Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging Plus (DAVINCI+): Discovering a New Venus via a Flyby, Probe, Orbiter Mission

NASA's next possible Venus mission concept within the Discovery Program is "DAVINCI+", a multi-spacecraft approach designed to resolve major scientific questions remaining about Venus, and Venus analogs beyond our solar system. The architecture, payload, and timeline of this ground-breaking mission will be discussed. DAVINCI+'s planned observations are intended to provide first-of-a-kind, definitive atmospheric chemistry measurements from the top of the clouds to the near-surface at a quality typical of landed in situ instruments such as those on the NASA/JPL Curiosity Rover. In addition, its descent imaging system will acquire over 100 high-sensitivity images in the near-IR atmospheric window from ~ 10 km to the surface, to ultimately provide sub-meter resolution imaging and 3D topographic data for a region of the complex-ridged terrain in Alpha Regio. Together with the deep atmosphere descent probe measurements acquired during a ~ 60 minute transit to the surface, the mission will conduct two remote-sensing Venus flybys with its UV, NIR imaging system to explore the upper atmosphere, as well as night-side IR emissivity. After the probe entry, descent, and touchdown, the carrier spacecraft will return to Venus and enter orbit for up to one Venus year of systematic dayside UV imaging together with night-side Near IR emissivity imaging of major highlands. These data will hopefully provide a foundation for all future missions to Venus, including planned radar orbiters by ESA (EnVision) and possible Lander-Balloon-orbiters by Russia and partners (Venera-D). DAVINCI+'s scientific outcomes directly address long-standing questions about Venus that have perplexed the community for decades, and which have been stumbling blocks as the evolution of Earth, Mars, and Venus have been contrasted. The history of water in Venus' history will be addressed via definitive measurements of D/H at multiple altitudes in the atmosphere, with links to the role of past oceans, if any. The chemical evolution of the massive Venus atmosphere will be investigated via critical noble gases including xenon, as well as by means of a suite of trace gas species every few 100 meters in the sub-cloud atmosphere and into the super-critical CO2 lower region. Near IR imaging will provide compositional constraints at spatial scales as small as ~30 m for regions of the tesserae, connecting local spatial scales to those that will also be explored at 50-100 km scales from flyby and orbit. Ultimately, DAVINCI+'s integrated flyby, orbital, and in situ probe-based suite of measurements will enable Venus-like exo-planets to be better understood, as a new era of exoplanet astrophysics emerges via TESS, JWST, WFIRST, and beyond.