Improved algorithm for the transmittance estimation of spectra obtained with SOIR/Venus Express

Area of Science:

• Planetary Science
• Atmospheric Science
• Infrared Spectroscopy

Background:

• The Solar Occultation in the InfraRed (SOIR) instrument on ESA's Venus Express spacecraft collected data from Venus's atmosphere between 2006 and 2014.
• SOIR utilized solar occultations to study the mesosphere and lower thermosphere of Venus, gathering over 750 datasets.

Purpose of the Study:

• To develop and implement an improved procedure for estimating atmospheric transmittance from SOIR spectral data.
• To enhance the quality of calibrated spectra by reducing noise and improving solar normalization.

Main Methods:

• A novel transmittance estimation procedure was developed for infrared spectral data.
• The procedure focuses on minimizing rejected spectra and ensuring accurate calibration and normalization.
• The method was applied to solar occultation data from the Venus mesosphere and lower thermosphere.

Main Results:

• The new procedure successfully decreased the number of rejected spectra.
• It improved the calibration quality of the treated spectra.
• Noise reduction and accurate solar normalization led to higher quality calibrated spectra.

Conclusions:

• The developed transmittance estimation procedure significantly enhances the quality of SOIR data for Venus atmospheric analysis.
• This refined data processing allows for more reliable scientific interpretation of the Venusian mesosphere and lower thermosphere.
• The improved methodology contributes to a better understanding of Venus's atmospheric composition and dynamics.