Highlights from Imaging Ultraviolet Spectroscopy of the Mars Atmosphere with MAVEN/IUVS
Résumé
The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission's Imaging Ultraviolet Spectrograph (IUVS) observes Mars in the far and mid ultraviolet (110-340 nm), investigating lower and upper atmospheric structure and indirectly probing neutral atmospheric escape. The instrument is among the most powerful spectrographs sent to another planet, with several key capabilities: separate Far-UV & Mid-UV channels for stray light control; a high-resolution echelle mode to resolve deuterium and hydrogen emission; internal instrument pointing and scanning capabilities to allow complete mapping and nearly continuous operation; and optimization for airglow studies. After two Earth years in orbit (one Mars year), IUVS has assembled a large quantity of data and provided insights on present-day processes at Mars including dayglow, nightglow, aurora, meteor showers, clouds, and solar-planetary interactions. In this presentation, we will highlight key results obtained by IUVS, including: (1) mapping of thermospheric composition, structure, and variability; (2) long-term tracking of H escape, O escape, and D/H ratios, and (3) detection and mapping of diffuse auroral emission. We will present an overview of these results and a discussion of their implications for understanding Mars atmospheric dynamics and evolution.