An ocean of water existed on Mars nearly 3.5 billion years ago, as per the latest finding. China’s Zhurong Mars rover has stumbled upon evidence of an ancient coastline on the red planet.
The findings were reported in the journal Scientific Reports. The rover found the coastline in the southern Utopia region which is a remnant of a sea that likely existed during the early history of Mars for a short period of time.
Scientists have long believed that as much as a third of the Red Planet was covered by an ocean billions of years ago.
The Zhurong rover has been studying the deposits in Vastitas Borealis, a low plain in the planet’s northern hemisphere after landing there in May 2021. This particular region is thought to have harboured an ocean once. The presence of fine grains of minerals like hydrated silica is likely a result of a coastline rather than volcanic activity.
Lead study author Bo Wu of The Hong Kong Polytechnic University told news agency AFP that several features in the area suggest that an ocean once lay around Zhurong’s landing area in the past. These features include “pitted cones, polygonal troughs and etched flows”.
As per previous research, crater-like pitted cones could have formed from mud volcanoes in areas where there had been water or ice.
Features hint at existence of ocean
Data gathered by the rover, as well as satellites, combined with analysis on Earth, also suggested that a shoreline was once near the area, according to the study.
The researchers believe that the ocean was formed by flooding nearly 3.7 billion years ago. Researchers analysed data from the Zhurong rover and the Mars Reconnaissance Orbiter to estimate surface ages and compositions of minerals found in the southern Utopia Planitia.
The existence of geological features like troughs and sediment channels in this part of the planet hints at an ancient nearshore zone. This is why researchers were forced to believe that the deposits were formed by a possible flooding event about 3.68 billion years ago.
“We conducted a comprehensive geomorphological analysis of the landing area using remote sensing data, supplemented by in situ observations, and unveiled features consistent with the existence of a nearshore zone in southern Utopia,” the researchers say.
However, scientists say that the rover’s data does not present direct evidence that an ancient ocean once existed on Mars.