Herschel/HIFI observations of Mars: First detection of O2 at submillimetre wavelengths and upper limits on HCl and H2O2 *
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چکیده
We report on an initial analysis of Herschel/HIFI observations of hydrogen chloride (HCl), hydrogen peroxide (H2O2), and molecular oxygen (O2) in the Martian atmosphere performed on 13 and 16 April 2010 (Ls ∼ 77◦). We derived a constant volume mixing ratio of 1400 ± 120 ppm for O2 and determined upper limits of 200 ppt for HCl and 2 ppb for H2O2. Radiative transfer model calculations indicate that the vertical profile of O2 may not be constant. Photochemical models determine the lowest values of H2O2 to be around Ls ∼ 75◦ but overestimate the volume mixing ratio compared to our measurements.
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تاریخ انتشار 2010