Orbital and in situ observation of transverse aeolian ridges at Zhurong landing site

A large amount of transverse aeolian ridges (TARs) bedforms exist in the Zhurong rover landing region. The acquisition of high-resolution data from orbiter and the rover from Tianwen-1 mission provides an excellent opportunity to study the geological characteristics of TARs. The length, width, and density of a total of 8,274 TAR samples at the landing site are analyzed. The orientation of TARs at the landing region is dominated in an E-W direction. Analysis of Mars Climate Station (MCS) data shows that the present-day wind direction is inconsistent with the wind forces that promoted the formation of TARs, suggesting that the formation of TARs is dependent on the ancient wind direction.With the help of the Zhurong MarSCoDe shortwave infrared (SWIR) spectrometer data, we investigate the composition materials including TARs, soil, and rocks, and the results show that their spectra display similar distinct absorptions consistent with the presence of hydated minerals such as hydrated sulfates. The cemented and dusty crust covering the TARs indicate that the TARs have not migrated for a period of time in landing site area. Some of the TARs have been eroded into small sand ridges or ripples due to the change of the prevailing wind directions which may indicate the climate change on Mars.