UV to IR spaceborne spectroscopic exploration of planets with European lead missions: achievements, results, future programs, and scientific goals

This article summarizes the formative achievements of European-led space missions for the exploration of the planetary system using UV to IR spectroscopic methods of remote sensing. It gives an overview of the different lines of development from a scientific, methodological, instrumental and programmatic point of view. These include imaging spectrometers for ESA missions in the UV/VIS to NIR/SWIR range such as Omega (Mars), VIRTIS (Comet 67P/ and Venus) and MAJIS (Jupiter and moons) with medium to high spectral resolution. With VIRTIS, a multi-channel combination with mapping and high spectral resolution capability has been developed and used for joint and simultaneous studies of surface and coma (Comet 67P/P) and atmospheric properties (Venus). With the ESA instrument MERTIS, imaging spectroscopy has been further developed for the MIR region in order to map the mineralogy of Mercury's surface globally. High spectral resolution instrument systems have been developed and deployed for ESA planetary missions to explore Mars and Venus and to study their atmospheres. These include PFS, SPICAM/MEX and SPICAV-SOIR/VEX. With the goal of a holistic understanding of planetary bodies, system packages of spectral sensors from the UV to the IR range are currently being developed that allow object-related, simultaneous and synergistic analysis of their environment, atmosphere and surface. An outstanding example of this development is the VenSpec system consisting of three spectral instruments currently being developed for ESA's M-type mission EnVision. This paper provides an outlook on future developments in UV to IR spectroscopy, with examples such as VenSpec, against the background of the scientific, instrumental and programmatic requirements for future ESA missions.