The China National Space Administration’s Tianwen-1 mission landed the Zhurong rover on the surface of Mars on May 14, 2021. The instrument suite on Zhurong includes a ground-penetrating radar, magnetometer, remote sensing spectrometer, multiple cameras, and a climate station. The landing site, Utopia Planitia, is possibly the largest impact basin in the northern lowlands of Mars. The aqueous history of this basin has been characterized using orbital imaging data before landing and includes features that indicate flooding, material infill, and a volatile-rich surface layer. The aqueous history of this region is important for understanding the climate and potential habitability of Mars and for understanding how it transitioned from a cold and wet environment in the past to the cold and dry climate that we see today.
Previously, orbital mapping identified the presence of, albeit sporadic, hydrous minerals at the Tianwen-1 landing site. The Zhurong rover performed in-situ measurements using its short-wave infrared spectrometer (SWIR) on the Mars Surface Compound Detector (MarSCoDe) instrument to search for such minerals. Yang Liu and colleagues from the State Key Laboratory of China present Navigation and Terrain Camera (NaTeCam) data that identified two distinct rock types based on these data: a dark-toned material and a brighter-toned material.
MarSCoDe targeted the brighter-toned material using SWIR and detected the possible presence of hydrated silicates and sulfates, such as gypsum, epsomite, or bassanite. These have been tentatively interpreted as duricrusts, which are layers of cemented regolith that form due to aqueous activity (i.e., the dissolution and precipitation of minerals). However, definitive mineral assignments could not be made due to low signal-to-noise and the absence of diagnostic spectral features. Continued exploration of the Utopia Planitia landing site by Zhurong will prove useful for mineralogical and contextual characterization, including a greater suite of spectroscopic measurements to improve the confidence of mineral identification. READ MORE