Abstract

I will discuss recent modeling results from two different areas of exoplanet theory.  First, Lyman-alpha transits have long been used to probe the outflows from planets experiencing atmospheric evaporation.  Often, observed transits are interpreted in terms of mass loss rates, but these interpretations are generally model-dependent.  I will demonstrate that Lyman-alpha transits can more cleanly be used to constrain the outflow velocity of the escaping gas, a key property that can be used to distinguish whether photo-evaporation and core-powered mass loss models better describe observed outflows.  Second, I will discuss how accretion of ices by growing solids in the outer regions of protoplanetary disks may affect not only the compositions of planetesimals but also the global distribution of planet-forming material.