The Nature And Demographics of Small Exoplanets
One of the Kepler mission’s most significant discoveries is that planets smaller than Neptune are more common than larger ones in our galaxy. However, the host stars of Kepler planets are distant and faint. As a result, the vast majority of Kepler planets lack mass - and therefore density - measurements, so our knowledge of their interior structure and composition is very limited. I will present the small sample of known sub-Neptune exoplanets for which we do have mass measurements. I will discuss what we have learned about these systems until now, and how they inform our understanding of this population of exoplanets. I will conclude by describing how TESS, the next exoplanet hunter, will revolutionize this understanding by significantly increasing the number of known small exoplanets orbiting bright, nearby stars.