China’s Zhurong Mars rover has made a significant discovery, revealing evidence of a striking climate shift on Mars approximately 400,000 years ago.
The rover, currently exploring Utopia Planitia, identified dark ridges atop bright dunes, shedding light on the planet’s climatic history.
Zhurong Rover’s Discovery Reveals
Led by Li Chunlai from the National Astronomical Observatories of the Chinese Academy of Sciences, a team of scientists utilized Zhurong’s instruments and high-resolution observations from China’s Tianwen-1 Mars orbiter to investigate the large sand dunes near the rover’s landing site in May 2021.
Over hundreds of thousands of years, the crescent-shaped dunes underwent erosion, resulting in the formation of transverse aeolian ridges (TARs) atop the dune fields.
Interestingly, the TARs displayed a distinct angle different from the wind-blown dunes.
While TARs have been observed across Mars at lower mid-latitudes, their formation remained unexplained by global atmospheric circulation models—until now.
Zhurong’s examination of the dunes revealed that the bright material forming the crescent-shaped bodies lay beneath the darker material constituting the TARs. Tianwen-1, from its orbit, identified 2,262 bright dunes scattered across Mars.
Read more: SpaceX Expands Starlink Constellation With Successful Launch Of 48 Satellites From California
Mars’ Climate Shifts and Ancient History
Based on the number of craters impacting the dunes, the research team estimated their formation to have occurred between 2.1 million and 400,000 years ago. Consequently, the dark TARs must have developed within the past 400,000 years.
These timeframes align with the commencement and conclusion of Mars’ previous major ice age.
The TARs’ distinct angle of formation suggests a shift in wind direction in the lower mid-latitudes, coinciding with the end of the ice age.
The ice age cycles on Mars, akin to those on Earth, result from changes in the planet’s obliquity—the angle at which it spins relative to the plane of its orbit.
The obliquity of Mars varied between 15 degrees and 35 degrees from 2.1 million to 400,000 years ago, causing significant climatic fluctuations. Currently, Mars’ obliquity stands at approximately 25 degrees.
The present geological era on Mars, known as the Amazonian epoch, spans between 3.55 and 1.88 billion years.
Understanding the climate during this period is crucial for comprehending the current Martian landscape, reservoirs of volatile matter, atmospheric conditions, and their correlation with models of ancient Martian climate.
Read more: Water Safety Alert: Study Shows Forever Chemicals In US Tap Water
