Currently, Mars is characterized by its cold and arid conditions, yet this wasn't its perpetual state. Upon scrutinizing the high-frequency radar data collected by the Zhurong rover, scientists have uncovered that notable water activity persisted on the Martian surface approximately 750 million years in the past. This revelation extends the timeline of water existence on Mars by several hundred million years, offering fresh insights into our comprehension of the planet. Previously, the consensus within the scientific community held that Mars had transitioned to a predominantly dry state around 3 billion years ago.

The Zhurong rover's explorations in the southern reaches of the Utopia Planitia on Mars unveiled uniformly layered sedimentary deposits beneath the surface at its landing site, with impact craters lying underneath. These sedimentary features suggest a depositional environment influenced by water during that era. Moreover, the fine stratification captured by the radar further corroborates the presence of a shallow aquatic setting. By integrating the dating analysis of the impact craters, researchers have ascertained that the sedimentary layers date back 750 million years, signifying that persistent water activity continued on Mars during that specific timeframe.