China’s Zhurong Mars rover revealed evidence of a 400,000-year-old temperature transition in Utopia Planitia, exhibiting dark ridges on top of brilliant dunes. Scientists were able to investigate enormous sand dunes near the rover’s landing in May 2021 because to the rover’s equipment and high-resolution pictures from China’s Tianwen-1 Mars orbiter. Over hundreds of thousands of years, the dunes’ crescent shape has been degraded, with long black ridges termed transverse aeolian ridges (TARs) growing on top of the dune fields at a different angle than the wind-blown dunes. TARs have been discovered in the lower mid-latitudes of Mars, but global atmospheric circulation models have been unable to explain how these structures developed. Between 2.1 million and 400,000 years ago, dark TARs emerged.
Milankovitch cycles created variations in the angle at which Mars spins, which caused the ice age to begin and terminate. These cycles, which correlate to climate variations, occurred on both Earth and Mars. Mars’ obliquity is now roughly 25 degrees.
