the northern lowlands of Mars, and in October last year, US scientists found evidence of a vast ocean that existed some 3.5 billion years ago on the surface of the red planet. However, the Chinese team argues that these earlier investigations were “controversial” due to the lack of direct geological analysis in the area.
This new discovery provides new clues to understanding the history of Mars and its past habitability. According to Xiao, further exploration and sampling of the region by the Zhurong rover is expected to deepen our understanding of the habitability of Mars and the preservation of possible traces of life on the planet.
The discovery of the ancient ocean on Mars by the Chinese team contributes to the growing body of knowledge about the red planet’s past and raises new questions about its potential to once harbor life.