The D/H Ratio in the Martian Upper Atmosphere
Résumé
MAVEN IUVS echelle channel measurements of the H and D Lyman-alpha emissions from the upper atmosphere of Mars have been carried out since late 2014. Following a determination of the global scale patterns in temperature and atomic number density, and the application of a new asymmetric radiative transfer code, it is now possible to quote accurate values for the densities of H and D and the D/H ratio in the martian upper atmosphere. The densities of both atoms show a strong seasonal variation with a large increase during southern summer /perihelion. At this same time the D/H ratio also increases strongly compared with aphelion, when it is close to the value in lower atmospheric water. Initial thoughts on the processes responsible for this variation will be presented.
Domaines
Planète et Univers [physics]Origine | Fichiers produits par l'(les) auteur(s) |
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