From Berlin to Venus with VERITAS and EnVision — VNIR Emissivity Spectra of Venus Analogue Rocks and the VEM/VenSpec-M Verification Plan

Abstract

The Venus Emissivity Mapper (VEM) on the VERITAS mission and the VenSpec-M on the ESA EnVision mission are similar multi-spectral imaging systems designed specifically for mapping the surface of Venus using the near infrared atmospheric windows around 1 μm. They will provide the first global map of rock types on the surface of Venus as well as constant monitoring for volcanic activity at global (VERITAS) and regional/local (EnVision) scales. VEM/VenSpec-M will observe the surface of Venus in 14 bands: six bands are dedicated to mineralogy, two will be used to measure near-surface water vapor abundance, three will detect cloud contrast variations and three background bands will allow straylight correction. To correctly interpret VEM/VenSpec-M data and map the Venus surface composition, several types of data are needed: • emissivity laboratory data from samples at Venus surface temperatures • hemispherical reflectance data of Venus analogs • a proper VEM/VenSpec-M data verification plan that includes engineering instrument calibration and a careful data validation plan.