Harmonic Analysis of the Martian Nitric Oxide Nightglow

Since 2014, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has continuously monitored the Nitric Oxide (NO) nightglow at Mars, thanks to the capabilities of the Imaging Ultraviolet Spectrograph (IUVS) instrument. The extensive spatial and temporal coverage acquired by IUVS allowed for the first detection of wave patterns in the NO nightglow. At the equatorial region, a wave-3 structure has been identified, as well as a wave-2 structure in the northern hemisphere for latitudes poleward of 60o. The interplay of these two wave components with latitude, local time, season, and altitude are not yet well understood.

We propose here to further the investigation of the wave-3 and wave-2 components discovered by IUVS by performing a comprehensive and systematic harmonic analysis that includes uncertainties for the components as allowed by the data. The information on the amplitude and phase of the observed waves obtained by such analysis will help to identify the waves’ origin and better define their characteristics. Furthermore, by providing information on the nightside of the planet in the 60-80 km altitude range, we will complete a gap in the current knowledge of non-migrating tides in the Martian atmosphere. To strengthen the interpretation of the MAVEN-IUVS data, we will incorporate and cross-correlate results from the Mars Reconnaissance Orbiter (MRO) Mars Climate Sounder (MCS) mesospheric temperature dataset as part of this study, as a harmonic analysis technique has already been successfully applied to this dataset and the MCS data covers similar altitude, latitude, longitude and solar local time ranges as the IUVS dataset. We will consider diurnal, semi-diurnal, non-migrating or migrating waves or a combination of them as origin of the observed patterns. The NO nightglow in the upper atmosphere of Mars acts as a tracer of the descending branch of sub-solar/anti-solar circulation. Thus, results from the NO nightglow behavior provided by our harmonic analysis will help place constrains on the atmospheric dynamics and transport to help improve outputs from Mars CGMs.

This project seeks to enhance the scientific return from missions to Mars as stated in the ROSE 2021 C.9 Mars Data Analysis document. This scientific investigation will seek to improve atmospheric models that further the understanding and forecasting of Mars atmospheric conditions.