Institute for Advanced Study Informal Astrophysics Seminar

No true extrasolar Earth analog is known. Hundreds of planets have been found around Sun-like stars that are either Earth-sized but on shorter periods, or else on year-long orbits but somewhat larger. Under strong assumptions, exoplanet catalogs have been used to make an extrapolated estimate of the rate at which Sun-like stars host Earth analogs. These studies are complicated by the fact that every catalog is censored by non-trivial selection effects and detection efficiencies, and every property (period, radius, etc.) is measured noisily. We have developed a general probabilistic framework for making justified inferences about the population of exoplanets (for example, the joint period and radius distribution), taking into account survey completeness and, for the first time, observational uncertainties. In this talk, I'll derive our method, describe how it can be generalized to other problems, and present the results applied to the Petigura et al. (2013) catalog of small planets orbiting Sun-like stars.