Preparing for EMIRS: Using TES aerobraking observations to assess the diurnal variation of surface and atmospheric temperature.

Thermal infrared spectra taken by the Thermal Emission Spectrometer (TES) during its aerobraking phase are used here to characterize the diurnal variation of surface and atmospheric temperature. The TES aerobraking observations are one of the few available spacecraft datasets providing complete (or nearly complete) diurnal coverage over a range of latitudes and seasons. The diurnal variation of thermal contrast, or temperature difference between the surface and atmosphere, is a key quantity to consider for the retrieval of aerosol optical depth from thermal-IR spectra. We compare the observed thermal contrast as a function of season (Ls) and latitude to that predicted by the GCM results in the Mars Climate Database (MCD) to validate the model. This analysis will be used to guide development of retrieval algorithms for aerosol optical depth using observations from the Emirates Mars Infrared Spectrometer (EMIRS) thermal-IR spectrometer.

The Emirates Mars Mission (EMM) will launch in 2020 to explore the dynamics of the martian atmosphere on a global scale. The EMIRS instrument is an interferometric thermal infrared spectrometer developed by Arizona State University (ASU) and Mohammed Bin Rashid Space Centre (MBRSC). It builds on a long heritage of thermal infrared spectrometers designed, built, and managed by ASU's Mars Space Flight Facility, including the TES, Miniature Thermal Emission Spectrometer (Mini-TES), and the OSIRIS-REx Thermal Emission Spectrometer (OTES) instruments.