EnVision: Europe's Proposed Mission to Venus
The EnVision payload consists of 5 instruments provided by a consortium of European and American institutions that comprise a comprehensive measurement suite spanning infrared, ultraviolet-visible, microwave and VHF wavelengths. If selected, the proposed M-class mission will launch in 2032 on Ariane 62, arriving at Venus after a five month cruise, to perform 4 years of measurements with 5 cutting-edge instruments: an S-band Synthetic Aperture Radar (VenSAR), a Subsurface Radar Sounder (SRS) and VenSpec, a suite of three spectrometers and spectro-imagers: VenSpec-M (Infrared Imager), VenSpec-H (IR spectrometer), and VenSpec-U (UV spectrometer). Envision will also characterise the gravity field of Venus thanks to a Radio Science investigation exploiting the spacecraft TT&C system enhanced by the Ultra-stable Oscillator. Following orbit insertion and periapsis walk-down, orbit circularisation will be achieved by aerobraking over a period of several months, followed by a nominal science phase lasting at least 6 Venus days. EnVision will produce a huge dataset of geophysical data, so will permit investigation from across international planetary, exoplanetary and earth science disciplines. Lab-based and modelling work will also be required to interpret results from the mission.