Exoplanet Exploration Program Analysis Group (ExoPAG) Study Analysis Group (SAG) 17 Final Report Resources Needed for Planetary Confirmation and Characterization

The upcoming TESS mission will detect thousands of candidate transiting exoplanets. Those candidates require extensive follow-up observations to distinguish genuine planets from false positives, and to resolve the physical properties of the planets and their host stars. While the TESS mission is funded to conduct those observations for the smallest and most Earth-size candidate systems, the large number of additional candidates will have to be vetted and measured by the rest of the astronomical community. To realize fully the scientific potential of the TESS mission, we must ensure that there are adequate observing resources for the community to examine the TESS transit candidates and find the best candidates for detailed characterization. The primary purpose of this report is to describe the follow-up observational needs for planetary discoveries made by transit surveys - in particular TESS. However, many of the same types of observations are necessary for the other discovery techniques as well, particularly with regards to the characterization of the host stars and the planetary orbits. It is worth acknowledging that while a planet discovery may be a one-time event, the deeper understanding of a planetary system is an ongoing process, requiring observations with better precision over longer time spans.