Constraints on water activity at the Zhurong landing site in Utopia Planitia, Mars

Yong, ChengZheng; Fang, ZiYao; Zhang, CongCong; Jiang, Zhen; Qin, Liping

doi:10.26464/epp2023036

Cited by 2 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In situ explorations by Mars rovers have provided more detailed information. Sulfates have been identified by rovers, such as Opportunity, Spirit, Curiosity, and Zhurong, and most of them have also detected coexisting iron oxides with sulfates, mainly hematite (Clark et al., 2005; Klingelhöfer et al., 2004; Morris et al., 2006; Vaniman et al., 2014; Wang et al., 2006, 2023; Yong et al., 2023). A typical coexistence of sulfates and iron oxides was found by Opportunity at Meridiani Planum.…”

Section: Introductionmentioning

confidence: 99%

Brine Pools With Round Caps in the Western Qaidam Basin: Application to Iron Mobility and the Evaporation Formation of the Iron Oxide and Sulfate Assemblage on Mars

Fang,

Li,

et al. 2024

JGR Planets

Self Cite

View full text Add to dashboard Cite

The coexistence of sulfates and iron oxides is widespread on Mars, including at Meridiani Planum, the Opportunity rover's landing site. However, the formation mechanism is still poorly understood. Here, we report evaporitic iron oxyhydroxides and gypsum deposited as round caps in the center of brine pools in a playa area of the western Qaidam Basin in the northern Tibetan Plateau. Geochemical and mineralogical analyses indicate that the gypsum is precipitated in situ by strong evaporation of subsurface percolating brine containing dissolved iron. We suggest that the transport of iron from the anoxic subsurface and the evaporation of upwelling groundwater in an oxidized and hyperarid environment may have led to the co‐deposition of sulfates and iron oxides at Meridiani Planum and other similar sites on Mars. Our results also suggest that the subsurface water cycle could be an important source of iron mobility even under an oxidizing atmosphere and cold climatic conditions on Mars. Groundwater evaporation during the desiccation of Mars after the late Noachian may have contributed to the heterogeneous distribution of iron and the widespread coexistence of sulfates and iron oxides on the martian surface.

show abstract

Section: Introductionmentioning

confidence: 99%

Brine Pools With Round Caps in the Western Qaidam Basin: Application to Iron Mobility and the Evaporation Formation of the Iron Oxide and Sulfate Assemblage on Mars

Fang,

Li,

et al. 2024

JGR Planets

Self Cite

View full text Add to dashboard Cite

show abstract

Preservation of Microorganisms (Chroococcidiopsis sp. 029) in Salt Minerals under Low Atmospheric Pressure: Application to Life Detection on Mars

Fang,

Knoll,

McMahon

et al. 2024

Planet. Sci. J.

View full text Add to dashboard Cite

Salt minerals on Mars represent a promising target for investigating potential past surface and subsurface life. Terrestrial salt minerals have been shown to incorporate microorganisms within crystals. However, the effect of Mars’s low atmospheric pressure on the preservation of microorganisms in salt minerals during their formation remains unclear. Here we investigated the interactions between microorganisms (Chroococcidiopsis sp. 029) and crystals of halite (NaCl), epsomite (MgSO4·7H2O), and gypsum (CaSO4·2H2O) during the rapid evaporation of brines under simulated Martian atmospheric pressure. Parallel experiments were conducted under terrestrial pressure for comparison. Halite, epsomite, and gypsum formed under both terrestrial and low-pressure conditions, though crystal morphologies varied depending on the pressure. Microorganisms were identified within fluid inclusions or as solid inclusions in the crystal matrix. Halite crystals exhibited a greater propensity to incorporate cells under low pressure compared to terrestrial pressure, while the entrapment of cells in epsomite was similar under both conditions. In contrast, significantly fewer cells were trapped in gypsum crystals under low pressure. The results demonstrate the feasibility of cell entrapment in salt minerals formed by rapid evaporation under low-pressure conditions on Mars, and atmospheric pressure exerts distinct influences on different types of salts. The variation in fluid inclusion size in halite under different pressures even shows promise as a possible paleobarometer. Our findings suggest that halite is the most promising candidate for preserving potential Martian life and could be an excellent target for future Mars sample return missions.

show abstract

Constraints on water activity at the Zhurong landing site in Utopia Planitia, Mars

Cited by 2 publications

References 0 publications

Brine Pools With Round Caps in the Western Qaidam Basin: Application to Iron Mobility and the Evaporation Formation of the Iron Oxide and Sulfate Assemblage on Mars

Brine Pools With Round Caps in the Western Qaidam Basin: Application to Iron Mobility and the Evaporation Formation of the Iron Oxide and Sulfate Assemblage on Mars

Preservation of Microorganisms (Chroococcidiopsis sp. 029) in Salt Minerals under Low Atmospheric Pressure: Application to Life Detection on Mars

Contact Info

Product

Resources

About