Predicting and Finding Temperate Terrestrial Planets and Optimizing Their Future EPRV Observations

We’re likely missing ≳ 90% of the planets in the Solar Neighborhood, given that we expect each star to host at least one planet. Some of these hidden planets are temperate terrestrial planets with a potential to host extraterrestrial life. But how can we efficiently locate these planets and investigate them for biosignatures? Could they be hiding in already known systems? Here I investigated the orbital architectures and planetary characteristics of all nearby exoplanet systems and have determined which are most likely to host a temperate terrestrial planet. Using the DYNAMITE software package, I analyzed exoplanetary systems by combining the specific but incomplete observational data from a given system with population-level statistical models and dynamical constraints on system stability, and then predicted the orbital period, planet radius & mass, orbital inclination, and orbital eccentricity that one additional planet in each system would most likely have if it existed, along with the associated likelihood for each parameter. Along with the predicted planet parameters, DYNAMITE also provides the observable signatures produced by a planet with those characteristics for targeted follow-up observations. Upcoming high-precision radial velocity observations will monitor the 10 strongest candidate systems and search for the predicted planets. The RVs will also provide prioritized targets for planned EPRV characterization and the future NASA flagship mission searching for biosignatures, potentially bringing us significantly closer to finding life elsewhere in the universe.