The French contribution to the EnVision mission (funded by CNES up to circa 30 M€) to the payload is spread over several instruments and/or experiments.
- Scientific responsibility and providing for the UV spectral imager VenSpec-U ;
- Providing for the optical subsystem of the IR imager VenSpec-M ;
- Scientific responsibility and pipeline development for the radioscience experiment.
The proposed spectrometers cover wavelength ranging from UV to infrared and will be used to detect temporal variations in surface temperature as well as in the concentration of volcanic gases in the atmosphere. These measurements will also make it possible to study interactions between the planet's surface and atmosphere. Radio science measurements will provide information on the vertical density of Venus’ atmosphere, the sulfuric acid content of the clouds (via radio occultations), as well as the internal structure of the planet through its gravity field (size and state of the core, mantle viscosity, crust and lithosphere structure).
These contributions are coordinated at the national level through a service national d'observation (SNO) during all phases, from their design and instrumental development (ongoing activities) to the development of the data processing pipeline and eventual archiving in the ESA's Planetary Science Archive.
