Science Goals and Mission Concept for a Landed Investigation of Mercury

Abstract Mercury holds valuable clues to the distribution of elements at birth solar system and how planets form evolve in close proximity their host stars. This Lander mission concept returns situ measurements that address fundamental science questions raised by MErcury Surface, Space ENvironment, GEochemistry, Ranging (MESSENGER) mission’s pioneering exploration Mercury. Such are needed understand Mercury's unique mineralogy geochemistry, characterize proportionally massive core's structure, measure planet's active ancient magnetic fields surface, investigate processes alter surface produce exosphere, provide ground truth for remote data sets. The achieves one full year (∼88 Earth days) operations with an 11-instrument, high-heritage payload delivered a landing site within widely distributed low-reflectance material, it addresses goals encompassing geophysics, space environment, geology. spacecraft launches 2035, four-stage flight uses electric propulsion cruise stage reach 2045. Landing is dusk meet thermal requirements, permitting ∼30 hr sunlight initial observations. radioisotope-powered lander continues through night. Direct-to-Earth communication possible 3 weeks landed operations, drops out 6 weeks, resumes final month. Thermal conditions exceed operating temperatures shortly after sunrise, ending operations. Approximately 11 GB returned Earth. cost estimate demonstrates feasible compelling as New Frontiers–class mission.