Ultraviolet Radiation Induced Desorption of Water from Martian Soil
نویسندگان
چکیده
The composition and pressure of the martian atmosphere allows solar ultraviolet photons as short as 190 nm to penetrate to the surface. The effects of UV photons on the hydration state of minerals has been investigated in the past with mixed results. Andersen and Huguenin [1977] proposed that photons with wavelengths shorter than 280 nm release water from goethite by ejecting OHgroups which subsequently combine with H+ from nearby lattice sites. However, Morris and Lauer [1981] repeated the experiments and found no UV dehydration effects on goethite or lepidocrocite in exposures equivalent to 10 to 100 years on the martian surface.
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