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Chinese rover helps find evidence of ancient Martian life

8/11/2024 6:19
        With the assistance of
        China's Zhurong rover, scientists have gathered fresh evidence
        that Mars was home to an ocean billions of years ago - a far cry
        from the dry and desolate world it is today.
        
        Scientists said on Thursday that data obtained by Zhurong,
        which landed in the northern lowlands of Mars in 2021, and by
        orbiting spacecraft indicated the presence of geological
        features indicative of an ancient coastline. The rover analyzed
        rock on the Martian surface in a location called Utopia
        Planitia, a large plain in the planet's northern hemisphere.
        
        The researchers said data from China's Tianwen-1 Orbiter,
        NASA's Mars Reconnaissance Orbiter and the robotic six-wheeled
        rover indicated the existence of a water ocean during a period
        when Mars might already have become cold and dry and lost much
        of its atmosphere.
        
        They described surface features such as troughs, sediment
        channels and mud volcano formations indicative of a coastline,
        with evidence of both shallow and deeper marine environments.
        
        "We estimate the flooding of the Utopia Planitia on Mars was
        approximately 3.68 billion years ago. The ocean surface was
        likely frozen in a geologically short period," said Hong Kong
        Polytechnic University planetary scientist Bo Wu, lead author of
        the study published in the journal Scientific Reports.
        
        The ocean appears to have disappeared by approximately 3.42
        billion years ago, the researchers said.
        
        "The water was heavily silted, forming the layering
        structure of the deposits," Hong Kong Polytechnic University
        planetary scientist and study co-author Sergey Krasilnikov
        added.
        
        Like Earth and our solar system's other planets, Mars formed
        about 4.5 billion years ago. At the time the ocean apparently
        existed, it might already have begun its transition away from
        being a hospitable planet.
        
        "The presence of an ancient ocean on Mars has been proposed
        and studied for several decades, yet significant uncertainty
        remains," Wu said. "These findings not only provide further
        evidence to support the theory of a Martian ocean but also
        present, for the first time, a discussion on its probable
        evolutionary scenario."
        
        Water is seen as a key ingredient for life, and the past
        presence of an ocean raises the prospect that Mars at least at
        one time was capable of harboring microbial life.
        
        "At the beginning of Mars' history, when it probably had a
        thick, warm atmosphere, microbial life was much more likely,"
        Krasilnikov said.
        
        The solar-powered Zhurong, named after a mythical Chinese
        god of fire, began its work using six scientific instruments on
        the Martian surface in May 2021 and went into hibernation in May
        2022, likely met with excessive accumulation of sand and dust,
        according to its mission designer. It exceeded its original
        mission time span of three months.
        
        Researchers have sought to better understand what happened
        to all the water that once was present on the Martian surface.
        Another study, published in August and based on seismic data
        obtained by NASA's robotic InSight lander, indicated that an
        immense reservoir of liquid water may reside deep under the
        surface within fractured igneous rocks.
        



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