EnVision is a proposed orbiter mission aiming at determining the level and nature of the geological activity and the sequence of events that generated the surface features of Venus, assessing whether Venus once had oceans (and was thus perhaps hospitable for life) and understanding the geodynamics framework that controls the release of internal heat over Venus’ history. EnVision will use a number of different techniques to search for active geological processes, measure changes in surface temperature associated with active volcanism, characterise regional and local geological features, determine crustal support mechanisms and constrain mantle and core properties.
The M-class mission would be launched on an Ariane 6.2 in 2032, 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 Experiment. The mission is currently in its concept study phase for a selection expected in 2021. EnVision would be an ESA mission, with a significant contribution and potential sharing of responsibilities with NASA currently under scientific, technical and programmatic assessment.
Venus exploration presents clear opportunities to address fundamental questions about the evolution of terrestrial planets and the appearance of life within our own solar system. Comparing the interior, surface and atmosphere evolution of Earth and Venus is essential to understanding what internal processes drove habitability of our own planet This is particularly true in an era where we expect hundreds, and then thousands, of Earth or Venus-sized exoplanets to be discovered.