Hydrated minerals discovered by the Chinese robotic probe on Mars in a vast basin believed to be the site of an ancient ocean suggest that water has been present on the planet’s surface longer than previously thought, Chinese scientists said.
According to an analysis of data sent back by the Zhurong rover, signs of water were detected in mineral samples from just 700 million years ago, the scientists said in a paper published Wednesday in the journal Science Advances.
Mars is believed to have been wet until about 3 billion years ago, when the planet’s second geological era, known as the Hesperian Epoch, ended. In the current Amazon period, there is no water on the surface.
The soil containing the minerals Zhurong collected had a hard crust that could have been formed by rising groundwater or melting ice that had since evaporated, the Chinese scientists wrote.
The Chinese probe has been exploring the vast Utopia Planitia plain since its landing on the planet in May last year. Zhurong traveled about 2 km from its landing site collecting terrain data.
In recent years, data from an orbiting probe operated by the European Space Agency has discovered water under the ice at the planet’s south pole.
Nearly all of Mars’ water is trapped in its polar ice caps, with very small traces in the planet’s thin atmosphere.
The location of groundwater is critical to determining the potential for life on the planet, as well as providing a permanent resource for any human exploration.
Translated by Luiz Roberto M. Gonçalves