Planetary atmosphere observation analysis

Abstract:

Heterogeneous electrochemistry induced by Martian dust activity is an important type of atmosphere-surface interaction that affects geochemical processes at the Martian surface and in the Martian atmosphere. We have experimentally demonstrated that heterogeneous electrochemistry stimulated by mid-strength dust events can decompose common chloride salts, which is accompanied by the release of chlorine atoms into the atmosphere and the generation of (per)chlorates (chlorates and perchlorates) and carbonates. In this study, we present quantitative analyses on the above products from 26 heterogeneous electrochemical experiments on chloride salts. Based on these quantifications, our calculation indicates that such atmosphere-surface interaction during a portion of Amazonian period could accumulate the observed abundance of (per)chlorates, carbonates, and HCl by landed and orbital missions, and thus can be considered as a major driving force of the global chlorine-cycle on Mars. This study emphasizes the importance of measuring the electrical properties of dust activity on Mars.

Abstract:

The study of isotopic ratios in planetary atmospheres gives an insight into the formation history and evolution of these objects. The more we can constrain these ratios, the better we can understand the history and future of our solar system. To help in this endeavour, we used Infrared Space Observatory Short Wavelength Spectrometer (ISO/SWS) Jupiter observations in the 793–1500 cm (Formula presented.) region together with the Nonlinear Optimal Estimator for MultivariatE Spectral analySIS (NEMESIS) radiative transfer suite to retrieve the temperature–pressure profile and the chemical abundances for various chemical species. We also used the 1500–2499 cm (Formula presented.) region to determine the cloud and aerosol structure of the upper troposphere. We obtained a best-fit simulated spectrum with (Formula presented.) for the 793–1500 cm (Formula presented.) region and (Formula presented.) for the 1500–2499 cm (Formula presented.) region. From the retrieved methane abundances, we obtained, within a 1 (Formula presented.) uncertainty, a (Formula presented.) C/ (Formula presented.) C ratio of 84 ± 27 and a D/H ratio of (3.5 ± 0.6) × 10 (Formula presented.), and these ratios are consistent with other published results from the literature.