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A comparison of 3‐D model predictions of Mars' oxygen corona with early MAVEN IUVS observations
Author(s) -
Lee Yuni,
Combi Michael R.,
Tenishev Valeriy,
Bougher Stephen W.,
Deighan Justin,
Schneider Nicholas M.,
McClintock William E.,
Jakosky Bruce M.
Publication year - 2015
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2015gl065291
Subject(s) - mars exploration program , thermosphere , atmosphere of mars , atmospheric escape , atmospheric sciences , brightness , altitude (triangle) , physics , atmospheric models , corona (planetary geology) , atmosphere (unit) , ionosphere , astrophysics , computational physics , environmental science , astrobiology , martian , astronomy , meteorology , venus , geometry , mathematics
We have compared our 3‐D hot O corona model predictions with the OI 130.4 nm emission detected by Imaging Ultraviolet Spectrograph/Mars Atmosphere and Volatile EvolutioN (IUVS/MAVEN) based completely on our best pre‐MAVEN understanding of the 3‐D structure of the thermosphere and ionosphere. The model was simulated appropriately for the observational conditions. In addition to dissociative recombination (DR) of O 2 + , DR of CO 2 + is also considered as an important hot O source. The model predictions showed excellent agreement with the transition altitude, the observed altitude variation of density, and the spatial variation of the corona with respect to the Mars‐Sun geometry. While previous models predicted escape rates covering a range of nearly 100, the brightness of the modeled hot O densities is a factor of ~1.5 lower than the observations. We discuss possible changes to the model that could come from further analysis of MAVEN measurements and that might close the gap between the modeled and observed brightness.